Pete's FD resto-mod project
 

I’ve had this FD for about 15 months now, so I figured it’s about time to get off my rump and do a build thread… Here’s some pictures from my pre-purchase inspection trip to SC, November 16, 2019, and then some more pictures taken on delivery day at my place in MD.

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Pre-purchase inspection trip, 11/16/19
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Pre-purchase inspection trip, 11/16/19
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Delivery day, 11/20/19, rolling off the transporter
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Delivery day, meeting the FC garage mate!
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Another on delivery day
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Engine bay shot

If you’re sensing some déjà vu from the pictures, it’s because the PO that I bought it from had a build thread on here too, here’s the link for the history buffs… https://www.rx7club.com/build-thread...build-1113634/

After spending lots of time hunting down a decent FD to use as a starting point for a resto-mod project, I stumbled on this one on FB. I wanted one with a clean & rust-free body, good paint, good interior, solid suspension & brakes. Mechanically, I was open to anything from OEM stock (i.e., twins) to a single turbo conversion (if it was done right). This one checked most of my boxes – key things being rust free clean body work with recent paint, relatively low mile chassis (< 68K miles when I got it), and the factor that sold me on it was the PO dropped a brand-new Mazda 13B-REW crate motor in it just before I did the pre-purchase inspection; I test drove it with less than 20 miles on the new motor. It was already modified, but for the most part the work was done right, and I can make use of most of the parts.

So here’s the specs and go-fast parts list as I got it:

Turblown S300 turbo kit; consisted of a Borg-Warner S364.5 SXE turbo with a 1.0 AR turbine housing; Turblown stainless tubular welded exhaust manifold with dual Turbosmart Comp 40 waste gates (40mm, 12Lb springs) & open dump tubes. The PO fabricated a V-banded 3” downpipe that mates up with a custom fabricated 3” exhaust system that he built. It’s 3” straight thru, except for a largish oval dual-tip muffler of unknown brand. Looks OEM, solid construction but it’s loud as hell and drones on the highway – plan to fix that with either a Racing Beat or Tanabe catback, a 3” resonated pre-silencer mid-pipe (probably RB), and some fab work to mate that stuff to the existing 3” DP.

On the air intake side, it had a large Apexi FMIC, a 90mm GM DBW throttle body, and a 13B-RE Cosmo UIM/LIM. On the fuel side, the FI’s are Bosch 1000cc extended tip EV14’s as primaries, and Bosch 2200cc secondaries. Plumbing is FFE fuel rails, Fuel Labs FPR, a Continental flex-fuel sensor, some hard line and SS braided with a Stabuli quick release/no leak coupling on the pressure side. Still running the OEM FD fuel pump though, so that’s on my upgrade short list.

Engine management is a Link G4+ Fury ECU. The PO did a nice job building a wiring harness for it, which included a mil-spec 55 pin circular firewall connector. Unfortunately, he didn’t wire in OMP support and a few other OEM integrations I’d like the Link to support, such as OEM-like 3 speed fan controls or wiring to support cruise control via the Link & DBW throttle. So I'll be doing a new wiring harness

On the interior, the plastics were in pretty decent shape all around, but tan. Easy enough to refinish using the SEM paints as described elsewhere on the forum. And since the PO was going for simple track beast when it was his build, there was no radio/speakers, so it had the pictured HVAC/radio panel that fits 6 gauges instead of a radio that I need to replace. The tan seat belts were also too filthy to get clean, and the webbing was looking worn. So besides adding an audio system and getting the belts re-webbed/restored, some interior restoration and possibly a full tan to black conversion is in the works.


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No radio, but plenty of space for gauges


Suspension & brakes were pretty solid – Tokico Illumina adjustable (5 way) shocks with Tein springs front & rear. Not sure what model/spec the springs are – the car sits at what looks to me like stock ride height, maybe a smidge lower. Front stabilizer bar looks aftermarket, from diameter and red color, I think it’s the RB bar. Rear bar is OEM, and as far as I or the PO know, all the bushings are original OEM. I thought the pillow ball bushings would be shot by now, but they all seem to be holding upon inspection and test drives. One problem I found is the OEM liquid filled diff bushings have leaked, so fixing that is on my to-do list. Brakes are basically stock, with some aftermarket drilled/slotted rotors, and the ABS pump was removed & bypassed with the Alex Rodriguez kit and Wildwood proportioning valve.

Wheels & tires are a staggered setup, with Enkei RPF-1s, 17 x 8-1/2” Front & 17 x 9-1/2” Rear, with a set of Firestone Firehawk Indy 500s, 245/45R-17 Front, 275/40R-17 Rear. As far as I can see, they don’t rub anywhere.

My plans for this FD are to make it more comfortable and stealthier for street use, but still be stupid fast and fun to drive on twisty roads and an occasional track day. Essentially an FD version of my FC resto-mod! Something that can get me to & from Deals Gap in reasonable comfort on the interstate, and keep a s**t eating grin on my face when I’m driving the snot out of it on the twisty roads down there.

Being an engineer and project manager by trade, I always have a structured plan for my car projects. Below were my goals for "Phase 1" of my FD project. Thanks to this damned COVID pandemic, I had plenty of extra time and got all my goals done. I’ll share more details in subsequent posts

The following were my goals for Phase 1:

1. Complete a full rewire of the Link G4+ Fury ECU to implement all the features I wanted (e.g., OMP support, Cruise Control via DBW, add in knock, oil pressure & oil temp sensors), and bring any unused I/O out to accessible connector(s) for future use.
2. Install an FD OMP (2x used FD OMPs were provided by the PO with the car), along with an RA OMP adapter kit and 2-stroke oil tank (i.e., premix oil delivery managed by the Link ECU). This replicates the setup I have on my FC – I love not having to mess with adding premix at every gas stop.
3. Add an Oil Pan Brace to prevent leaks.
4. While engine is removed for the Oil Pan Brace installation, verify end play of the E-shaft, and do the E-shaft thermal pellet oil mod.
5. Add new oil pressure & oil temperature sensors for the Link ECU, and a Banzai Racing oil filter pedestal to mount the sensors.
6. Upgrade the single oil cooler setup to the OEM RX7 R1/R2 dual oil cooler configuration.
7. Revise/replace the existing Apexi front mount intercooler and Megan racing radiator arrangement to enable restoration of a working A/C system – this will involve going to a larger SMIC, or a V-mount arrangement.
8. Undo the PO’s battery relocation mod, and move the battery back under the hood. The battery relocation wasn't up to my standards.
9. Get the filthy tan seat belts rebuilt & re-webbed, and refinish most of the plastic interior panels from tan to black and add some sound insulation to the doors, hatch area and under the storage bins to reduce NVH. Not sure yet if I'm doing a full or partial tan-to-black conversion - I may retain the tan seat color & carpeting.
10. Replace the missing front bumper reinforcement bar, and missing plastic front undertray parts that I discovered.
11. Start restoring the A/C system - the PO chucked all the under hood A/C components to make room for the turbo & FMIC. Fortunately all the HVAC wiring is in place and unmolested, as is the OEM Denso evaporator core under the dash, which was properly plugged to keep critters out of it.

But before I could do any of that stuff, I needed to sort out the tune on the Link ECU - it was running stupid rich and the DBW & idle tuning was a bit jacked up when I got it. Fortunately I did my homework researching the Link G4+ ECU, and found their software and tuning app to be very intuitive and easy to learn. So it didn't take me long to get the idle, NA mode/off boost AFRs where they needed to be and get the DBW settings right. While doing that I logged almost 500 break-in miles on the new motor, so with that done, I was ready to start tearing int the project.

Congrats Pete.
Looks like a very solid car now just make it your own.
Lots of good work going on!

Nice, congrats on the purchase and goals.

Very nice. I am excited to follow this. Looks like a good solid car to start with.

Thanks for the kind words guys!

