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Discussion Starter · #1 ·
I first bought this car back in 2005 with nothing more than a 57 trim CT26 and muffler shop exhaust so you can figure there's be a lot of changes since then. I am already going to bore the 5 or so people that read this so I'll skip a lot for the sake of brevity.

The short summary of the starting point of this thread:

I originally built this motor back in 2009 with off the shelf Wiseco 9:1 compression pistons, Eagle rods, the requisite ARP head studs and MHG, and ARP main studs. Engine management was initially a MAFT Pro before switching over to the AEM V2 PnP once Driftmotion made it available for the 7M. Head started out pretty heavily built with 2mm OS Supertech valves, Supertech dual valve springs, and some pretty extensive porting and combustion chamber porting. This head was unfortunately stolen by a well-regarded shop that has since closed and will remain un-named. I eventually built a head with mild port work, reshaped combustion chambers, 1.5mm OS Ferrea valves, and GSC beehive springs. Cams are Toda 272s that I acquired from Sixpack who knows how long ago at this point.

Intake manifold was an FFIM made by Seth of Sleeper Designs from before he started Sleeper Designs, and the turbo manifold was also made by Seth but around the timeframe he was starting the Sleeper Designs business. Ignition coils were 2JZ VVTi coils, injectors were old school RC 1000cc, and turbo is a Garrett GTX4088r. All of this brought me to 630hp & 447lb/ft on 91 octane pump. Boost pressure was set at 18psi but would creep horribly so ignition timing was very conservative over about 5700 rpm.

I daily drove this about a year before taking it to SIV 2015, where my single disk clutch finally gave up on the dyno. Having been through no less than 3 R154s, 2 of which were built, I decided to pursue a transmission swap to something more sturdy, which was quite timely as Supra Store was launching their CD009 adapter plate. While intended for JZs the adapter used an R154 bellhousing, which meant that I could make it work on a 7M with some creativity. So I got in on the initial preorder and ultimately made it work. Short story: ton of work. But now I can buy a brand new transmission that has shown to hold 1k WHP easily for less than the cost of an R154 rebuild, if you can even find the parts needed for an R154 rebuild. Clutch was put together by Clutchmasters and was the FX850 twin with an internal slave. To push the extra fluid needed by the internal slave cylinder I made an adapter to fit a Wilwood 3/4" master cylinder.

Stuffed in. If anyone tries to say it fits with some mild hammering they would be wrong.

I used a potato to take this size comparison of the R154 (top) and CD009 (the other one)

Back to the dyno for some tweaks and the car made less power and roughly the same torque. Turned out the in-tank Walbro 255 fuel pump I had feeding the external Bosch 044 (the fuel system was setup just prior to Walbro launching the 450) died and the 044 had to somehow pull fuel through a dead pump. After finding out why fuel pressure couldn't keep up I was rather impressed that it made 584hp & 434lb/ft at 18psi. Still being conservative with the ignition timing up high, largely due to the boost creep and sometimes crappy fuel at our high elevation. In tank pump was replaced with a Walbro 450 and the old school loud Bosch 044s removed.

The CD009 was typically paired with a 3.69 rear end and this led to some pretty crappy ratios with the original MK3 3.73. Rather than take the easy option of sourcing a 3.58 I did it the hard way and adapted the MKIV small diff/ GS diff to the MK3 subframe. If my decision to stay with the 7M all this time wasn't indication enough that I have a habit of making bad decisions then this should be enough. The differential in the car now is a 3.26 out of an LS430. I originally did the setup with a TT Auto diff but elected to put that in my MKIV instead. You can kinda sorta tell that I heavily re-enforced the subframe at the same time. Once everything was done the subframe was powder coated gloss black so it can forever look dirty.

The differential looks crooked in the subframe but it checks out perfectly level and straight. This annoys me to no end.....

