SETaylor

iTrader: (4)

Hi folks, figured I would create a thread cataloging my experiences in dismantling, assembling, and modifying these four-wheeled wonders that we know as third generation RX-7s.
First, I would like to provide a little background information on how I found myself in this wonderful position (predicament!).

I stumbled across this forum by happenstance back in 2017 and was not particularly interested in cars, but had also just discovered FIA GT and IMSA at the time and had just decided that I wanted to pursue a career in engineering. After perusing the various how-to's and general discussions here, I came across many rather exhaustive build threads and development efforts posted by the dedicated members of this forum, I had made up my mind: I wanted an RX-7. One problem, I didn't have a job (or the requisite capital to procure such a vehicle) and wouldn't for the next two years. But reading every thread I could find here cost me nothing but my time, so I did just that. I spent the next two years reading and consuming every piece of RX-7 related material I could find when not doing schoolwork or playing hockey.

Fast forward to graduation, I got a full-time job working nights and attended college classes during the day. I started saving all of the money I made since I had very little if any living expenses and figured I would buy myself a very nice spirit R with some obscenely low number of miles for $30k by the time I graduated from college and got a job as an F/A-18D Weapons Systems Officer making big naval aviator bucks whilst hoarding RHD FDs while stationed in Japan (Did not necessarily go as planned since the Marine corps closed off accession to that MOS, so I reclassified to Judge advocate, I just need to get my butt to OCS and law school)
Well, like many other things in life, my plan did not go as expected. During the summer of 2020, I noticed that it was getting much more difficult to find "nice" third gens for sale, and the ones that were on the market were rather spendy. so I figured that I ought to get one before I ended up missing the boat. This was also when college courses transitioned online, so I took my courses elsewhere. At the office I was doing my schoolwork at, I noticed that there was a '94 CW parked at the end of the lot. I had seen the car once before going down the highway, once before and thought that it was the first and last time I would see it. I left a note on the door handle explaining my fanaticism about the platform and explained that I was going to be in the market soon and wanted insight regarding ownership and maintenance and left my email address.

Miraculously, I got an email a day later with his phone number, and I later went for a spin in the aforementioned vehicle, powered by a large street port REW with an S362SXE bolted to the side. It was rather wild. The next day he brought his '93 VR base that was running stock twins, and we rode in that. Turns out, this crazy old guy (aarkaah) had owned several of every generation of RX-7 dating back to 1985 or thereabout, and lived right up the road from me.
He didn't have anyone to help him work on his cars, so I willingly volunteered and was able to gain a lot of experience in not breaking interior plastics whilst attempting to remove them, general maintenance, and other things that you would do to an FD.

Then came May of '21. I had all of my funds read to go, I just needed a car to spend it on! This was right about the time the gentleman mentioned above was looking for a chassis to use for his single turbo three rotor build. He found one of the four produced automatic 1994 Silver Stone Metallic base model in Illinois, right out of Chicago. The seller was an older gentleman who had owned the car since 2005 and had allegedly only put 1000 miles in that time. When asked about the condition, he replied that it was a "cream puff" that was in the greatest condition that you would ever see, so he flew up there ready to make the purchase. Without going into too much detail, the car was NOT a "cream puff" as previously alleged and was going to need some work. He gave me a call and asked me if I'd be interested. I had read up on the manual conversion and was rather apprehensive about it, being that I had never done anything of that scope, but I knew that it would likely be my last chance to procure one for as little as it was, so I gave the okay. Made it all the way down here without a hitch!

I put a few miles on it and encountered my first (expected) issue, which was signs of impending water seal failure!

aarkaah drove it back all the way from Illinois to eastern PA in a couple days, and I had a SSM hardtop with 51,109 miles on the odometer (had to send cluster out for repair to find that out).

Here is one of the first photos I took of it, bug parts and all!

The car wasn't perfect but it was a good foundation to do whatever the heck I wanted with it. It also came with a ton of parts that I subsequently sold to fund the purchase of a new engine, GReddy v-mount, and all of the requisite parts to do the manual conversion.

After taking inventory of everything and determining what parts and materials would be needed to do the work, we began disassembly. This thing was FILTHY! for whatever reason, the shop (a well-known one) that was hired to do maintenance on it vented oil vapor directly into the engine bay. I had to spend three days cleaning the thing because every square inch of the bay was caked in grease, and so were all of the peripherals on the engine. I spent an entire month cleaning it all with an old toothbrush, brake cleaner, and low odor mineral spirits in my garage.

I won't bore you with the minute details of the conversion, but will say that it actually was not that bad, just annoying. I'd do it again if I were ever in another position to obtain and properly maintain another third gen.

After months of waiting for a few specific parts to show up, we got it running.