On this post, I’ll cover the Link G4+ ECU rewire and electrical integration with the OEM wiring. I’ve had professional engineering experience with military spec wiring on Army combat vehicles & electronics, but this is the first time I built my own ECU harness to motorsports/”mil-spec” design standards. It was a great learning experience, and the end result came out really well. I found a lot of useful tips and pointers about motorsports wiring practices from this website here: https://www.rbracing-rsr.com/wiring_ecu.html

I don’t have many pictures to share, but below are a few shots of the harness while it was under construction. Concentric twist wiring is more of an art than a science, especially when you have to deal with multiple wire gauges and twisted/shielded pair wiring running within the same harness. These pictures were a few of the many iterations, until I found what worked. Planning is key; ideally, you’ll want the longest wires of the bunch in the center core layer, then the next longest group that branches out in the next layer and so on. But you also need to take wire gauge into account too, and in order to make the concentric twist work (i.e., no gaps between conductors when twisted), sometimes you need to add “ballast” wires which serve no purpose as conductors other than to fill out the twist. What I ended up with had my 4x twisted/shielded pair cables in the center as the core, then the 1st layer of 20AWG wires, next layer of 20AWG wires wrapped in the opposite direction, then the last 2 layers were all the 18AWG wires. End result was worth it though, the harness is very flexible and designed to withstand lots of stress & vibration.

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An early iteration
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Getting closer to end result, before the Raychem DR25 heat shrink.
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Re-pinned mil-spec connector reinstalled on the firewall

In addition to building out the main ECU harness, I had to integrate all the OEM wiring that rides on the removed OEM Emissions (EM) harness that still serve a purpose (e.g., speedo sensor, dash water temp gauge sensor, etc.). Fortunately, the PO didn’t hack up the OEM harnesses, so that job wasn’t too difficult, but I did have to reverse engineer the OEM cooling fan circuit, since those 4 fan relays were gone, and I wanted the fans to operate just like OEM (i.e., both fans run in parallel, 3 speeds available), with the exception that the Link is now controlling the fan on & off set points to my will. I no longer have the fan thermo switch, as it is no longer needed. Here’s a picture of the weather resistant relay box I got from Amazon, which contains 4x 40/60A Bosch 5-pin SPDT NC/NO relays that replace the OEM fan relays. I may end up relocating this box elsewhere, as it is currently taking up space that I may need for a cold air inlet duct to the air filter.


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One of the advantages of DIY wiring is that I was able to create wiring schematics that rival the quality of the Mazda FSM – see the attached PDF, which is intended to be used as “change pages” for the FSM schematics (section Z). I created these schematics using a freeware electrical CAD program called TinyCAD, which was pretty easy to use for making schematics. So if you’re wiring a Link G4+ Fury, or the newer G4X Fury (which uses the same connector & pin assignments) into an USDM FD, feel free to use it – it will save you lots of time. I was really happy when I got the Link to successfully manage cruise control for me with the DBW throttle. Had to make a few wiring tweaks to the OEM cruise wiring at the cruise main switch connector (Q-02), and the Q-01 connector where the OEM cruise electronic brain used to reside to make the OEM switch gear compatible, but that was easy – see sheet #6 of the schematic.

As for parts & materials, all in I spent around $700 for all the wire, connectors, relays and miscellaneous supplies and tooling needed to complete the wiring project. I have a spreadsheet to track all that stuff, but I avoid looking at it. :lol: Some of the vendors I’ve used that I’d recommend:

ProwireUSA – https://www.prowireusa.com/ They were my go-to place for all of the 20 & 18 gauge M22759/32 Tefzel wire, M27500 twisted/shielded pair cable, all the Deutsch DTM & DP connector kits I used, and all the pins/sockets needed to re-pin my existing mil-spec bulkhead connector and the 2x AMP Superseal connectors used by the Link ECU.

CorsaTechnic – https://www.corsa-technic.com/ These guys had all the new Mazda OEM connectors I needed along with additional/spare terminals for them, such as the X14, X05, Sumitomo CAS connectors, etc.

CrimpZone – https://www.crimpzone.com/ These guys came in handy for the larger gauge (10, 12 & 14AWG) TXL wire that I needed for power distribution, fuel pump and fan wiring, and for the 4AWG battery cable I used to restore the Engine (E) harness that carries the starter +, ground and main power wiring

Tooling – I would have preferred to invest in a set of $300 crimpers with all the different dies, but these two pictured crimpers worked great on all the closed barrel size 20 mil-spec pins & sockets, and the Deutsch DTM (18 to 20 AWG) and DTP (12 to 14 AWG) pins/sockets, and were more than capable of getting the job done for me. They go for about $30~35 each on Amazon, brand is IWISS. The IWD-20 does the size 20 mil-spec and DTM crimps, the IWD-12 does the DTP terminals.


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That PDF is incredible, Pete! I thought I did good making some half-ass notes in a binder :).

Enjoying this thread!

Dale

Thanks! When I did the FC, my wiring documentation started out as a half-ass spreadsheet & notes, that I've since created a proper schematic for. Doing it from the start is much better - and I can get the PDF schematics printed on 11x17 paper at Staples, so I have fold-out diagrams to add to my paper FSM.

Still finding some weird issues in going from the native TinyCAD files (.dsn format), and printing them to .PDF files - some of the notes inexplicably disappear during the conversion. Easy enough to fix (make the notes boxes bigger in the TinyCAD program & print to PDF again), but you don't see the error until you print them.

On this post, I’ll cover heat exchangers – radiator, IC & oil coolers. As I mentioned in the 1st post, this FD came with a big Apexi FMIC, a Megan Racing radiator mounted in an almost upright position, and an OEM single oil cooler (this FD started life as a ’93 manual trans. Touring model). My challenge was to try to figure out how I can cram an OEM or aftermarket A/C condenser in there to restore my A/C, and still have enough space to reinstall the missing bumper reinforcement bar, air guide and plastic under tray pieces.

After sourcing those missing parts plus a used AC compressor, I was ready to start taking measurements and mocking things up see if I could fit a condenser in with the current radiator configuration. It quickly became obvious that there was nowhere to fit the A/C condenser in the current upright radiator configuration with the Apexi FMIC once the bumper rebar went back in, so my options were to spring for a full V-mount setup, or revert to an OEM radiator configuration (i.e., leaning forward) with a larger than stock SMIC. Another wrinkle was I wanted to be able to fit a normal sized battery back under the hood – because, well the battery relocation job I inherited from the PO looked like a car-B-Q waiting to happen.

My 1st attempt was to see if I could make the Megan racing radiator cooperate in the OEM configuration (i.e., leaning forward). Bottom line is the upper tank on the right side of this radiator interfered with the bumper rebar before it would fully drop down to where it needed to be sitting in a fabricated bracket. And since I didn’t want to hack up a perfectly good bumper rebar, I chucked that idea and decided to buy a Koyo N-flow radiator. I had to fabricate some simple aluminum brackets for the Koyo, as the OEM pieces were long gone, but that was easy. Here’s pictures of the Megan rad interference problem and the new Koyo install & brackets I fabricated for them. Installation was rather painless, and there was plenty of space for installing an AC condenser between the Koyo radiator face and the PS cooling line loop, just like OEM.


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This shot shows where the Megan radiator interferes with the bumper rebar
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Close up of one the brackets I had to fabricate for the Koyo install
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Both brackets installed on Koyo
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Koyo as installed in the FD


Next up was oil cooling. Since this BW SXE turbo is only oil cooled, I thought additional oil cooling was a necessity, and decided to take the easy route for now – get all the parts from the OEM R1/R2 dual oil cooler setup on the used market. I scored a nice deal on almost everything I needed from Addicted Performance, so the only part I needed to buy new was the hose that goes from the front cover to the R1/R2 hard line assembly. As usual, I got that part from Ray Crowe. I didn’t have an oil temperature sensor installed before I did the dual cooler mod, to compare before & after oil temps, but now that I do (post re-wire), I’m seeing oil temps during the summer typically run below 190~195*F at the high end.

