Kellis

iTrader: (4)

Hey all,

My name is Kellis, I'm a 21 year old grad student from Cincinnati, Ohio. I'm current studying mechanical engineering 500 miles away from home at the University of Alabama, which is why I'll only be updating my thread quarterly, when I'm back on break. I'll give the TL;DR info to start with and then get into some more of the details later.

The Goal:

Somewhere along the line I decided a carburetor was a better option than the stock EFI setup. Questionable, I know, but I've made my choice and have to stick with it now. The goal is to make modest N/A power with high revving capability on a very overbuilt engine. The rest of the systems in the car, like suspension, brakes, cooling, etc. have been or will be replaced or upgraded with the goal of creating a streetable car that will be at home on curvy mountain roads. It's going to be a long journey with limited time and money but I feel like I've made significant progress so far, enough to warrant a build thread at least.

The Starting Point:

I bought the car in July 2016. It's a red 90 GXL with 190,863 miles on the clock. When I bought it, the PO told me it hadn't run in 14 years, since the PPO (previous previous owner?) blew the engine. However the shell looked clean, with a full interior, little apparent rust, and a truckload of spare parts including some lightweight racing wheels, an extra 13b or two of engine spares, shocks, etc. So I bought it for a grand and trailered it home. After a good scrub outside and cleaning an entire poodle's worth of dog hair out of the carpets, it looked like this:




The Comeback

The first step was to identify the issue with the engine. After pressure washing everything in the bay, my dad and I pulled the block and transmission out and I started tearing the engine apart. It quickly became apparent why the car wouldn't start: one or more of the rear apex seals had vaporized, junking the housing and precious S5 N/A rotor in the process. Fortunately I had enough spares for a rebuild, which I bolted together in December 2016. I'll list the full build specs below, but essentially it's a half bridge with 6 port end plates and a TII center iron. Not sure what I was thinking there...



During the fall I had picked up a 45 DCOE carburetor from a guy here on the forums. While this is barely enough carb for a 13B on stock ports, it was a good price and would be good enough to run the car as long as I kept the 5/6th ports closed. The plan is to pick up a 48 IDA at some point, but there are a few other things to take care of first. Anyway, the carb was a little crusty so I "rebuilt' it, which basically just means a good cleaning a new gaskets.



I installed this, along with a an RB upper manifold, GSL electric dizzy, and some MSD coils wired up for direct fire. Additionally, I replaced the dead stock fuel pump with a Walbro 255 wired on a dedicated relay circuit, and added a Mallory return style regulator to bring the fuel pressure down to carb friendly levels. With all this in place, the bay looked something like this:



That was all done during the summer of 2017. In August, I fired up the car for the first time. There's a video somewhere, but the internet at home is too slow to upload at the moment. I got it to hold a steady "idle" around 2000 RPM, but couldn't get it to go lower. I suspected a vacuum leak, so I took apart the manifold and cleaned all of the mating surfaces, then carefully put it all together again. Unfortunately I had to leave for school before I could start it again, so I put some oil into the spark plug holes, cranked it a few times by hand, and sealed it up until next time.

Over the last winter break, I ended up overhauling the entire brake system on the car. I replaced the calipers, rotors, pads, master cylinder, flex lines, and rebent all new hardlines to replace the suspiciously crusty ones that were on the car. That's definitely not a job I want to repeat again, but at least now I'm less likely to blow a line somewhere down the road.



That about brings us to what I came back to after the spring semester ended. I should be posting again soon, with updates on the cooling system, exhaust, and ignition. But in the mean time, here's one last picture and an exhaustive list of the parts I've replaced to date.