Before

Maiden voyage
Do note that for whatever reason, the previous owner swapped the tan seats from the Montego blue car that he also owned at some point into this silver car (still a little upset about that )
If anyone here has a '94 MB JM1FD3336R0300984, I've got your seats and original purchase receipts, and some service records!

I brought my car back to my garage on November 7th

I later put the hood and headlight covers on. Drove when the weather permitted to get break-in miles and learned the car. and assisted on the single turbo three rotor build for the next several months until we got that running.
Put a couple thousand miles on it until I ran into a little issue.

I would smell coolant intermittently. I thought I was just imagining things until I actually saw it coming from under the glovebox, and concluded that I had a leaking heater core. ( I didn't but I would not know this for several months until I was able to get the dash out to have the carpet sanitized. Turned out to be a direct result of me bending a coolant pipe!)

I looped the heater core and ran without heat for a while until I was ready to take the thing apart. Everything worked as expected.
Began disassembly on the car and noticed that I had some torn-up insulation and something that resembled mouse droppings. While less than ideal, I figured it was confined to a single area.

Turns out I was wrong! this thing was literally full of crap! I ended up having to pretty much junk all of the jute padding that was in the car. (Will provide photos of the carnage in a later post)
I had poop everywhere and it was stuck to the floor pan. I spent several weekends when I was back home from school steam cleaning and sanitizing the thing. I thought I was done, and I realized that I never checked the headliner. So I began removing it and heard a bunch of stuff moving around up there. Got it down and it began to rain mouse droppings all over myself and my newly sanitized floor. I was less than thrilled with this discovery. and had to clean everything all over again.

By some divine measure, the mice that once resided in my car were not interested in my wiring, so you would think that all would be well, correct?
This was not the case. The previous owner had some aftermarket electronics installed in the car, and whoever he paid great sums of money to perform the installation absolutely butchered parts of my chassis, just about every wire harness in the car and some other difficult to find parts.

Will provide photos later. I want you all to see just how poorly this stuff was installed. I had a head unit connector that was partially melted together!

Prior to this, I had always been interested in building a track car and competing in time trials and SCCA/PHA hill climbs, but told myself that I could never do it because my example was too nice to do so. After getting to experience a single turbo FD for a few (slow) laps at Pocono Raceway, I was hooked and said to hell with it, I really only ever drive the car to aarkaah's house and the gas station, and with all of the horrendous drivers I have the pleasure of dealing with on a daily basis by virtue of being so close to NJ and NY and knowing that sooner or later I may be liable to have it written off due to that, I may as well go build the car I always wanted, because I am only going to get one chance in this game that we call life.

This brings us to the present day. I am now preparing the vehicle for some fabrication and safety equipment (someone let water get in the hatch and I have a hole in the spare tire well)
Pulled the front ring harness and am currently mocking up a new harness for the impending PDM installation.
Also working out a single turbo conversion, given that I already have most of the expensive parts required to do so.

Whilst I know dismantling a vehicle to this extent with such ambitious plans often results in failure, I am dumb enough to attempt to do so and expect that my outcome will be different.
Stay tuned!
more pictures to come off the butchered harnesses, chassis and botched sound system install and mouse poop mountain!

DaleClark

iTrader: (55)

Nice, looking forward to more posts on this one!

Dale

Molotovman

iTrader: (49)

Thanks for sharing. I especially enjoyed the park about how you met Ato!

gracer7-rx7

iTrader: (16)

I remember @Aarkaah
Let's see if we can drag him into this thread

Aarkaah

iTrader: (5)

Damn tagged in a thread!!!! Can’t ignore it now. 😂

Seriously though @SETaylor has put in some serious work on this car post the rebuild and upgrades. Once he puts the car back together it will be beautiful.

What really got me on this car was that despite my best efforts there was no way to determine what was going on behind the scenes. Let this be a caution to “barn yard” shoppers. You get what you pay for and then some!

Anyway Simon and I have worked together in my garage on 3 other cars since then. The last one, my blue Mazdaspeed 20B, goes for tuning next month!!!

Following your thread Simon!!! Let’s go!!

SETaylor

iTrader: (4)

As promised, here are an assortment of photos taken over the course of the disassembly process.


alleged high dollar head unit installation. Had to have been at least eight feet of wire jammed in there.

Hole in spare tire well+ botched stereo installation.


Mouse poop floor pan!

Mouse poop headliner!

How not to install a keyless entry system. put a hole in the chassis to pass wires, and also jacked up the X-20 connector.

Twist and tape in place of crimp and heatshrink.

Current state of vehicle.

Passenger side headlight

mocked up harness on passenger side.

Mocked up harness on driver side.

Mocked up harness routing for headlight.

a few of the wires that will be going to the charging harness.

Will post photos of my revised front harness schematic, Picked up a pre-owned but never used E-T-A SCS-3000 (pretty much a Syvecs/ Life Racing PDUx2) from the United Kingdom.