Last one up was the intercooler. After doing some mock up work with cardboard boxes, I decided to do a DIY replica of the M2 "medium" kit, which is about as much IC core as you can fit in a SMIC configuration and still keep a full-size battery up front. For the IC core, I found one that measures 18.25" W x 12" H x 3.25"D; core size is about 13"W x 12"H x 3.25"D. This is the old XSPower kit's core, that I was able to buy without the pipes from an Ebay retailer - the pipe kit that comes with the XSPower kit would have been useless with my single turbo & DBW setup anyway. For piping, I picked up some 180* and 135* mandrel bent 2.75” OD aluminum pipes, and started cutting sections out of those & mocking up the piping. End result didn’t require any complex pie cuts or too many welds – a plus since I had to contract out the AL pipe welding work. While I was in there, I also discovered a tiny coolant leak that was due to a crack in the cast AL thermostat housing, just above an NPT plug. So the same guy that welded the IC pipes repaired the crack in the T-stat housing casting. Some pictures of the process.


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Mock up of IC piping with IC core
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That silver marker line on the T-stat housing was where the hairline crack was. My welder guy welded that over, so it's now leak free and sealed up tight

Now with all the heat exchangers in their final places, it was time to build some fresh air ducting for the IC. I didn’t have anything to start with, but I purchased a used Pettit SMIC duct from a forum member. This is the smaller of the Pettit IC ducts, so I knew it wouldn’t fully cover the entire core surface of my SMIC, but I figured I'd be able to use the "snout" portion of it to pull air in from the opening between radiator & bumper support, and graft that section onto a sheet metal fabricated section for the back side to cover the IC surface. The V1 IC duct was only a partial success – it was a good proof of concept, but the old rule of measure twice & cut once bit me in the butt. Fit was a bit off, and it still didn’t cover 100% of the core surface. Here’s some pictures of my V1 ducting failure:


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This shot shows the Pettit duct installed as-is; obviously this won't work...
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And here's a test fit shot of the V1 duct I fabricated using the snout section from the Pettit duct. Not perfect, but decent proof of concept. On to Version 2...


Lesson learned; the V2 IC duct started life as a clean sheet of paper design done entirely in sheet aluminum. I posted a slightly more detailed thread for the V2 IC duct build here: https://www.rx7club.com/3rd-generati...-smic-1149118/

Here's some pictures of the new duct…

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IC duct sheet metal fabrication complete...
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IC duct after painting with a truck bed liner coating. I wanted a coating that would be tough, look decent, and also provide a little bit of thermal insulation over the raw aluminum.
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Here's a shot with the IC duct installed. After a little bit of adjusting the IC piping and tightening everything, that gap you see on the top edge closes up, and the weather stripping added to the back of the IC duct frame compresses nicely.
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Skipping a few posts into the future, here's an engine bay shot after I finished the A/C plumbing and added that aluminum cover panel

Looking forward to getting back on the road again with the FD after the salt is off the roads and the weather warms up to see where my coolant, oil and IAT's look like in the logs!

Dang Pete!! Thats some sweet a$$ work.
#garageguybuild award to you 🍺🍺 .... No send it to a shop BS here...lol
Love the make it, do it on your own mentality. Can't wait to see more of the build!
Great job.. Hope to see it at DGRR this year!

Thanks Steve!

I don't think the FD will be ready for DGRR this year - I still need to do the exhaust before that trip because 650 miles each way with it as-is on the interstate and I'll be DEEEAF! :lol:

Also need to get it to a competent tuner/dyno to get the boosted portions of the tune done right. I'm confident enough with my own abilities to get the NA mode & low load/low boost parts of the map good enough for the road trip to & from DGRR, but don't want to risk blowing anything up if I push it a bit too hard while I'm down there.

Ducting - the bane of SMICs. Looks good :icon_tup:

A/C Restoration time - part 1
 

On this post I’m going to cover the A/C restoration part of the project. When I got the car, all the A/C gear forward of the firewall was gone, but it still had a Denso evaporator core installed, and the HVAC wiring was unmolested and completely functional. Fortunately, the evaporator core ports were capped which kept it clean inside, but I decided it would be smart to remove the evaporator core so I could replace the expansion valve with a new one, flush the evaporator core with an A/C system solvent, and pressure test it on a bench to avoid any surprises later. Once it was out of the plastic core case, I verified that the core was the Denso type, with the block style expansion valve. The same OEM block style Denso expansion valves are readily available from a bunch of places, I got my new one from RockAuto for about $16.


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Denso Evaporator core, expansion valve and pipe assembly - before cleaning.
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Close up of expansion valve

Since the foam seals on the evaporator core were mostly disintegrated, I removed what was left of them, and thoroughly cleaned the plastic case where they adhere to it. To replace the foam seals, I picked up some high & medium density rubber/foam weather stripping at a few different sizes from a local hardware store. This is the common stuff that has an adhesive strip on one edge. Did a little bit of trial-and-error test fitting to figure out which density & size foam worked best, and basically reapplied it to replicate the OEM sealing design. Best fit was the 3/4” wide by 7/16” thick rubber foam pictured to the lower right here.

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The black rubber foam roll on the lower right worked best, so that's what I used.

With the evaporator core installed, next step was to get a compressor, and then figure out what to do for a condenser, dryer and all the remaining plumbing. The compressor was easy, scored a used Denso for $50, and sourced the 4x long M8x1.25 bolts from my local Fastenal shop, as I didn’t have that hardware. If you ever need rebuild parts for the compressor, it’s a Denso TV14C (more on that later…)

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Used Denso compressor, getting ready for install
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Here's the Denso part #, TV14C
Initially, my approach was to try to hunt down used OEM parts for the condenser hoses & hard piping, but I had no joy finding a used condenser that didn’t look like it came from an FD that ran a demolition derby, so I decided to go with a generic parallel flow aftermarket unit and fabricated my own bracketry to install it. Picked up a nice 24” x 12” core unit off of Amazon for about $55; it had standard -6 and -8 male O-ring insert (MIO) A/C fittings, and was sealed & capped with a pressure charge of nitrogen in it, which was reassuring when I cracked open the caps and could hear the nitrogen escaping. Here's some pictures of the condenser install:

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Overall condenser install view.
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Here's the left (driver's) side bracket - Note that I had to use "short drop" 90* fittings here to clear the frame rails.
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Here's the right (pass.) side brackets; had to grind away some of the mounting flange on this generic condenser to clear the PS cooling loop pipe.

I scored a set of compressor hoses, OEM dryer bracket, and the suction side of the hard piping from a local forum member, but when test fitting, I found that the hard pipe wouldn’t clear my turbo. Which meant that plumbing would need to be custom, but that also meant that I could find easier to replace aftermarket service parts like dryers, and place the service fittings right where I wanted them for easy serviceability. I decided to do all the plumbing with reduced barrier A/C hose and the corresponding crimped on bead lock fittings for the reduced barrier hose. FYI, reduced barrier A/C hose has the same inside diameter as “Standard” barrier A/C hose, but runs a smaller outside diameter – which makes them easier to route and fit in a tight engine bay. Same stuff all the OEMs use these days.

I had no luck finding a local shop to crimp these fittings on for me, so I invested in another tool. Picked up one of these, which does both standard & reduced barrier A/C bead lock fittings on Amazon:
For my fittings and hose, I got almost everything I needed from this shop: https://coldhose.com/ And for the one oddball metric fitting on the Denso evaporator core (smaller one), I found what I needed here: https://autoacfittings.com/. This shop also had the braze or weld-on MIO fittings I needed to rig up a way to connect to the compressor…

For the compressor hose fittings, what I did was salvage the “block” fittings from the OEM compressor hose assemblies. This website has a great how-to article on that whole process: Quality AC Hose Repair Products and Fittings from Compressor Tech The gist of it is you carefully cut off the crimp ferrule from the old hose, and remove the hose from the barb. Then you get your new ferrule & new hose, reassemble with correct orientation/clocking, and crimp on the new ferrule. At least that was Plan A, and how it was supposed to work in theory… But apparently the compressor hose Mazda used on the FD has slightly larger ID than your standard -8 and -10 reduced barrier A/C hoses I got, so no amount of lube, forcing or excessive cursing was going to get my new hoses on those damned compressor pipe barbs. Some pictures…

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Here's the OEM suction side compressor hose & hard pipe assembly; hard pipe interferes with my turbo

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Spare suction side compressor fitting (MANA?) that I used to practice - you split the ferrule with a Dremel tool as shown here.
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And here's the salvaged compressor pad fittings, ready for new hose & ferrules

So now it was on to Plan B: braze or weld on MIO fittings to the compressor pipes! I just brazed the aluminum fitting to the cleaned-up pipe end of each salvaged aluminum compressor hose fitting, here’s a picture of the end result.
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Both compressor fittings with MIO ends brazed on

This post continues in Part 2, apparently there's a picture limit...