The end result is it's a little sluggish around town but manageable. This is offset by the fact that I can get 26mpg cruising at 90+mph on the highway. Wreckless would have a better idea of how fast we were cruising back from SIV; I was watching for other things

Early 2019 I decided to change some things to better suit my liking and get the AEM setup for flex fuel finally. Changes were mostly minor but included updating the fuel setup to a Walbro 450 high pressure in-tank pump, 1ZZ ignition coils in full sequential, ID 1050X injectors in full sequential, a homebuilt intercooler using a 3" Garrett core, custom axles to replace the MKIV short side axles that I had been using (if you look closely at the right side axle in the rear subframe pic above you can see where I was using an old axle to build a template for the new axles,) and redesigned wastegate routing to stop the boost creep.


Wastegate redesign:

The change in piping to the wastegate resulted in better boost control with a single 44mm gate than with dual 44mm gates. If you're even remotely familiar with physics, like high school level physics, you'll know that a gas in motion doesn't like to change directions so that 160°ish turn to the wastegate was far less than sub-optimal. Even though it only pulls exhaust gas from cylinders 5 and 6 it manages the turbo speed far better than 2 wastegates pulling from 4 cylinders at less than optimal angles.


The end tanks were built with some 8mm Japanese sourced 6061 plate (They were originally shipping materials for some multi-million dollar piece of semiconductor manufacturing equipment) and mounts were made that allowed the use of the OEM under cover. It's a tight fit but it fits. Garrett rates the core at a peak efficiency of 950hp.

With everything back together I fired it up and drove it around the neighborhood a bit to get the fuel dialed in for cruising with the new injectors and generally check everything before dynoing. Pretty much everything checked out good except for the oil pressure sensor tied into the ECU, which didn't want to read consistently up to the point that it didn't read and killed the car. I had a good pressure gauge in the dash so I figured I could bypass this for the dyno, and did just that. And so it was off to the dyno.

I'd like to take a brief moment to point out that this is a Nissan/Infinity specialist shop, and in this picture you have two Supras and a Honda motor on the engine stand behind the red MKIV. It's unrelated to anything, just a slightly ironic point.

The result of the dyno is what ultimately brought me to the current, and hopefully last build (I have 2 other Supras in need of builds and a Ducati that needs some love)

That, is the oil filter. A billet, non-bypass filter from Canton Racing to be specific. Note the lone button head fastener on the cap, and the gap between the cap and housing. You can almost make out the sealing o-ring on the cap too. You’ll notice the lack of other bolt heads on the cap and the threads showing between the cap and the housing. Putting all this together will likely lead you to the conclusion that the oil filter popped the cap and dumped all oil pressure pretty much instantaneously. If so, you’d be correct.

Best guess is it blew right at the run up to a full power pull, but I'll never really know since I wasn't running the pressure sensor for the ECU. Back on the subject of the button head: they’re really not good for high strength applications but I needed the clearance on that one corner and I figured the other 3 original bolts provided with the filter were sufficient to keep the filter together. Ironically those 3 are the ones that totally failed. The final damage:

Number 6 and 5 spun fully and put the pistons into the valves and cylinder head. You can faintly see the impression in the cylinder head left by #6 below. Numbers on valves unrelated.

The main bearings barely made it out better by not spinning, but still managed to wear pretty significantly. Crank journals were pretty bad, and anyone familiar with machine shops will see what the big problem here is:

Those 3 orange dots indicate that the journals were turned 3 times, putting this crank at the end of its usable life. With no quick fix available here it was evident that it was time for a new motor. Pretty amazing what $3 worth of hardware can do isn’t it? I bought a full set of ARP bolts for the filter housing before I even finished the motor tear down, so we won’t be repeating that one again.


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Discussion Starter · #2 ·
While I had a usable 89+ reinforced block on hand I did not have a fully counterbalanced crank, so the search began and as it became evident that finding one in good condition was going to be difficult I decided to do the only logical thing there was: build version eleventy-thousand. Or: current build. With a clear picture of the desired end and possible final, state I started the process with the body work.

It’s a 32 year old car (build date of 7/89) with original paint outside of the bumpers and side skirts, so it’s showing its age and now is as good a time to refresh it as any. The factory paint is 043 white, just a plain old boring white, and I’ve always wanted to change that over to diamond white pearl. After a bunch of back and forth I settled on going with super white instead, which worked out great as I ended up acquiring a white pearl mica from Wreckless not long after getting paint on the car. While two pearl white cars isn’t necessarily a bad thing I still don’t really want two cars of the same color.