Parts List:

Engine:

• 6 port front and rear plates, secondaries and aux ports bridged (questionable decision by the old me)
• TII center plate, street ported
• N/A housings, street ported with sleeves removed
• S4 9.4:1 rotors, matching weights
• RB 90 PSI oil pressure reg
• Stock lower manifold
• RB DCOE upper manifold
• Stu Kelly SS oil cooler lines
• Himni engine and trans mounts

Fuel and Ignition:

• Walbro 255 fuel pump on battery-fed relay circuit
• MSD 3-15 psi return style pressure regulator
• Replaced OEM fuel filter
• Weber 45 DCOE carburetor
• GSL-SE electric distributor
• MSD coils with HEI ignitors (DLIDFIS setup)

Brakes:

• Reman'd front and rear calipers
• New rotors
• Hawk HPS pads
• New OEM master cylinder
• SS flex lines
• New hardlines

Cooling:

• See next update

Exhaust:

• See next update

Suspension:

• Untouched currently, it's next on the list...

Misc:

• A/C and P/S deleted (heat retained for defogging)
• S4 manual seatbelt conversion
• Autometer water temp gauge
• 3D printed A/C vent gauge pod and single DIN radio bezel from a guy named Josh on FB
• More things I'm forgetting...

That's it for now. Thanks for reading!

mazdaverx713b

iTrader: (91)

Well done on the build! The car does look fantastic and exceptionally clean for the mileage!! You're definitely doing a great job on the build and I'll be looking forward to more updates!

Kellis

iTrader: (4)

Thanks, I appreciate it. Unfortunately it's not quite as clean as it looks in the pictures -- after working on it for a while I've discovered quite a few rust spots, including a couple bad ones under the rocker panels. After I get out of school I'd like to strip it down completely and dunk the chassis in an acid bath, then give it a much needed new coat of paint and undercoat. Some day...

As promised, I have some updates from the past week or so. A bunch of parts for the cooling system came in: Koyo radiator, new water pump, new thermostat, an aluminum thermostat housing, OEM rad hoses, Himni Racing water pump hardware, and a Racing Beat main pulley because we were having a hell of a time trying to read the timing marks off the 30 year old stock pulley. All of those went in without too much of a fight; the only issue was I had to grind down part of the water pump housing since I had rebuilt the engine with an S4 front cover and pump housing, then switched to an S5 housing I had cleaned up and painted. Pics of all that below.



New Koyo rad has to be twice as thick as the OEM unit...



New parts, plus the radiator brackets I cleaned off and repainted. Water pump painted as well, just used a cast iron color.



Cooling stuff installed. I'm very into the cast iron/aluminum colors right now, so that's what I've been painting everything lately. The RB pulley is slightly smaller than the OEM unit so I have to find some new V-belts to fit it.

Next up the ignition needed redone so the trailing plugs would work. I welded up a new coil bracket to hold the three MSD coils and ignitors I'd need for that job, shown below:



Bracket itself.



Bracket with coils and ignitors wired up.

Also had to gut a dead J109 (FB ignitor that mounts to the distributor) to pass the signal from the dizzy pickups to the HEI ignitors. This is the best/most secure method to connect the two parts.



With all that put on, the engine bay is starting to look a little busy. Might have to redo the wiring once I make sure it all works...



Finally, I had ordered a Racing Beat dual presilencer as well as one of their 2.5" universal mufflers to go with the RB header that I already had. The plan was to bolt up the presilencer, then have an exhaust shop fab up dual runners coming off that, collected somewhere near the rear axle, then out to the muffler. After some discussion with other people using a carbed setup, this seems to be a good setup for the modest power goals I'm looking for, without being stupid loud. The dual 2" OD runners of the RB header/presilencer have a slightly smaller combined flow area than the 2.5" ID muffler, so it shouldn't be a restriction.

However, disaster struck when I went to bolt the presilencer on. After an hour of pushing and shoving the presilencer around to try to get it to mate up to the header, it looked like this:



After talking with the guys at RB, I'm pretty sure I have a 1st gen header. It came with the pile of parts when I bought the car, so I assumed it was made for the FC, but apparently not. Regardless this was the excuse I needed to order a stainless header from them, which I did. It should come in Friday, but unfortunately I have to go back to school on Thursday. Kind of a bummer as I was hoping to start it up again before leaving, but oh well...