A/C Restoration, Part 2
 

Now it was time to select a dryer, a binary switch and plumb it all together. I selected a generic dryer that fits in the OEM dryer bracket, and has a port for a binary hi/low pressure switch. Both the dryer and switch selected will work with R12, R134A and R152A (aka: computer duster gas), so I can charge the system with any of those. Here’s the dryer & binary switch kit I got: https://www.tbiproducts.com/index.cf...prod/prd63.htm

And here’s some pictures of the fully plumbed system…

https://cimg6.ibsrv.net/gimg/www.rx7...d53a06f289.jpg
Here's the Dryer & Binary Switch install. I added a 2nd high side service fitting on the input side of the dryer because a HVAC tech buddy said it's handy to have a 2nd fitting here for troubleshooting some A/C problems


https://cimg8.ibsrv.net/gimg/www.rx7...78cc83016e.jpg
Close up detail of the low & high side service fittings - easy access baby!


https://cimg4.ibsrv.net/gimg/www.rx7...37765f3d29.jpg
Detail of how I routed hoses around shock tower.Can't see it here, but the low & high sides connect to the evaporator core with 45* fittings


https://cimg2.ibsrv.net/gimg/www.rx7...a631cc79b3.jpg
This shot shows how I routed the hose from the output side of the dryer and the suction side of the compressor along the IC support beam.

With that all done, it was time to pull a vacuum on the system and hope that it holds…. It didn’t. I found the first leak by partially charging the system with 1 can of duster gas (R152A), and hunting for it with my cheapo Harbor Freight electronic sniff tester. Quickly found the leak at my brazed-on MIO fitting on the compressor discharge pipe. Not too surprising, this was the 1st time I brazed aluminum. I yanked off the compressor discharge & suction fittings, un-brazed the MIO fittings, cleaned up the pipe ends, got a couple of new MIO fittings and brought them all to my local welder guy to get them welded instead.

With the welding done, I reconnected the lines and pulled a vacuum – it held, but not 100%. After about 3 hours, the vacuum dropped about 10 inHg (from about 29~30 inHg), which is a slow leak. Another partial charge with duster gas, and with the compressor running (and actually cooling the car’s interior), I found my slow leak at the compressor shaft seal with the electronic sniffer.

After consulting with the FSM, I think I’m going to try to rebuild the compressor, assuming I can find all the required replacement seals/parts needed. If that doesn’t work, I did find a new compressor here: https://ackits.net/product/14-3662nc/ so that’s Plan B.

Nice work
 

This is a great build. Very similar to my build in many ways. My goal was the same as yours and I have also taken the time to review some of the parts. This is my type of build so I am excited and will stay tuned. Brap on brother.

Awesome stuff here, Pete!

Dale

Cat-back time
 

Sometimes you get lucky and things really fall into place! Back to my 1st post, I mentioned how damned loud my FD was due to the custom fabricated exhaust the PO put in there, and I've been looking for either an RB cat-back or Tanabe Medallion cat-back to squelch the racket & drone. So I just pulled the trigger on the Tanabe - got it from Amazon for $398 shipped, sweet!

https://cimg4.ibsrv.net/gimg/www.rx7...35d90bd6c9.jpg
Unpacking the new Tanabe cat-back

Now since the PO told me that he didn't bother to design his cat-back & mid-pipe exhaust to be interchangeable with the stock parts, I was fully expecting to need to do some fabrication work to be able to install the new Tanabe. My plan was to get the Tanabe cat-back, and the RB 3" resonated mid-pipe, and then modify the custom DP to mate up with it. Today I decided to test fit the Tanabe, and was overjoyed to find out it dropped right in, fits perfectly and mates up with the PO's custom straight thru mid-pipe section! Some pictures...


https://cimg6.ibsrv.net/gimg/www.rx7...e9496cb20d.jpg
Tanabe fits the OEM hangers perfectly
https://cimg4.ibsrv.net/gimg/www.rx7...ac964879ed.jpg
WooHoo!!! It lines up and will bolt in!
https://cimg2.ibsrv.net/gimg/www.rx7...19acbb6d92.jpg
And bolts in & torqued up

So now I'm wondering just how "custom" my existing 3" DP & mid-pipe section really is? The Tanabe cat-back alone has taken a bit of the bark out of the exhaust's sound, but I think it's still too loud & drones too much on the highway - going to need a resonated mid-pipe to squelch it a bit more and finish the job. Based on the following pictures, do you guys think the RB pre-silencer/mid-pipe combo will bolt right in here? If not, it looks like there's plenty of room for me to get a generic 3" resonator? Thinking a Magnaflow, Borla, etc. if I have to go that route.


https://cimg4.ibsrv.net/gimg/www.rx7...01477a90d4.jpg
Here's a shot of the PO's mid-pipe where it mates with the DP.

Man I am very excited for you!!! Let me know how it sounds. I was thinking of going big single tip, but not sure how it will sound next to my RB dual tip.

Thanks, I should have thought to grab a "before & after" recording of the sound with my phone before I yanked the old cat-back off! It is definitely a LOT quieter than it was before, so I think the Tanabe would sound comparable to the dual tip RB system, if all things forward of the cat-back were the same. But mine still has that raspy drone, which I attribute to the PO's straight thru mid-pipe - I think if I splice a good resonator in there (i.e., largest can volume 3" in/out resonator I can fit), it will squelch all the annoying droning and high frequency raspy noises.

FWIW, RB makes a single tip version of their dual-tip cat-back, I've heard both types on similarly equipped FDs, and I couldn't hear a difference between the two.

Funny how long ago the big exhausts were sought after and now most of us want a quieter exhaust. I guess I really need to look into some other options because I wouldn't mind my RX-7 being a bit quieter.

Sound bite - Tanabe catback
 

For those interested, here's a link to a quick (<10 seconds) video/audio of my FD's Tanabe cat-back exhaust.

https://drive.google.com/file/d/1SBd...ew?usp=sharing

Clip was taken maybe a minute or so after starting the car, and pulling it off the rack, so engine is still warming up at high idle, around 1300 RPMs or so. Also, this is with a basically straight 3" piping run from the single BW turbo to the cat back (no cat/no resonator/pre-silencer). It's still orders of magnitude quieter than the crappy Dynaflow muffler the PO had in there, but I think it would help to put a good resonator in the mid pipe section to filter out the high raspy notes when I get on the throttle, and the resonant droning sound you get at steady highway speeds over 70.

Got a link to that a/c condensor? i'm on the market for one...

Sure, the condenser was a part I picked up from Amazon:
Due to the tight space available, to plumb this thing you'll need to to use "short drop" 90* fittings (as shown in my pictures), or fabricate hard lines instead.

Exhaust sounds good! Might be worth looking at a high-flow cat to reduce noise and stink as well.

Dale

Hey Dale,

I'm definitely going to put in a 3" resonated mid-pipe section, either the Racing Beat one or the similar resonated mid-pipe that Banzai racing sells for about $30 less. Either one should do a great job squelching the remaining raspy high notes I get when I stand on it at WOT, and the annoying highway drone resonance tones at cruise - both mid-pipes feature large volume, oval resonators, with all SS construction & mandrel bends.