Engine bay was stripped down mostly bare and unused holes filled in. The plastic nuts for the fender liners were replaced with welded nuts. If I were to do this again I would just weld in acorn nuts for a slightly cleaner look.


And painted

This was painted in the middle of January, hence the propane heater in the back. Had to run it for an hour or two to get the garage warm enough to maintain a temp high enough to spray and cure since running the heater after spraying would be turning the garage into a bomb essentially.

Some minor eggshell along the back seam but otherwise the paint went on smoothly.

One key area to point out is the seam along the firewall under the clutch master cylinder and brake booster.

Pretty much impossible to see but it’s a common spot for rust to form from brake fluid leaking from the clutch MC. Pretty easy to not think about but if it goes for too long you end up with something like this in the driver side floorboard:

That channel is the frame rail and not something you want to rust out. I thought I was proactive with stopping the rust from this years ago but never took the time to pull up the floor board insulation, so this stayed hidden.

Stripped the rust off, treated it, welded it back together, and coated it with an internal frame rail coating from Eastwood. Pretty neat stuff that makes it easy to get into confined areas like this. I tried to get pictures of this but getting pictures of the inside of a black frame rail proved to be difficult and my little inspection camera just wasn't up to the task, so you'll have to use your imagination and picture a pretty gloss black interior of a frame rail.

Moving on to the body I stripped it of pretty much everything but the windshield and hatch glass, windshield because I am stubbornly clinging to the OEM glass since it is no longer available and the hatch glass because it has a bad habit of breaking when you try to remove it. Don't ask me about removing it later on to swap to my daily 87....

Outside of the usual dents in the fenders from leaning over them to get to the engine bay there was some minor hail damage on the roof and rear quarters under the quarter windows. This was easily fixed with a couple coats of filler primer.

The larger dents, like the ones in the fender from some careless maneuvering of metallic objects and the dent/crease in the rear driver side quarter required a little bet of encouragement from a hammer and dolly before getting the primer. After some hammer massage:

You might also note the filled in mount hole for the 3 piece spoiler. I don't use it anymore so those holes were filled with some sheet metal cut to shape and TIG welded in.

The Bomex replica rear add-ons were always a little bit off. I can't take full credit for this as I bought the rear bumper with them already attached and "molded in", but they weren't smooth or even from side to side. Fortunately white hides a lot of sins in pictures so I don't really have anything to show this, but it was there.

The top of the add-on just hanging out on top of the bumper

All those different colors should give an idea of the wavy-ness of the add-on.

After a bunch of sanding and what I consider to be a lot of filler (most body shops would consider the amount of filler a good start), smoothness. Only took me 2 weeks to get these where I wanted them…


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Discussion Starter · #3 ·
The Bomex side skirts (again, replicas) fit just about as well as the OG Bomex sides, which is to say not well. I had played around with the fitment on these for several years and finally settled in on liking them better when mounted in reverse of what Bomex intended. Ironically they fit reversed just as well as they fit normally, which isn't great.

The fender end never lined up with the fender

The lip that was intended to serve as a mount to the top of the rocker was never in a position to serve as a mount, and just kinda arbitrarily stopped short. Parts were too thick and hit the bottom of the door as it closed, and parts were at such a steep angle that it would rub on the rocker, distorting the side of the skirt. Needless to say, the gap along the bottom of the door was horribly inconsistent.

Started out by cutting the front of the skirt and stretching it out to line up with the fender

Fiberglassed in

The top lip was cut off and the top sanded level, which ended up removing a significant amount of fiberglass and unfortunately these are made out of chopped mat, so not very strong. Fortunately I have a bunch of 9oz heavy weight weaved fiberglass and used that layup some reinforcement on top.

Roughed it up and laid on the filler

Couple more coats of filler followed by lots of sanding gets me a nice gap along the bottom of the door.