Still, I plan to make some progress on the car while I'm gone. The machine shop at school has a water jet that they'll cut stuff on without asking any questions, so I might draw up a fan shroud to use with an e-fan and have them cut that out. It'd be 2D but if I designed it right I could fold it into the right shape with the brake in our garage. Could be a fun project.

Again, thanks for reading! I'll be back in August, hopefully with a stockpile of suspension parts ready to be put on the car.

Jager

iTrader: (10)

I really like it!

I honestly have nothing against carbed setups and have seen them make more power and with enough time, decent drivability (not to start THAT discussion).

How does it drive with the aux bridgeport?

dhill

Great build. I'm leaning towards carb for my build, but I'm still gathering info on the topic. Wish u the best on your build.

Kellis

iTrader: (4)

Thanks for the kind words! Not sure how it runs/drives with the aux ports open, it's only been run a few times and I just left them closed (sleeves still in at this point). Hopefully will know more when I'm back again in August.

Thanks. If you do decide to go carb, I'd recommend you start off the bat with a 48 IDA. EMPI makes a good Weber clone for like $379, the casting is supposed to be just as good as the real deal and all of the parts and jets are interchangeable with Weber spares. They also make a 51 IDA for $500 something.

dhill

I'm looking at the Weber 48 IDA. With a street port. I know nothing about jetting carbs, but it will be a great learning experience. Are you gonna track it?

Kellis

iTrader: (4)

Sorry for the delayed response, was waiting for something relevant to post about. I'm hoping to do some form of "racing" with it eventually, once the carb situation is figured out and I get some suspension work done. The hard part will be finding a class I meet the restrictions for but won't be terribly outgunned in.

Anyway, as promised, here is the update for the third quarter of 2018. During the summer I slowly accumlated a small pile of parts including:

• RB stainless header
• AEM wideband
• Auto Meter water temp gauge
• EFI hardware IDA manifold

The header bolted on with no fuss, thankfully. Plus it looks much better than the old rusty thing I had on before:


Then the wideband and water temp gauge were installed into the 3 gauge pod I bought from a guy named Joshua. Both went in fine, no pics there though. I'm debating whether to fill the last spot with oil temp or pressure. Both are important but the OEM pressure gauge still "works"... as well as it ever did at least.

Tuesday I went to check for spark before starting and was dismayed when only the trailing plugs were firing. After some investigation it seems both leading ignitors were burnt out. I'm guessing they overheated since they were only attached to a small aluminum sheet. Grudgingly I made a trip to Autozone to get new ones, and mounted them on a thicker piece of steel bar stock bolted to the strut tower. Hopefully they last longer that way.

Yesterday, my buddy came over to hang out and see if we could get the old girl going. He arrived in his FRS and suddenly we had a small car meet in the driveway:



Spark checked out on both sets of plugs this time, so we moved on to fuel. However disaster struck again when gas started spewing uncontrollably out of every orifice of the pressure regulator... I hate NPT threads. After taking out all the fittings, recoating with thread sealant, and some verbal abuse, the leak was contained (for now).

However, running the fuel pump for longer than 10 seconds or so produced a peculiar reaction... when the bowl filled, gas would begin to spray out of the main jets, pool up in the barrels and eventually run out of the velocity stacks onto the engine. The pressure gauge reads 3.5 PSI after the regulator, and I thought I set the float level right when I rebuilt the carb, but apparently not. Will have to dig into it tomorrow before I get immolated and/or burn down the garage.

Still we pressed on. After drying up the excess gas and recruiting my dad for some help, we gathered up 3 fire extinguishers and began cranking the car. It fired up without too much fuss, and by keeping an eye on the barrels and modulating power to the fuel pump, we were able to keep it running with a lumpy but steady 1000 RPM idle. It sounds somewhere between a tractor, a lumpy V8 and a rotary. I think it is idling way rich but I will have to sort out the fuel fountain before making any adjustments. My friend, being a Mustang guy, was quite concerned by this point after being sprayed with gas and nearly choked out by the oil smoke from the startup. Judging by his face I doubt he'll be coming back:



So now I have my work cut out: stop the fuel from coming out the intake. Tomorrow I'm going to try lowering the fuel pressure and float level. Then I can finally get to work on tuning the idle circuit. However if that doesn't work I might be forced to bite the bullet and buy an IDA earlier than anticipated. This DCOE scares me sometimes... and I did preemptively purchase an Aussie style IDA manifold, which is a good chunk of the cost anyway.