Putting a cat back in would probably fall into the "too hard to do" category, since I'd think an air pump would be needed to get any kind of reasonable durability out of a cat. With the big BW single turbo, there's no room for an air pump, unless I rig up an electric air pump somehow. As for the stink, it's not too bad - once warm, it's happy idling just a bit richer than stoich, about 0.95~0.975 lambda, and no visible smoke now that I'm getting the OMP pre-mix delivery map dialed in correctly. In fact most of the stink there seems to be more a function of what brand pre-mix I'm using, and how much it's burning. Maybe the expensive Idmitsu pre-mix will smell better? :dunno:

I've been running an SMB high-flow cat from Australia for at least 10 years now - big time reduction in stink and noise, flows awesome, and zero problems with no air pump. A good quality high-flow cat won't need the air. If you are looking to pass emissions you would need the air to help out - it helps the process burn more effectively.

Also, FYI, the electric air pumps like the RX-8's aren't designed to run full time. The RX-8 air pump only runs for 15-20 seconds on stone cold morning starts, that's it. Source: dailying an RX-8 right now. If you tried to run it full time it would die a quick death, it's only designed for intermittent use.

For some reason a number of years back something flipped in the smell part of the brain and no-cat exhaust stink drives me NUTS, it sticks in my nose forever too.

Dale

I agree.. I'm glad I have my catalytic converter. I've driven RX-7s without one and the smell is nauseating.

check out the Bonez high flow from RX7.com. It doesn't need the air pump but is provisioned to work with one.

Resonated Mid-Pipe installed - quiet at last!
 

So I ended up getting a great deal purchasing a lightly used PFS resonated mid-pipe from a Canadian forum member. This one is all 3" mandrel bent 304 stainless, with a Magnaflow resonator; seller wrapped it with heat insulation to reduce the heat into the cabin. Fit perfectly, and completely squelched the remaining racket I had when it was a straight thru pipe only. Pictures of the install:


https://cimg2.ibsrv.net/gimg/www.rx7...52ff8c419d.jpg
https://cimg4.ibsrv.net/gimg/www.rx7...3b728ec17f.jpg

It's so much nicer driving a relatively civil FD - no more headaches on the highway, unwanted attention and I can hear my stereo and carry on a conversation with a passenger. The header wrap is also a nice perk, as there's less heat intruding into the cabin - shifter & tunnel area feels noticeably cooler than it was before. Now I just need to find a local fabricator who can recirculate the external waste gate dump tubes back into the down pipe for me. That will become more of a necessity as I think I'm going to change out the my WG springs soon to allow for lower boost levels (~9psi at the low end), and tune a few different boost control profiles into the Link ECU.

Cold Air Intake - or how to cram 20 pounds of s**t into a 5 pound bag
 

So with the crappy weather trashing most of the plans I had for the Memorial day weekend, I got busy creating a cold air inlet plenum for the FD. With the single turbo sucking its air thru a shorty cone filter and a cramped heat soaked engine bay, it wasn't doing my IAT's any favors. From the data logs on my Link G4+. I can tell that the IC is doing its job, but once the engine bay gets good & hot, the IATs keep going up because there was no separate cold air supply for the air filter.

I ended up taking advantage of that roughly 1-1/4" wide sliver of space between the radiator and the frame rail that is normally blocked with a piece of foam in a stock FD (I never had that on mine). Started getting crafty with some sheet aluminum and pop rivets to build a plenum that would direct cold air from in front of the radiator into a box enclosure that would surround the shorty cone filter on my turbo's inlet. Here's pictures of the process...


https://cimg7.ibsrv.net/gimg/www.rx7...8236c58ca3.jpg
This is the nearly completed base section of the plenum. It was like making aluminum origami!
https://cimg3.ibsrv.net/gimg/www.rx7...bc02a1d1a2.jpg
Here you can see how the "snout" side of the plenum fits in the space between the frame rail and radiator assembly, so it can direct cold air from in front of the radiator into the air filter
https://cimg4.ibsrv.net/gimg/www.rx7...1f2b444aff.jpg
Picture #1 of the mock-up and test fitting under way.
https://cimg0.ibsrv.net/gimg/www.rx7...9245fe904f.jpg
Picture #2 of the mock-up and test fitting under way. My hard line to the boost solenoid interfered with the lid section, so I'll be switching that to silicone hose. 90* brass barb fitting is already installed
https://cimg9.ibsrv.net/gimg/www.rx7...f0cd6bdc7f.jpg
Picture #3 of the mock-up and test fitting under way. Almost done, fan relay box & OEM relays fit fine.
https://cimg7.ibsrv.net/gimg/www.rx7...e92d4d8d8d.jpg
And here's the completed installation!

Looking forward to taking it out for some test runs to log data and evaluate how this works to solve my IAT problem. If I can get IATs in the ballpark of about 20~30*F above ambient air temps, I'd call that success.

Oh hell yeah, you will see a decrease in temps no doubt. My red neck engineered plate added to Pettits cool charge was around 10°f... This looks awesome!! Looking fwd to the results.

WOW that's some impressive fab work, Pete! Did you use some sort of sheet metal brake to bend everything?

Dale

Thanks Dale! I do have a small Harbor Freight bending brake which is fine for pieces under 12" long, though it's kind of a PITA to setup and use. More often than not, I find it easier to improvise my own bending brake with pieces of AL square stock, some C-clamps and the workbench and/or vice. Another handy tool to have is one of those seam pliers the HVAC guys use for duct work - makes quick work of the small pieces less than 3" long that need a bend.

After test driving it today, I'm finding that it's meeting my IAT reduction targets - kept my IATs within 20~30*F higher than the ambient air temps even with the engine bay heat soaked. But there is a mechanical flaw I need to fix - since the plenum is just press fit in between the radiator and frame rail, engine torque, vibration & bumps from driving around make the whole box assembly want to twist & move around some. And since the box around the filter and the plenum is one rigid part, and the clearances are tight, the upper right corner of the box tends to dig into the IC - already bent a few fins. :banghead:

So I'm re-thinking a V2.0 design... Use a flexible section to couple a separate lower plenum section to an upper air filter box. Then I could rigidly bolt the lower plenum section to the body, and bolt the upper filter box section to the turbo itself - I can either use the unused threaded hole on the compressor housing for the turbo speed sensor port, or design the back plate part of the box to sandwich fit between the compressor housing & cone filter (tightening the filter secures the box around it; a removable box lid allows me to get to the worm gear clamp). And maybe that old oval FC cold air intake rubber coupler I have laying around might make itself useful as the flexible coupler between the sections I need!

If you really want to go down the rabbit hole with development on this, you can get a differential pressure gauge that can show the difference in air pressure in the air box and ambient. That can show if you have a restriction in the air box, it measures in inches of water and is a good way to find out if you have a restriction, either the opening isn't big enough or what have you. A small difference sometimes can translate to a substantial difference in horsepower, especially at high RPM.

Dale

Nice work Pete!! Definitely some awesome #garageguywork 👍

.

Cold Air Intake Version 2 - still cramming 20lbs of s**t in a 5 pound bag
 

Although it worked to bring down IAT's, the version 1 box I made had a significant flaw - being a rigid design, engine torque and bumps/vibration was causing it to bend & deform. So it was back to the drawing board for version 2. The v2 design concept is similar, but it separates the air filter box from the plenum, so now there's a movable joint between the two.