Don't currently have any pictures of the insides of the skirts but they were reinforced and smoothed to leave a good mounting surface on the rocker panel, as well as a smooth surface to mount to the bottom of the car body. The front skirt mount was made to work with the fender liner and the rear was made to work with the lower trim panel that sits below the trim piece behind the door.

The other side was repeated this way and I am pretty sure it took me a month and a half to finish these.

Continuing the trend with the front bumper cover, the grille was cut out to make room for the Shine Auto Project S2 replica air guide. I ended up sanding the flange areas around the edge of the guide down to sit semi-flush with the bumper cover, then drilled the bolt holes for the bumper cover mounts under the bumper. Once I had everything lined up where I wanted it I glued it in with structural panel bonding adhesive, which is kinda like JBWeld on some pretty serious steroids. Basically the stuff that OEMs use to bond composite panels together when bolts/screws/rivets are not possible.

With that semi done I moved on to the OG Bomex front lip, which fit like everything else has to this point.

Could have sworn I took pictures of just how far forwards this thing stuck out in the center but I can't find them, so you can figure it was pretty far out there based on how far out the sides were.

After a bunch of cutting and grinding I got it finessed to the point that it lined up completely across the bottom of the bumper cover, and aligned with the sides of the bumper cover. I can't find the pics of the sides or after fiberglassing it but I stopped here, so I'll add those in later on when I get back around to finishing the lip.

I'll note that that fit is with only 2 bolts on each small side piece holding the entire thing up.

Stopped here to get the car sprayed with the final coat of epoxy sealer before paint.

With the final sealer coat on and everything looking good for paint, it was time to take it all back apart again to spray.

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Discussion Starter · #4 ·
I don't have a lot of space in the garage so the whole body was sprayed and after that cured I painted the fenders, roof, doors, mirrors, hatch, rear rocker/mudflap cover thingies and headlight covers.

Unfortunately it was entirely too cold when I painted the body so the clear didn't really lay out smooth. The bigger problem was a big gust of wind that blew my fans and filters over, sending a bunch of sand and other debris all over the fresh clear coat. There wasn't enough clear left by the time I got done sanding the crap out so it was going to need a redo. I got an inflatable paint booth later on and resprayed the car but the pics above are prior to the respray.

If gnats ever go extinct I have some genetic material preserved in some clear coat that we can use to ensure they stay extinct.

Underside of the hatch, so not really a big deal, but still...

Put the doors and hatch back on to see how it all looked and decide if I wanted to cut and buff it

Both awesome and depressing to see at the same time as I knew I had to go back and redo the body, but everything else came out alright.

Fresh off the disappointment of knowing I had to redo the body I moved on to some detail work of the door mechanicals. This is the sort of thing that always draws my attention and even though it's never seen once the car is together I know it's there, so it has to get done.

The door latch and associated arms as removed:

The guts

Stripped the assemblies down as far as possible without grinding rivets and thoroughly cleaned it all up. Parts that could be re-plated got a fresh zinc-nickel plate and everything else got coated with some fancy paint that uses actual stainless steel in the pigment to prevent corrosion. Moving parts got a coating of moly dry lube before getting fresh grease. Nuts, bolts, and screws were replaced with stainless hardware.

Window regulators received a similar treatment but the plating was in excellent shape so it was really just a clean up and re-grease/dry lube with stainless hardware replacement.

Doors partially assembled

If you've ever fully disassembled a mirror you probably know that the plastic is hard and brittle, and the tapping screws like to make things worse. My mirrors were no different and a few of the screw holes were either stripped or broken. JB Weld to the rescue here. Built up the broken plastic studs, re-drilled the holes, and heli-coiled them to use machine screws. All stainless of course. Metal brackets all got a coat of suspension epoxy from VHT. It's not the greatest stuff but it covers eventually....

Exterior door handles don't really have much to do to them but there is one rather important thing: the rubber stops.

Not having these ultimately leads to cracking the door handle body from the latch slamming down on the cast handle body, and these seem to be missing more often than not. It was a while ago that I bought these but the were still available from Toyota for less than $1 each.