I think that covers everything. If you're reading this please send a prayer to the patron saint of firefighters that I don't get crisped. I would greatly appreciate it!

Kellis

iTrader: (4)

Hey guys,

As scheduled, here is the winter quarter update. Last time I left off, the car was having some issues spewing fuel out of the jets if the fuel pump was left on. Fortunately I was able to cure this just by turning the fuel pressure down, so it wasn't a big deal. However, the next day when we tried to get the car started again, it was pretty much impossible. After we got the timing light out we realized the rear leading coil wasn't firing, and its ignitor was extremely hot to the touch. I'm guessing they weren't heat sunk well enough and burnt out. That was the second one I had gone through, and I really didn't want to drill holes in the chassis to bolt them to the strut tower or something, so I decided to go back to the OEM coils using...



A Megasquirt 2. I ordered the kit from DIY Auto Tune and put it together in a day. Everything went smooth, at least I thought. The voltages in the CPU socket checked out, and it passed the loopback test, but for some reason no computer I tried would recognize that the Megasquirt was connected. I sent the daughter card back for Matt at DIY to check, and it seemed OK. After some more troubleshooting I sent it off to Jeff Linfert, who I had been refered to by Matt. He spent a lot of time on it, swapping out multiple components, before reaching the conclusion that I had probably burnt out one of the traces using too much heat with the soldering iron. Rather than try to find which trace it was, which would probably end up costing more in the long run, he and I decided it would be best just to start fresh. So he's building a board for me with dual VR inputs, and 4 of the newer MOSFET style spark outputs which won't burn out the coils like the LED method on AaronCake's writeup. With 4 outputs I can move to a COP setup in the future if I want, but can use the OEM coils in the meantime. I'm pretty pissed at myself for screwing up the board, but this way I end up with slightly better functionality and a 1-year warranty. Live and learn.

Anyway, the semester ended last week and I did pretty well, so I decided to buy myself some early Christmas presents. I got back home with the following sitting on my workbench:



A brand new Weber 48 IDA , a 6-port IDA manifold, K&N air canister, Racing Beat heat shield, a bunch of jets, some AN hose and fittings to hook the carb up, a new Mazda 12A throttle cable (longer than the 13B version to reach the IDA), some sensors for the ECU, a vacuum resevoir for the power brakes, and some other small parts.

At this point you may be confused - I ordered a Megasquirt, but also a new carb? The plan is to run the MS ignition-only, to replace the distributed setup I had before. Even the DLIDFIS setup is a step back from the stock FC ignition, and I didn't want to mess with the stupid ignitors anymore. Plus the dizzy is pretty ugly to look at. The stock coils will clean up the engine bay a lot I think. The Weber will take care of providing the appropriate amounts of fuel and air, and should be big enough to flow what I need. I ordered some 40mm venturis to start with, but may move up to 42mm if the top end seems lacking.

While I am wiring the car for the ECU, I also plan on removing the shock tower fuse box and creating an equivalent fuse panel in the driver's bin, where the fuel, ignition, fan, and ECU relays will be, along with the ECU itself. This will require running new main, BTN, headlight, and retractor wires, which shouldn't be a big deal. I ordered all of the needed supplies from Tony at CE Auto Electric, who I highly recommend for any type of relay, connector, fuse panel, etc you could ever want for your car. Additionally, I'll be pulling the unneeded stock connectors out of the front harness to trim down the loom size.

Today I started pulling the interior out of the car to make wiring easier. While the dash is out I'm also going to clean up the wiring for the gauges, which are going to get power from the ECU relay circuit instead of the cigarette lighter like I had them done before. I got a few Molex connectors to make this clean, and am keeping updated wiring diagrams as I go to make troubleshooting easier if issues occur. Additionally, I'll have switches up front on the radio panel for the fuel pump, coil circuit, and gauge illumination, plus maybe a 4th in case I want to add a circuit later.