Here's a shot of all the parts after fabrication was mostly finished. To the left is the plenum piece (aka - the snorkus) which is just a duct that directs cold air from in front of the radiator past it and into the engine compartment near the turbo. To the right of that is the air box & air box lid - this obviously encloses the air filter, and is rigidly mounted to the turbo using an unused threaded hole on the compressor housing that is for an optional turbo speed sensor. The part in the middle foreground is what makes this work - a plenum coupling that provides an air path from the snorkus plenum into the air filter box, while allowing some movement between the two. Basically the rectangular hole in the bottom side of the coupling slides over the top rectangular "probe" of the snorkus piece. A bit of weather strip foam insulation was added there to keep it relatively air-tight, but still allow some motion between the parts. The side of the coupler plenum has a rectangular hole that mates up with a corresponding hole in the air filter box


https://cimg4.ibsrv.net/gimg/www.rx7...83a5c20b67.jpg

And here's some shots of the test fitting and installation under the hood...


https://cimg6.ibsrv.net/gimg/www.rx7...939e3845f2.jpg
Air box under construction test-fit. This shows how it mounts to the turbo via a small bracket I fabricated to take advantage of an existing threaded hole on the compressor housing.
https://cimg1.ibsrv.net/gimg/www.rx7...d006821c2a.jpg
Making progress on the test fittings, cracked the code on the plenum coupling piece - took lots of trial & error mock-ups to make that sucker fit!
https://cimg8.ibsrv.net/gimg/www.rx7...6ec1aa08c8.jpg
Nearly finished - almost everything is back together
https://cimg5.ibsrv.net/gimg/www.rx7...e06d05b250.jpg
And done!

Wow, that is some serious work you have done! You have really refined the car and made it much more drivable. Ironically I was living in SC at the time when I was shopping for an FD. I messaged the previous owner about this car asking what it needed to get the AC working again. He promptly told me AC does not work in FDs and since I was a noob he would not sell me the car. Good thing I did not buy it, because I got a car that works better for me. Glad to see you were able to put AC in the car and are enjoying it!

Thanks! The A/C isn't completely done just yet though - I'm still chasing leaks! Last time I posted about the A/C, the system was basically done, but I found a slow leak at the shaft seal of the used compressor I picked up. But the system was cooling the cabin a bit on a partial charge while I was hunting for that leak, so partial win - at least I know it will work once it's leak free.

So I found a rebuild kit for the Denso TV14C compressor, and with the FSM to guide me, I attempted to replace the shaft seal. Looked easy enough, but it ended up leaking worse than before... or so I thought (more on that soon). Here's a picture of the rebuild parts:

https://cimg1.ibsrv.net/gimg/www.rx7...45bf9d4e00.jpg


So thinking the used & now rebuilt compressor was toast, I went and purchased a new aftermarket compressor from these guys: https://ackits.net/product/14-3662nc/

New compressor arrives, and as promised by the vendor, it came sealed with a 100psi charge of nitrogen in it to test & verify it's leak free before installing. Since one of the caps had a Schrader valve on it, I stuck my tire gauge on it, and sure enough 100psi, good compressor! So now I yanked out the used compressor and installed the new one, and went to pull a vacuum - and it won't hold, WTF?

So now I pull a vacuum and charge with 1 can of duster gas again to go leak hunting with the sniffer again. Since I was more confident the new compressor was good, this time around I was a bit more deliberate in using the sniffer, and I isolated the leak to joint where the compressor pipe on the suction side is brazed onto a male insert O-ring (MIO) fitting where my hose connects to it. So more than likely, my rebuilt compressor was fine - due to the proximity of that pipe and the compressor pulley/front, I probably misdiagnosed that same leak before using the sniffer. Anyway, this was my 1st attempt at brazing aluminum, and apparently the learning curve is steeper than I thought! The brazed joint developed a hairline crack, probably from me R&R'ing the compressor a bunch of times. In the interest of getting this job done, I'll be cleaning up that pipe, getting a new MIO fitting and get my local welder guy to weld it for me, which is what I did for the discharge pipe.

Woo Hoo!!! Working COLD A/C!!!
 

I finally got this damned A/C system leak free and it held vacuum overnight! As discussed in previous post, I had my welder guy weld a new MIO fitting to the same suction pipe that I originally tried brazing a MIO fitting to, that attempt failed with a hairline crack. Anyway, I went ahead and charged the system with R134A. Since this system has an aftermarket condenser, dryer & custom plumbing, the OEM R134a capacity specs to charge by weight didn't apply, but close enough to tell me I'd need at least 2x 12oz cans of R134A, and it would need to take at least 1 full can. So the charging procedure was as follows:

1. Start with a solid vacuum - run the vac pump for at least 30~60 minutes to boil out every last molecule of air/moisture.
2. After bleeding the yellow hose, engine & A/C off, let the vacuum suck in the entire contents of the 1st R134A can as a liquid via the LOW side (can inverted, valve fitting on bottom). That gets ~12oz in, and is enough to get the compressor to run. Close the low side valve on the manifold gauge when done.
3. Hook up the 2nd can to the manifold gauge set & bleed the yellow hose. This time we're charging as a gas (can right side up, valve fitting up top). Start engine & flip on A/C to MAX cooling, max fan, & RECIRC; Stick a thermometer (I used a DVM with a thermocouple temperature probe) in the center dash vent to monitor outlet temps. Also have a hose handy to mist down the condenser to help facilitate the charging process along, and a helper to hold engine revs at a steady 2000 RPMs.
4. On 1 can, the compressor should be running, and probably cycling a bit; crack open the low side wheel on the manifold gauge when the low side pressures bottom out (low side pressures will quickly rise as R134A gets pulled in). Goal here is to slowly throttle the R134A in while keeping an eye on your vent outlet temps and low/high side pressures. You're going to slowly charge until the outlet temps bottom out. My vent temps bottomed out right around 40*F while charging. If the car (and condenser) is starting to heat soak, give the condenser a spritz with the hose. Depending on the ambient temps at the time, the correct pressures can be found in the FSM in a chart. In my case, it was about 87*F, so I was shooting for a high side pressure around 220psi, and a low side around 32psi at full charge.


https://cimg5.ibsrv.net/gimg/www.rx7...38f5e2e7f9.jpg
Vacuum held at 29~30 inHg overnight

Since the cabin is now cooled with A/C, I figured it was time to do something about radiant heat under the hood, so I picked up a PTP Turbo blanket; went for the "lava" version, which is supposed to handle significantly higher contact temperatures than the standard versions. Next up will be to wrap the DP, but that job will have to wait until I get around to getting a fabricator to recirculate my open dump waste gates into the DP.


https://cimg5.ibsrv.net/gimg/www.rx7...268246c144.jpg


I have to say getting the A/C working again makes this car a joy to drive - Took a little road trip to NJ for a rotary event at JPR Imports this past weekend, and it was nice driving there & back with a nice chill going on inside! Not having sweaty balls in the FD on a 90*F swampy day is priceless :nod:

Nice update Pete!
Glad to hear she cooling you down on them road trips.
I love having a/c in mine 👍

Congrats on your ac and the air box. The airbox looks super cool and I know the goal was to lower IAT but were you able to do so with out restricting the air flow to the air filter?

Thanks Steve! Yeah, the A/C really makes the car more enjoyable!

Thanks, I'm sure there is some restriction associated with the airbox, but I think the net effect of lower IATs will result in an overall performance gain and a safer/more reliable tune. When I get this thing on a dyno, it might be a good idea to test it with & without the airbox lid on to try to characterize the airflow vs. IAT trade off. The logs are telling me the air box really works well at lowering the IATs. When it was just the open cone filter, IATs would climb pretty quickly to the 120*F range on an 80~90*F ambient temp day, and soar way above that when heat soaked sitting in traffic. Now with the box, the IATs won't go much above 100*F on the same 80~90*F ambient temps, and they'll stay there as long as I'm moving. And the real key is that even if the car starts to heat soak when sitting in traffic, the IATs don't rise as high or as quickly as they used to, and they will quickly drop back down to the lower 100*F range once I'm moving again (i.e. about 10~20*F higher than ambient).

I would love to see the results on the dyno. I have an open cone in the engine bay so I am thinking of doing something similar to what you did.

Walbro 450 fuel pump & Fuelab filter install
 

So I finally got around to knocking off two more things on my FD's pre-tuning punch list - fuel pump & fuel filtration upgrades! Per the previous owner, he didn't get around to doing anything with the fuel pump, so I was expecting to find an OEM FD pump in there. Much to my surprise, an older Walbro 255 was in there, and I was also happy to see the tank & pump hanger were pretty clean and free of rust :icon_tup: Picture of the old Walbro & hanger:


https://cimg6.ibsrv.net/gimg/www.rx7...b872e4220d.jpg

I decided on purchasing a Walbro 450, and the IRP pump install bracket kit to make it an easy & relatively painless install. Ended up purchasing the Walbro 450 pump with sock & install kit from Banzai racing, and get just the bracket kit from IRP.