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Discussion Starter · #5 ·
Headlight buckets were up next. Started by grinding off the rivet that holds the hinge bearings in and pulling the fiberglass bucket separate of the mount bracket. I skipped photographing most of this because the buckets were shedding fiberglass and making life unpleasant, but once everything was disassembled it was cleaned up and painted. The mounting bracket got VHT suspension epoxy spray paint, which was a mistake that I had to go back and fix later, and the fiberglass buckets got a full can and a half of the black VHT suspension paint. This was done out of a great dislike to getting fiberglass fibers embedded in my hands and arms and a growing distaste for VHT suspension paint. Looks good though.

The hinge rivets got replaced with a bolt and a sleeve so the entire assembly is now serviceable, which really isn't necessary outside of me needing to go back and strip off the white paint to redo. The screw holes in the buckets got heli-coiled to take machine screws just like the mirrors.

The headlight motors were pulled apart, cleaned up, and re-greased. The body was painted titanium blue, I don't know why, or even how I ended up with titanium blue because it matches absolutely nothing else on the car, but I kinda liked it so there it is. I may go back and respray it silver or black some day. The mounting bracket for the connector was getting re-plated so it's missing in the pic

While the door hinges were done at a much later date than all of this (i.e. closer to me posting this than closer to when I did all the stuff I am posting now) I figured it fits in here.

The MK3 has some long, heavy doors so we've probably all seen or dealt with sagging doors at some point. Rather than play the game of gamble $200 on a pair of driver side door hinges and hope they sag less I decided to venture off into the land of simple creativity.

Started by grinding the head off the hinge pin rivet, pressing it out, and removing the bearings.

The OEM bearings measured out to 8mm ID, 10mm OD, with a 1mm thick flange.

Wanting to make it a bit sturdier than OEM I sourced out a couple different size bearings. All were 8mm ID but the OD and flange thickness varied. One set was 11mm OD and a 1.5mm thick flange, this set I would use on the driver side door as I don't have a good spare set of these. The other set was 12mm OD with a 2mm thick flange and was used in the passenger side hinges since I have a couple spare sets of these. The ones pictured here are the passenger side. The hinge pin was replaced with a socket shoulder bolt, 8mm diameter 55mm long shoulder. The shear strength on these stainless ones was around 45k psi, which far exceeds that of the bronze bushings so I didn't see the need for a higher grade shoulder bolt.

Both sets of bearings required removing material to fit the larger dimensions, with the passenger side obviously requiring more removal. Only time will tell if too much material was removed, which is why I chose to use the larger bearings on the side that I had spares for. In the process I found that, based on wear patterns, the hinges weren't totally parallel to the bearing flange, which resulted in the bearing wearing faster in that area. This may have been caused by that spot being at a point where the door was open and subject to it's highest load or the hinge itself not being truly square from the factory. I can't tell for certain but I'd bet it had to do with the weight of the door in that particular location of travel.

After rebuilding all 4 and painting. Top row is the driver side and you can sort of make out the difference in bearing flange thickness.

Still avoiding the need to respray the body I decided to move on to rebuilding a steering rack. While the original rack for the car was still good I wanted to get rid of the PPS as it was no longer functional with the work I'd done to the car and I wanted the slightly quicker ratio found on the earlier MK3s. I sourced a rack from an 87 turbo, probably one of Wreckless' cars that I had torn apart, and stripped it down.

All of the internal PTFE seal rings and shaft seals were replaced and some light scuffing on one end of the shaft was lightly polished out. The adjuster set screws and lock nuts were nickel plated.

After assembly it got painted with the unknow reason titanium blue along with black. Made new hard lines with 1/4" stainless tube and new fittings, along with the brass flares that press into the rack for the fittings to seal on. New Superpro bushing and OEM boots were also put on.

Steering shaft got some attention too

Still moving on with assembly stuff even though I still needed to respray the body I got started on the brake lines. Car had ABS but with the 6 speed swap I no longer had a rear speed sensor that would provide the correct signal for the ABS ECU to do its thing, so out the ABS system came. Given my appreciation of stainless steel it was only natural to make these out of stainless tube and stainless tube nuts. Got the clutch hardline redone at the same time.