Well, that brings you to the current state. If you've made it this far, thanks for reading! I'll post again when I have something to show.

SirCygnus

iTrader: (1)

id go with haltech. Im surprised anyone at diyauto tune even looked at your board.

Kellis

iTrader: (4)

I originally went with the MS2 for the "fun" build aspect, which clearly didn't turn out as expected. Between the original cost for the MS2 and Stim, the fee from DIY to load the firmware, and the cost to have Jeff build a new one, I'm probably around the cost of a used Haltech or similar. So it goes...

Anyway, small update. Right now I have the whole front interior out: seats, dash, carpet, bins, etc. I was pleasantly surprised not to find any rust in the floor pan or interior of the rocker panels, I was sure there would be a few spots. I've finished routing the new wiring for the ECU and gauges and am working on wrapping the harness back up now.

I'm waiting on a firewall stud for the main 12V wire and oil pressure gauge to come in from Summit, then the inside will be ready for reassembly. Next up is port matching the new intake manifold and hooking up the new carb. If it stays warm out and the ECU gets done in time I'm hoping to drive it around before I go back to school. If anyone has a decent timing map for an N/A car beside the one on AaronCake's site, I'd love to see it.

Thanks,
Kellis

Kellis

iTrader: (4)

Hey guys,

Happy New Year, hopefully everyone else is getting as much done with their time off as I am. Wanted to post an update now to break up what would be a really long one if I waited any longer.

As I mentioned earlier, I had been doing a lot of rewiring to prepare for the Megasquirt, delete the engine bay fuse box, and fix some janky gauge wiring that I had done a few months ago in a hurry. All of that is done, and the fuse box has been moved to the driver's side rear bin as you can see here:



This fuse area includes circuits for the main ignition feed, BTN, headlights, retractors, heater, defroster, coils, fuel pump, ECU + gauges, and electric fan (a purchase I'll be making in the near future). It will get power via a short cable from the battery, conveniently located in the passenger bin. I also plan to mount the ECU here, on some risers above the wires in the bottom of the picture. Also, it's a good spot to put the stickers I've slowly been acquiring where I don't have to see them all the time.

By the end of the wiring, I was about ready to throw my soldering iron out the window and never work on the car again. With great relief I turned to work on the carb, which needed a few mods before I could put it on. First up was to install a Weber 300 needle jet and an AN fuel inlet:



For some reason, Weber doesn't set the float level from the factory. Following a guide I found online, I cobbled together a set of float tools to get that done. I will probably draw these up in Solidworks and have them waterjet cut when I am back at school, but for now these did the job:



With the float level set, I put in some 40mm venturis and a 195 main jet, leaving everything else stock for now. The idles are 70F10s, which might be a bit too big, but I didn't have anything smaller on hand. Related, does anyone know if the DCOE and IDA idle jets are compatible? Mazdatrix lists them separately but I don't see any visual differences. If they're the same I have a bunch from my DCOE to use.

The K&N fuel filter went on without any fuss. I was pretty disappointed to see that you can't get the jets out without taking the whole filter unit off, but other than that it's a quality piece. Here's a side by side of the old DCOE and the new IDA:



Side note, if anyone's looking for a decrepit 45 DCOE, let me know. I'll let mine go for cheap, but it has issues

The last thing on the list of carb-related stuff was to port match the manifold to match the larger TII runners. I just traced the gasket pattern onto the face and went to down with the grinder. While I was there I smoothed out the manifold as far in as I could reach the tool. Here's a before and after:



Finally, I stacked everything together just to get the picture. IMO this is the most visually satisfying rotary setup - and hopefully it will perform as well.



I'll be running a vacuum line from the two nipples on the manifold to a vacuum tank, I think. I doubt the power brakes would work very well without it, but if anyone has experience here I'd love to hear it.