Aarkaah

iTrader: (5)

That car didn’t leave my garage like that! Lol. I hope everything is labeled man.

ZumSpeedRX-7

iTrader: (12)

Great stuff Simon - looking forward to this coming together


I had looked into a Syvecs system as well, and found (as you most likely did too) there aren't too many FD's running one. Solid cop out on my part in going with an Elite 2500 (many more use cases to go off of in joining this century from my trusty Power FC)

That all said, Eric (@speedjunkie) was one of the only FD owners I was able to find with a Syvecs (Life?), and was an awesome help in sharing pain points/precautions/whys and why nots and his findings with me

There's also a tuner that used to be local to me, Franz Diebold, who had experience and gave me great feedback on either Syvecs/Life that may come in handy for you. He used to dial into our endurance S2000 MoTec trackside, and had sorted out many a pre-green flag mess for us. I can ping him to set up something for you if you'd like

Edit: no informal hand off needed - Franz has his own site here


Best of luck!

SETaylor

iTrader: (4)

With enough plastic bags, tape, and factory service and wiring manuals, you can do anything!

Additionally, here are some photos of the work Aarkaah and I did over the summer when we performed the engine replacement and manual conversion.


Australian style engine pull.

New short block prior to installation of peripherals and sequential system.

All vacuum lines redone, courtesy of Aarkaah himself!

About halfway through the process, my family went on vacation and took me with them (against my will) leaving Aarkaah to put all of the vacuum lines together. Everything worked as it should!

SETaylor

iTrader: (4)

Thanks for the recommendations! I'll likely end up reaching out to them at some point in the future.

I really like how open-ended the software is and the fact that just about everything is user-programmable. All of the other features are nice too. A 2500 would have been sufficient for my purposes, but I like the syvecs/life architecture better
I had an old Autronic SM4 that I pulled off of another FD that I could theoretically use, but I don't think anyone in the rotary world programs those anymore and it doesn't support CANBUS. I could probably get it to work, just likely not the way I would want it to.

speedjunkie

iTrader: (3)

Indeed. The Syvecs is a great ECU, and it probably saved my butt numerous times, but it was too confusing for me and being one of maybe four people in the country using it meant information for simple fixes wasn't available, which meant I had to run to Chris every time I needed help with even the simple stuff. Not to mention he's one of only four shops in the US authorized to tune it, and he's the only one that does rotaries also. Chris was super helpful though, and still is.

Looks like this will be a fun build! Congrats on the purchase, Simon!

DaleClark

iTrader: (55)

Yeah skip the Autronic, had a guy running that here, he had ZERO support on it. Also I think it really didn't do trailing timing right, like you just set a fixed split and that was it.

PFC has new legs after the amazing FC-Tweak came out that can autotune for you. Haltech is great but it's still not as simple of a plug and play process as the PFC.

BTW it looks like they took the hump out of the bottom of the spare tire well that the spare mounts to, most likely to make it flat so they could put a sub box or something in there. Yeah car stereos are nice but damn don't go cutting off the damn CHASSIS of the car!

Dale

Molotovman

iTrader: (49)

If it was an SSM on red car it could be the same Autronic ecu.... :P

SETaylor

iTrader: (4)

Previously, I had been planning on using the post(s) that the spare tire would mount to affix a battery mount to. I was less than thrilled when I peeled back the dynamat to find that someone had cut the post out and bashed it in with a hammer. Quite truthfully, I don't even think the previous owner was aware of that, since he hired a stereo shop to do the work.

I'll be addressing it (properly) sometime this year!

SETaylor

iTrader: (4)

PDU/PDM showed up today. It's a 16 channel unit, and I am going to need more to provide power to everything that I would like. I decided to use two units for better packaging when installed in the vehicle. I'll probably affix one to where the ABS computer is and the other to a mounting plate on the firewall that I will have fabricated after I throw some Cardboard Aided Design at it




E-T-A SCS 3000-16.

SETaylor

iTrader: (4)

Front harness schematic has been finalized. Now to determine the current values that will be running through each wire so I can size accordingly.

My very primitive schematic for the revised front harness.

Molotovman

iTrader: (49)

@SETaylor Just a word to affirm your plans before you go too deep. You're approaching a point where it's hard to turn back from which is the "semi-custom race car" point. Outside of the mouse nests it appears that it was a clean example with no body damage which is increasingly harder to find.

I encourage you to keep this one mostly stock and mod another one that is less nice.