If you're wondering why I didn't do this before painting, I am too.

Through the judicious use of painters tape and microfiber towels I managed to get this all done without scratching the paint. You can also note that the titanium blue paint made an appearance on the wiper motor body too.

The grommets for the brake lines into the wheel wells is missing in the pics because at the time I was unable to source new ones. Fortunately I was able to source some directly from Japan, using the part number below.

Somewhere around this point I decided I should probably paint the side skirts and rear bumper cover, so I did that.

The clear did not lay out very smooth here so I'll have to sand it and buff it, but sometime recently my two new puppies decided to play under the rear bumper and leave a few deep gouges in the side of the bumper that I'll have to fix at some point.

The steel bumper supports, or crash beams if you prefer, were sand blasted and painted with a chassis enamel from Eastwood. Once this stuff cures it's pretty hard and durable and appears to be a decent substitute to powder coating. The shop that did my large item powder coating closed so I had to find some sort of alternative.


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Discussion Starter · #6 ·
To continue with the theme of doing things in the improper order, I moved on to another small thing that's almost always bothered me: the spare tire well.

I relocated the battery to the spare tire well (the rectangular outline) when I went FFIM to make room for intercooler piping and that area back there just isn't very well laid out for that sort of thing. So that whole panel came out. Battery and surge tank in approximate desired locations.

Then started with a big sheet of galvanized 18ga steel, even though I specified and paid for bare steel, and got an access hole cut for the fuel pump hanger. I elected not to worry about the fuel level sender as I've never had the need to access that with the tank installed.

Then battery and surge tank cutouts, followed with bead rolling to add some rigidity.

Once the panel was welded in place I made the battery box and surge tank supports with stainless steel angle, because that's what I had.

Top 2 fittings are the feed from the fuel tank and the return line to the tank. The lower 2 are the fuel pump out to the filter on the right, which may or may not be done with stainless hardline.

Filter outlet to the fuel rail and the fitting on the surge tank is the return line from the fuel rail. With this setup the lines can be disconnected from the surge tank, fittings capped, and whole assembly removed through the top without dropping the tank. While I don't plan on having to service fuel pumps that often it'll be nice to know I don't have to worry about dropping the tank to get it done, and the filter is right there too.

With that done, all seams got seam sealer and the underside, topside of the panel, along with the interior of the car, was sprayed with an epoxy sealer. Then covered with Eastwoods sound deadening mat because it seems to work just as good as the Dynamat at a much lower cost, and the aluminum backing seems to be thicker on the Eastwood stuff.

Really glossy and good looking for just a sealer

Following that, the interior of the battery box was lined with EPDM rubber. The interior of the car was covered with a fire resistant padding insulation, 1/2" under the carpeted areas and rear seat and 1/4" in the hatch area, including the underside of the rear cover. While I don't have any good pictures of it, the wood cover was worked over almost completely. The braces on the underside were moved to accommodate the new layout underneath it and extra mounts were added to compensate for the loss of a fairly significant amount of support added by the spare tire. The wood was sanded smooth and resealed on both sides prior to adding the insulation padding to the underside.

I made some cover plates for the access holes, but ended up just using a laser cut round plate for the fuel pump hangar because the not-round round cover bothered me.

To get proper clearance for the surge tank bulkhead connector I had to elevate the cover a bit. Not wanting to mess up the insulation and paint I used some 1" aluminum channel to build a standoff. Seams were seam sealed and gaskets will be cut for both access covers to keep things under the car from seeping into the car. Fuel vapor in cabin is no bueno. The battery box is sealed to the cabin with the EPDM rubber lining and the box lid from a Taylor battery box. I used an AN fuel cell bulkhead fitting to vent the battery box to the bumper area behind the fuel tank.

Super long screw is because I didn't have enough of the right size countersunk screws in the right length, so that was a temporary fix until I got more of the correct length screws.


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Discussion Starter · #7 ·
Around this point is when I decided to respray the body. I was pretty grumpy about having to do it still so there's no pictures but the paint came out fairly well, my only complaint with this redo would be that the extra work wound up leaving the rear quarter wheel well lips not very well defined. So instead of a crisp edge transitioning to the quarter panel it's just kind of rounded and smooth. It doesn't really look bad and in the eye-searing super white you can't really see it unless it's dark out so I haven't decided if it's worth fixing or not.