Tomorrow I'm hopefully going to put the carb on the car. Then I can start looking at how to route the vacuum and fuel lines, as well as fabricate a new bracket for the throttle cable. Jeff Linfert finished my ECU today and is shipping it out tomorrow, so hopefully I'll have some time to play with that before I go back to school.

As always, thanks for reading! Advice, questions, and/or criticisms welcome.

chuyler1

iTrader: (1)

The brake booster doesn't need vacuum from both rotors, it will work fine with a large vacuum port from a single rotor. In fact, the pulsing may actually work better than a steady vacuum signal....or I'm just making that up. What I do know is that on the earlier motors the brake booster vacuum hose is separate and hooked up to the rear secondary port. I'm surprised that manifold doesn't have a bung for the booster on the back side. One other note, the booster hose does need a check valve somewhere in the system. Sometimes its within the short hose between the hardline and the booster, but if that hose has been replaced it may be missing.

Anyway, here's a suggestion. Use one of these vacuum manifolds. There are two 1/8" NPT threaded ports on the sides you can connect to your manifold. In the center is a large 3/8" NPT threaded port for a hose that will work for the brake booster. The remaining ports can be used for fuel pressure regulator (if necessary), ECU MAP sensor, and whatever else you want to connect.
https://vibrantperformance.com/catal...3fc8ccff806341

Kellis

iTrader: (4)

Glad to know it will work off just 1 rotor. I was thinking I'd have to rethink my plans anyway, since the vacuum tanks come with a check valve on the inlet, and I couldn't put the MAP port there for that reason. The manifold does have a big boss on the back of the rear runner, I may tap that for a big fitting like you suggested. Then I could just run the MAP line off the pre-tapped fittings on the runners, eliminating the need for the tank or the Vibrant manifold you linked.

Regarding the MAP, do you know if it can be run off just 1 rotor, or should it be hooked up to both? 1 connection would be easy, could probably hook both up with just a tee fitting.

Thanks!

EDIT: Do you know if a standard replacement hose from AutoZone or similar will come with the check valve installed? I think my stock one is long gone.

chuyler1

iTrader: (1)

Yup, that one on the back of the manifold is specifically for the brake booster. Your map sensor will need a signal from both rotors so a T with equal length hoses will work fine. I don't know if the replacement hose will have the check valve but the parts store should have something you can splice in-line.

scathcart

Kellis

iTrader: (4)

Thanks man! I'm glad I can ditch the whole tank setup. I tapped the rear boss today for the booster fitting, looks like it'll line up with the stock hardline with just a few inches of vacuum hose. I'll check the parts store for the tee and check valve tomorrow.

Cheers,
Kellis

diabolical1

iTrader: (3)

I really like this. It's a really cool project and it's also a great way to deal with the rigors of school. I have been seduced by fuel injection, but I have enough skin in the carburetor-game to be able to appreciate them for what they are AND appreciate when someone commits to trying to do it right. I wish you the best with your road ahead and I will definitely be following you and your project. If I can help along the way, I will.

Kellis

iTrader: (4)

Thanks, I appreciate it! It may have been a little half-assed at first, and I would definitely change a few things if I could go back (use Turbo II end plates instead of 6 port). I think it's starting to shape up though. Almost all the engine-related stuff is done, and after I set aside some money to finish up the exhaust, it'll be time for a suspension overhaul. Woohoo!

I've heard yes and no on the check valve. I'm going to use one, to be safe. Imagine you're on a long straightaway of country road, in the middle of a WOT pull, and a deer jumps out at you. Without a check valve, your booster has had time to equalize with the manifold pressure; i.e., it's at atmospheric pressure because your throttle was wide open. You slam on the brakes (or pump if you're a ninja), but basically have no assist because your booster isn't in vacuum. You might argue that as soon as you let off the throttle it instantly re-enters vacuum, which could very well be the case. However it's a $5 part so might as well use it for some cheap insurance.