Fuel pump & Install kit - Walbro 450 LPH E85 Fuel Pump

IRP Walbro 450 mounting bracket - https://www.irperformance.com/produc...-pump-adapter/

Since the hose that came with the pump install kit Banzai provided didn't fit the hanger hard line (ID is too large), you need to get less than 1 foot of 5/16" ID submersible fuel hose locally to finish the job - look for the SAE 30R10 markings to verify that your local parts guy is giving you the right stuff. Oh, and you'll have to cut the OEM hanger fuel tube above the bell-shaped end that connects to the OEM pump to install the Walbro 450 (and similar pumps).

For wiring the pump, I didn't want to risk running the puny OEM electrical bulkhead connector because it can't handle the current. So I basically did the same thing that Steve did with his build - the ATL wire-thru bulkhead fitting that lets you pass 12~10 AWG Tefzel (PTFE Mil-spec wire) right to the pump. Here's a link to his build thread for pictures; I was too lazy (and stinking of fuel) to shoot pics of mine, but it looks the same - https://www.rx7club.com/build-thread.../#post12397093

The only difference between my setup and Steve's is I used the fuel submersible Metri-pack connector that came with the Banzai kit instead of butt connectors to terminate my wires to the pump, since my pump came with the mating connector already installed. Here's some pictures of the build process. Hardest and most nerve-wracking part of it was finding a good place to drill a hole in the OEM fuel hanger assembly for the ATL fitting - there isn't much space where it will fit and not interfere with something else when installed. Also drilling the hole just right is critical - too large, and it won't seal!. I used a step drill bit, followed by a "step-less" multi-size drill bit to ream it out to the precise diameter needed, which was somewhere between 5/8" and 11/16".


https://cimg7.ibsrv.net/gimg/www.rx7...5eb17e9159.jpg
Preparing to drill the hole...
https://cimg5.ibsrv.net/gimg/www.rx7...138cd6a1e8.jpg
Hole drilling done!
https://cimg4.ibsrv.net/gimg/www.rx7...a88c78ac9e.jpg
Pump installed, detail of new wiring
https://cimg1.ibsrv.net/gimg/www.rx7...39a54b32c3.jpg
And covered and plugged in

With the fuel pump installed, it was on to upgrade fuel filtration. Issue with the stock FD fuel filter is it probably doesn't filter much below 10 micron particle size, at best. Bosch, ID and just about every other fuel injector manufacturer are specifying filtration in the 4~6 micron range to keep their injectors happy. So I decided on installing a Fuelab 81831-1 filter. This one filters down to 6 microns, has more than enough (like double) the flow capacity of my Walbro 450 LPH pump, and uses -6AN fittings on each end. The filter element is also replaceable (about $40) and readily available at Summit, JEGS and probably Amazon. Picked the filter up on Amazon -
To mount my new filter in an easily serviced location, I picked up this ID F750 filter bracket kit sold by JP3 motorsports - https://jp3motorsports.com/collectio...filter-bracket

I had to drill one hole in the JP3 bracket to adapt it to mount my Fuelab filter using the saddle bracket provided with the filter. Pictures show the gist of the install; the filter outlet is on top, and routes via hose to the existing hard line where the stock filter used to go. In the inlet (bottom) of filter, I ran hose direct from the tank hanger hard line outlet nipple as the hard line where the OEM filter connected to was too clumsy a routing. To plumb to the filter, I used a couple of 6AN to 5/16" hose barb 90* adapter fittings.


https://cimg5.ibsrv.net/gimg/www.rx7...a9c4aa4a2f.jpg
Here you can see where I had to drill the additional hole on the JP3 bracket to mount my Fuelab filter
https://cimg8.ibsrv.net/gimg/www.rx7...275cfa5bd6.jpg
And this shot is the filter installed on the bracket, using the saddle bracket that came with it.
https://cimg3.ibsrv.net/gimg/www.rx7...1b6e0aa129.jpg
Bracket & filter installed on the diff carrier/frame, prior to fuel line plumbing
https://cimg1.ibsrv.net/gimg/www.rx7...1a57737c5c.jpg
And installed & done!

The hardest part of this job was just getting the old OEM filter out, and the hoses off, what a PITA, WTF Mazda? :banghead: Next time it will be easy-peasy! :nod:

Very Clean!
 

Strong work as always Pete thanks for sharing!
Running a upgraded or bigger pump and then using the stock in pump wiring is asking for trouble!
These bigger pump pull alot of juice.
I just did a status check on my ATL bulkhead fitting last week.
Wanted to make sure there's no seepage or leaking and everything is still bone dry :icon_tup:

I gotta do that fuel filter relocation too,,, love how yours turned out.


Steve

This is something I'm needing to do and also needing to do on one of the other guy's FD's here (Jason). Thanks for the pics, where the hole in the fuel pump hanger goes is BIG TIME helpful!

Hope you have the car up and driving soon, that sucker is going to be a blast to drive. Also really hoping it's all 100% for DGRR next year, I really want to see it!

Dale

^That's good to know, you've had yours in for about a year now? The potential for fuel wicking up the wires past the seal does worry me, I haven't tested it on a full tank yet.

Figuring out where to drill that whole really was the hardest part of the job. Given the size of the ATL bulkhead pass thru, and all the crap on the top & bottom sides of the hanger top, the location I got was literally the only place you can drill a hole that big that allows the ATL to mount up without interfering with something else.

Interior Restoration & Upgrades, part 1
 

So tonight's topic is the FD interior. My FD interior needed lots of restoration help when I got it - here's a few pictures of what I started with...
https://cimg4.ibsrv.net/gimg/www.rx7...b598b3e6fd.jpg
No radio, no speakers, but more gauge holes than I will ever use... and I'm not digging the lightweight purple shift knob
https://cimg5.ibsrv.net/gimg/www.rx7...bef0ee579f.jpg
Here's the hatch area that once had a Bose system in it.

Fortunately the instrument cluster hood was almost brand new from the PO, so it wasn't too hard to remove it partially so I can get that HVAC/radio panel out. I sourced a used HVAC/Radio panel, shifter console panel and a new Redline leather shifter boot from a forum member. I refinished both panels & ashtray assembly using the SEM Trim Black paint, which matches the color & smooth texture of the cluster hood perfectly. For the refinish job, I used Easy-Off oven cleaner to strip the rubbery coating off of the used plastic parts - let them marinate a bit, and wipe off with a scotch-brite pad. Then wet sand panels with 1000/1200/2000 grit sandpaper, wash with a water based de-greaser and a final wipe with alcohol and dry prior to applying the SEM paint in several light coats.

For the sound system, I got a 2DIN format Kenwood Excelon DMX706S with Android Auto/Carplay support. I mounted that in the dash with a Pioneer ADT-VA133 double DIN install kit/cage, which made the installation simple. The factory radio wiring was a bit hacked up, so armed with the FSM wiring diagrams, I built a little sub-harness to integrate the factory wires to the radio with Deutsch DTM connector. For front speakers, I installed Infinity Reference series 6-1/2" round two way speakers using mounting adapters found on Amazon. For the rears I mounted 6x8" Infinity Reference 3-ways using DIY speaker brackets that I fabricated, and DIY speaker grills that repurposed the old Bose cubby bins. The "how to" on the brackets & grills can be found in these two forum threads:

https://www.rx7club.com/3rd-generati...ed-fd-1140400/
https://www.rx7club.com/3rd-generati...ed-fd-1141509/

And pictures of the radio install, and rear speaker grills...

https://cimg3.ibsrv.net/gimg/www.rx7...751c238175.jpg
Radio installed with refinished HVAC & shifter panels
https://cimg7.ibsrv.net/gimg/www.rx7...037ee591ae.jpg
DIY Speaker grills installed

With that done, I had a weighted spherical aluminum shift knob laying around that fits, so I used it to get rid of the purple one. It had a great shift feel, but sucked when the interior was too hot or cold - my bare hand would either get burned or frozen. So I scored a nice OEM FD knob, also weighted that had its leather recently refinished from a forum member, made for a nice upgrade - more pictures...

https://cimg8.ibsrv.net/gimg/www.rx7...307d8e6a55.jpg
Aluminum knob
https://cimg9.ibsrv.net/gimg/www.rx7...749a1ae479.jpg
Leather refinished FD OEM knob

To fix up the hatch area, and reduce cabin noise, I applied some of this 80mm Noiko material to the floor of the hatch area, this stuff is very similar in design, construction and application to the more expensive Dynamat stuff. Link to Amazon: I also applied this stuff inside the door panels, and under the bins. Overall, my FD is still a noisy car, but it has substantially improved from what it was before.