SETaylor

iTrader: (4)

Yes, I am aware that I am at the metaphorical "point of no return". I struggled with the whole "do I leave it alone because I can get more money for it, or do I go build what I want and enjoy it?" dilemma for the longest time. Quite truthfully, if I knew that I would end up going this far, I probably would have looked for something less nice, though it probably would have cost me the same amount of money or more given how little I paid for my chassis all things considered (at the time). I also have a few rust holes in the trunk and also had some metal cut out of there and beat down with a hammer to fit a speaker box. The only real way to fix that is to cut out the section and have a new one welded back in, Previous owner also went wild with self-taps, so I have several of those to have plugged. The dash harness also had a ton of extraneous stuff poorly spliced into it, hence why I am opting to control body functions with a PDM, given that there are far fewer wires and all that needs to be done is for me to construct a harness and program it. Could I have just replaced the harnesses with some that were unmolested? Yes, I could have, but for my purposes, it doesn't necessarily make the most sense.

I probably should have just bought someone's old SCCA IT prepped first gen for a couple grand and been done with it

I like competition vehicles and wanted to put one together that wasn't some raunchy "jdm tite drift missile", and reading the exploits of Fritz et al. having fun with their cars on road courses is something that I find much more appealing than going through the trouble of putting together a really nice car and then hard parking it at a show. I enjoy seeing these cars developed to a high level.

If it is any consolation, The vehicle will look completely stock from the outside, sans the current FEED hood and wheels when I am done with it (think Peter Farrell's IMSA third gens). Mazda got it right the first time with respect to the series 6 design.

Aarkaah

iTrader: (5)

@SETaylor ,

There’s a lot of good advice above from very experienced forum members. The more you customize a car beyond what is common knowledge the less valuable it becomes. At some point, a car with unique custom harnesses becomes a nightmare to maintain and consequently a deterrent to prospective buyers further down the road.

if you goal is to track an FD, clean this one up, sell it and go by a single turbo, ported, high mileage car you can beat on. Your funds will go a lot further imho.

Anyway bud, at the end of the day it is your car but just don’t want to see this thing on jacks again…. 😂

Just my .02 cents man. Send it already! 😂

SETaylor

iTrader: (4)

Sell me your blue car for $10k since the PO made his own front harness and relocated the fusebox
wrt wiring, the PDM and CANBUS integration is about as simple as it gets. All you do is run wires to everything that needs power and also run two wires to each CAN device on the network. If someone can't figure that out, they probably shouldn't be anywhere near one of these things.

I calculated the difference between selling all my stuff and purchasing a "built car" (one with a built engine), and the savings were negligible. Not after crazy power, a "small" single conversion is more than sufficient for my purposes. I would still need safety equipment and trying to re-engineer the factory wiring to get it to do what I want isn't necessarily the best use of my time or effort.

If I own this thing long enough, It too will be a "high mileage" single conversion. The end result is the same. If you can find me a roller with "good" paint, and no sunroof (due to having to spend money due to head clearance issues w/ helmet) for under $16k regardless of mileage, I am all ears

Aarkaah

iTrader: (5)

Yeah rollers that cheap don’t happen anymore. 😂

Well wishing you the best on this epic voyage! I think you may be over-simplifying things a bit. But hey, I never took any wiring or harness courses. Holler if you need anything. 👍

EREBUS

So awesome to see people like Aarkaah inspiring others and being open in assisting those who want to learn and get involved.
Thank you for helping grow the rotary community.

This build will be great!

Aarkaah

iTrader: (5)

To be honest, this infectious pay-it-forward attitude was learned from @amp. I would have never had the courage to wrench on these cars without his willingness to help and sound advice.

Standard fee for any amount of help? Lunch or a six pack. (Used to be a beer but inflation is rampant in these parts… lol)

Anyway, we digress…

SETaylor

iTrader: (4)

Hi folks, figured I'd share this since it directly pertains to what I'm doing.
I created a spreadsheet with PDM functions. channel assignment, information on current draws, wire sizing, and connector information so I can later create a full blown schematic with info on pinouts, connector locations, and other info. With this being the first harness of this nature that I am attempting to build, I have found in my (extremely limited) experience that taking the time to plan every single thing makes everything much easier when it comes time to assemble everything and later diagnose if need be.

https://docs.google.com/spreadsheets...it?usp=sharing

If you see anything that looks out of place or not advisable, please do let me know.

Pete_89T2

iTrader: (4)

Nice work on the spreadsheet! For the unknown inrush currents, you can use a hall effect current sensor/meter and do a test to characterize each of them once you've got everything wired up. Some years ago, I was having a rash of dead alternator issues on my FC. This was after I switched to an aftermarket ECU, E-fan, IGN-1A coils, fuel system mods, etc., so I decided to characterize all my current draws at steady state & inrush conditions. Purchased a simple Hall effect current sensor & digital amp meter rig from Amazon for about $20. The one I got measures currents up to 150A, with a resolution of roughly +/- 0.5A, so good enough for my purposes. Stick the current sensor ring over the alternator's B+ output wire to measure current draw, run the car & switch loads on/off in a planned sequence to determine each load at steady state and get an estimate of inrush as the load just switches on.