Disclaimer: the above anecdote is just something I thought through and seems to make sense to me. If it's BS feel free to call me out.

chuyler1

iTrader: (1)

Mazda (and most other manufacturers) put one in the hose from the factory in all vehicles, even pre-dating the turbo models. Although most brake boosters have an internal check valve, the external one serves as a redundancy as well as a way to prevent any air/fuel mixture from the manifold from seeping into the booster. It's location is strategic, at the high point of the hardline going to the booster. When you turn off the car, fuel has a tendency to evaporate and rise before it condenses. If fuel were to make it into the booster hardline and condense, and you were parked at a slight angle, it could dribble into the brake booster hose and collect near the internal check valve. The next time you tap the brakes some of it could dribble into the booster. Over time, it would eat away at the rubber diaphragm. With the additional check valve at the high point of the line, all condensed fuel or moisture must travel back down to the intake manifold when the car is off. That is also the reason why you want the booster line connected to that low rear port on the intake manifold.

Kellis

iTrader: (4)

Chuyler - ah, there it is. Thanks for the explanation.

So in the last few days I did some electrical work, installed the carb, did some troubleshooting, and cleaned up a few other loose ends before it was time to head back to school.

First up, I had to install the carburetor and manifold. This went smoothly, except for that the canister filter didn't clear the hood, even without the phenolic spacers on the intake. With just the carb and manifold, there is slightly less than 1/2" clearance between the velocity stacks and the hood support. If I cut out the support, I'd get an extra inch, so enough to run the spacers but not the K&N filter. I bought some new JayCee stack filters off a guy on FaceBook to cure the issue for now, but I'll probably end up cutting the hood support later to gain extra space. It was suggested that I just cut a hole in the hood and run the filter out Mad Mike style, but that seems a little extreme. Other than the filter issue, everything else went fine. Brake booster and MAP lines hooked up, everything is ready to go.



After that, it was time to solder the DB37 connector. I try not to hate specific jobs when working on the car; after all, hobbies are supposed to be fun. But there was no escaping it - this job sucked *****. If anyone reading this is considering skipping out on buying the DIY AutoTune (or similar) premade harness, save your sanity and cough up the cash! Grudgingly I set up my soldering station in the bin area. By the end of this job my knees were about locked up and I almost fell over getting out of the car.



But, I think the fuse / ECU panel turned out pretty good. A friend and I tested out all the circuits today. The ECU clicks on when the key goes to IGN1, and then the fuel pump and coil circuits can be flipped on by switches in the center console when the key is on. The headlights, retractors, and the BTN and main circuits all work as well. For some reason the heater doesn't work, but it hasn't since I've had the car. I can hear it clicking under the dash when I push the slider on the logicon, but nothing happens. I'll fix it another day.



Another add-on: after the incident with gas spewing out of the intake my dad decided to gift me a fire extinguisher. He's an aircraft mechanic and they apparently have a bunch of spare mini ones at work that people put on their private planes. So he got me one and I put it on top of the passenger bin lid, where I can reach it if necessary. Also it adds horsepower, right?



That about concludes what I've got done over break. I started to try setting up the tune today but most all of the setting screens have changed since Aaroncake did his write-up, so I'm going to have to sit down and go through the newer documentation to figure out what settings I need. I have an MSQ file saved so I can work on the tune off-line.

Another project I have in mind is to redesign the center console area where the stock radio went. Originally I was going to put in a single DIN unit and bought a bezel from a guy who 3D prints them. However I think I've decided against putting a radio in at all. Instead I'd like to put a small LCD screen which can display various engine parameters which I don't have gauges for. I'm particularly interested in oil temp and fuel pressure, but if I wire up an Arduino or similar I could monitor practically anything. Then either time it to scroll through them every so often or have a button to switch between the data. Here's an interior pic to show the area I'm considering:



I took the cigarette lighter metal trim piece out because it was absolutely nasty. It's in my bucket of parts to have powder coated when I get the chance.

Other than that, finishing the exhaust and starting the suspension overhaul are next on the to-do list. I plan on setting aside some money at the start of the semester to finish the custom exhaust I had planned, then coilovers would be the next big purchase. After those, I'd like to drop the front subframe, put in a reman steering rack, all new front bushings and ball joints, powdercoat the steel parts, new bearings, etc. to get a feel for the suspension work. Then after that, do the same for the more complicated rear suspension.