On top of that, I had just had my dishwasher fail, so before I tossed the DW, I had the bright idea to repurpose the sound insulation blanket from it and use the material on the trunk floor for additional sound insulation. It weighs practically nothing, was easy to cut & fit, and it helped fill the gaps and "flatten" the floor for the final cosmetic step - covering the hatch floor with the hatch carpet mat that Garage Alpha sells. Pictures of the process and end result.


https://cimg2.ibsrv.net/gimg/www.rx7...7ec77a79e2.jpg
That silver matting on the top is the Noiko sound insulation. It's a rubbery self-adhesive substance, you just apply and use a roller to flatten it down
https://cimg1.ibsrv.net/gimg/www.rx7...563310d45c.jpg
And here's the repurposed dishwasher sound insulation that I cut to fit the floor area. It simply lays in there, and is about 1" thick when uncompressed
https://cimg2.ibsrv.net/gimg/www.rx7...b7af62e931.jpg
And here's the Garage Alpha carpet mat to finish the hatch area.

That's it for tonight, next time I'll cover my tan-to-black plastics refinishing work

Interior restoration, part 2 - Tan-to-Black plastics & seatbelt restoration
 

On tonight's post, I'll cover the tan-to-black refinishing of most of my interior plastic panels, and seat belt restoration. My tan seat belts were pretty grungy, especially the driver's side, and showing some frayed edges. Since my attempts at cleaning them didn't help much, and I didn't like the frayed edges, I decided to ship them off to Safety Restore to have the belt webbing replaced with new OEM webbing, and get the belt mechanisms refurbished for 100% proper like new operation. Link: https://www.safetyrestore.com/

That job was pretty easy - just remove the belts, ship them off to Safety Restore and wait for the newly refurbished belts to return. Cost me less than $200 all in, including the shipping, and I got them back less than a week after I shipped them out. The only catch is for old cars like the FD, they can't source parts like the seat belt tongue. So since I wanted to change the tan webbing to black, I needed to find some black FD seat tongues for them to use. You can read a bit more details on how I accomplished that task here - https://www.rx7club.com/3rd-generati...-cars-1145595/

Bottom line is if you have no luck finding an actual FD seat belt tongue in black, and nothing available in the junk yard works, you can buy an inexpensive pair of DOT approved "seat belt extenders", and harvest the tongues from those. I picked up a pair from Ebay for about $17 that did the trick. Some pictures...

https://cimg7.ibsrv.net/gimg/www.rx7...ed48fbc4ac.jpg
Above is a picture of the OEM tan seat belt tongue, next to the Ebay "seat belt extender" tongue that I harvested. Works just fine with the FD seat belt latch.
https://cimg6.ibsrv.net/gimg/www.rx7...37399e7f50.jpg
Restored driver's side belt assembly

I did much of the tan-to-black restoration while I had most of my interior apart during the spring of 2020, while I was rewiring the ECU, and "de-modding" the rear bin battery relocation. Process I used to refinish the plastic panels is similar to what is described in at least a half dozen "tan-to-black" threads here on the forum, but here's the summary:

1. If panel has that '93 style rubbery coating/crud on it, strip it off with Easy-Off oven cleaner spray, let it marinate a bit and use Scotch bright pads to remove the stubborn stuff.
2. Wash panel thoroughly with a good water based de-greaser. If it's a smooth panel, wet sand the panel with 800/1000/1200 grit sandpaper. Repeat the wash & de-grease step after sanding.
3. Air dry the panels.
4. Using SEM paint, apply paint in several light coats. Follow the directions on the can to the letter. I found this stuff drys quickly, so at about 70~80*F low humidity days I did this, it only took about 10 minutes between coats.
5. After the final coat, put the panel somewhere safe & dust free so the paint can cure for at least 24 hours before attempting to re-install it.

So far I've tan-to-black refinished all the cabin plastics with the following exceptions: Seat plastic parts; hatch/gas tank release piece on the floor; headliner trim & related bits. Haven't decided what to do with the seats, carpet and headliner yet. There's a local shop that tells me they can actually recolor/repair my seat leather to look & feel as good as new for about $500, and there are a few online sources for replacement leather seat skins that I could DIY install. Did that job on my FC some 15 years ago and those seats still look & feel like new. My carpet is in pretty good shape, so since replacing the OEM carpet is a major PITA, I'm leaning towards keeping the seats tan, leave the carpet as-is and just get some new mats and call it a day. I kind of like the way the tan leather pops in the mostly black cabin. As for the headliner, I could convert that to black too, but the tan headliner is kind of growing on me - the lighter color contrast up top gives me the optical illusion that the cabin is less cramped than it is, and you really can't see much of the tan headliner from outside the car. Anyway, here's a bunch of before & after pictures!


https://cimg9.ibsrv.net/gimg/www.rx7...261c85a25a.jpg
Before shot of door panels, prepped & ready for SEM paint
https://cimg2.ibsrv.net/gimg/www.rx7...747f98e832.jpg
Before shot of rear quarter trim
https://cimg4.ibsrv.net/gimg/www.rx7...ee3e5c2557.jpg
Quarter panel spraying in process...
https://cimg1.ibsrv.net/gimg/www.rx7...4a220b0493.jpg
A bunch of the smaller refinished panels
https://cimg4.ibsrv.net/gimg/www.rx7...f941379df1.jpg
Refinished bins
https://cimg7.ibsrv.net/gimg/www.rx7...da2eb99193.jpg
Refinished door panels
https://cimg6.ibsrv.net/gimg/www.rx7...9c111e1b76.jpg
Refinished bins, quarter trim and hatch divider installed
https://cimg9.ibsrv.net/gimg/www.rx7...36b278345f.jpg
Driver's side door panel installed
https://cimg7.ibsrv.net/gimg/www.rx7...99166bf42f.jpg
View of cabin from passenger side
https://cimg2.ibsrv.net/gimg/www.rx7...10c9e08c4e.jpg
My solution to the battery mod hacked passenger side bin - using a tool bag to restore the hacked bin to functional. It ain't pretty, but it works!

For that storage bin, what I did was repurpose a small tool bag I had to form a soft bottom to make the bin functional again. With the tool bag wide open, it fits nicely over the remaining plastic edges that the PO left when he hacked the bin for the battery relocate mod. Then I just drilled a few holes in the plastic at a few points around its perimeter, and fixed the open tool bag to it with some zip ties. Ugly, but it does the job, and it gives me a little more usable storage space than the un-hacked driver's side bin.

As for the durability of the SEM paint, everything is holding up great after about a year and a half - no chipping, fade or any other issues. The only exception to this is the driver's side door sill trim, On the door sill trim, which is taking a beating getting abraded by a very TIGHT door seal, and my shoes getting in & out of the car. The paint is just scratching off wherever the seal rubs it when opening/closing the door, and where my feet typically hit it. I've tried refinishing that piece 2x so far, with no improvement, so I will need to get an actual black piece there.

Panels came out great Pete!
SEM paint is awesome sauce :icon_tup:

Looks really good, Pete!

For the sills, those shouldn't be too hard to find used. Or get the stock aluminum ones or the CF aftermarket ones. I got some of the CF ones ages ago and they look and hold up great.

Dale