I am graduating in May, and might be getting a real job soon after that. If everything goes to plan I should have more money to spend on the car in the second half of the year, which is pretty exciting! If I don't post for a while it's because finishing my degree and becoming an official adult took priority for a few months, but I won't give up the project.

Thanks guys

Jager

iTrader: (10)

Awesome! Let us know how it works!

newbrap

Hope you finish the school year strong, I have probably another 2 or more years to go. Have any ideas on what suspension you want to run?

Kellis

iTrader: (4)

Thanks! Will do.

I'm trying, good luck to you as well. I think the "first stage" of the suspension upgrade will be pretty standard. Replace all the wear items (bushings, ball joints, powder coat rusty stuff), then go with basic coilovers on all four corners. Either Fortune Auto, which have decent reviews, or BC Racing since one of my buddies is a dealer and gets a good discount. That way it stays simple and I can actually log some miles on the car. After that I'll have to figure out which direction I want to head, be it autocross, track events, or just keep it as a normal street car. If I do decide to do some track stuff I may take some inspiration from this neat Bilstein thread:

https://www.rx7club.com/suspension-w...thread-955929/

Kellis

iTrader: (4)

New post time. First off, since it's the most important, I'm looking for some advice. When I was jacking the car up to put the exhaust on yesterday, I noticed this:



Besides the ultra-crusty LCA's, the return line seems to be leaking/seeping right above the rear subframe. ****.

After some browsing on this forum and others, it seems like i have two options to deal with this. The first would be to drop the subframe, take out the old lines, and bend new ones to match them. That seems straight forward enough, but I know if I drop the subframe I'll want to refresh everything on it. While this would be money well spent, and it would make the fuel lines much easier to do, I was hoping to actually be able to drive the car this summer, and another expensive project will probably keep that from happening.

Option 2 is to rip the old lines out, and bend new hard lines back just to the point where they cross over the subframe. From there I could run soft lines up to the fuel pump. While this would be an easier and quicker job, I'm not sure how well soft lines will last in the under-car environment. I could do braided hoses and AN fittings, but that's more money that might be better spent elsewhere.

So, between these two, what do y'all think is the best route?

A brief life update: my advisor convinced me to stay for a PhD, so I'll be in school another 2-3 years. This means the quarterly updates will maintain their frequency for at least that long!

In other news, I came home for the 4th to do a little work on the car and see my family in my spare time I got some more parts installed, with the highlights including a FFE trigger wheel kit, Flex-A-Lite e-fan, RB oil pedestal adapter, and some other random things. At this point, I'm going to try to stop spending money on the engine bay, as I think it's in pretty good shape. The exception being I need to make/purchase some radiator ducting panels, and figure out what I'm going to do about the IDA filter situation. I have some JayCee air horn filters on now, but I don't think they flow or filter very well. Here's what the bay looks like as of today:



Like I alluded to above, I've got the exhaust system worked out as well. I ended up just going with a dual system. I already had the RB header and presilencer, so I went ahead and bought the Y-pipe, and their muffler extension tubes to mate with some aftermarket mufflers that came with the car. While I probably will get the RB mufflers eventually, the mufflers I do have are in good shape, so might as well try them out.

So next up on the to-do list is to redo the fuel hardlines. I'll probably go up to 3/8", which shouldn't be a big deal since I'll only have to change the connections to the fuel tank itself. The FPR will just need new barb fittings, or I can run AN straight off the hardline. I was hoping to drive it around after I put the exhaust on, but if this turns into another big project, that might not happen til next year.

One last question I had - the hardline running between the gas tank and charcoal canister is still in place, terminating right under my FPR. I don't plan on re-installing the canister or EVAP system, unless there's good reason to (feel free to chime in), so I'm wondering what to do with the line. Cap it, and leave it in place? Or discard it completely when I have all the lines out? I'm leaning towards discarding it and capping the fitting on the tank, but please let me know if that's a bad idea!

I think that's all for now. Any advice on the fuel line situation would be appreciated!