Given that I had been doing something paint and body work related for roughly the last year and a half or so, to include full resprays of a couple other non-Supra cars, I was pretty burnt out on it, so it was on to something that everyone else seems to hate but I actually enjoy: wiring.

This car's been through a lot since I acquired it and even more before I acquired it, so the wiring has been a bit of a mess the entire time. There was an aftermarket alarm installed by the previous owner and it wasn't installed in the best of manners, resulting in issues with the factor theft deterrent system. I "fixed" this with some band-aid work but there was still T-taps in wires, random wires routed to who knows where, etc. Then to top it off there was wiring from aftermarket gauges, both previous owner and mine, that had been routed along various harnesses and tapped into power in various places. And if all that doesn't sound bad enough I went through 2 different piggy-back ECU setups that resulted in some interesting wiring work under the dash......

There's also the main body wiring, but this post is already getting to be wordy, so I'll just say that was a mess too. Given all of this I did the only thing that would make a proper wiring job, and that was to remove all wiring from the car and go through every single wire. A lot of the harness was stripped of non-functional systems, some stuff was simplified, some re-routed, some rebuilt, and some completely new. 95% of the wiring I replaced was replaced with M22759/32 Tefzel wire, 4% was TXL wire, and I repurposed roughly 1% of the OEM wiring when I couldn't get what I wanted in Tefzel. Numbers are approximate

This really terrible picture from 2015 should give you a decent idea of what I was starting with.

I must have been practicing for taking pictures of bigfoot or ufos...

Starting up front, the dash was removed and everything else behind it.

Just look at that disaster of an OEM harness. And the 2 strange looking yellow and red caps. Those aren't stock and they're new. Those caps are covering MIL-26482 bulkhead connector for the engine wiring harness. The main harness (yellow cap) is in the original speedo cable hole, not used for that anymore as I've gone to an electric speedo, and the smaller secondary connector is in a newly made hole just down and left on the fire wall.

This combo will cover pretty much everything I need on the engine harness with space left over in case I decide to go to a DBW throttle body setup.

With those in I started on the main body harness that runs behind the dash. ABS, TEMS, automatic climate control, PPS, cruise control, and factory radio components were removed. The main fuse and relay blocks on the driver side were reorganized to minimize the need for adding additional circuits to an additional fuse block elsewhere, and to move some of the fuses originally in the engine bay fuse block to the cabin fuse block. The junction connectors were gone through and reduced to smaller connector housings when the number of circuits was reduced, and wiring added for new systems.

That little pile in front of the rear wheel is about 2/3 of what was removed from the body and dash harnesses. The ignition switch wiring was redone to simplify the routing and shorten the wires for the starter solenoid and switched ignition power to the motor. Wiring for all of the engine management stuff was added in and routed to the proper junction plug based on where it's going.

Wrapped up and back in. Harness wrap is TechFlex F6 and the zip ties were ultimately replaced with self fusing silicone tape.

The body harness to the rear was almost completely remade and minimized as much as possible to help fit the monster 2/0 battery cable all the way to the rear. The tail light wiring was replaced with all new Tefzel wire and the light failure sensor was eliminated. Instead of running all the way to the back along the driver side sill these pass over in the harness that goes over the tunnel before going to the hatch. The only real reason for the change in routing was to give the battery cable enough room to mount tight enough to the body to get the interior panels to fit properly. Previously there was a decent sized gap between the panel next to the back seat and the carpet and you could see the harness through there. The flimsy black oxide clamps that hold the plastic harness channel to the car body also got replaced by some sturdy aluminum strap. I shaped the tops of these to hook into the green plastic strip along the edge of the carpet to help hold it in place in lieu of the usually broken mounting tabs that clip into the rocker.

The coil of black and blue wires coming down the back side of the strut tower is the new speaker wiring for the front speakers. RCA cables were later run separate of the harness since they're super bulky and difficult to route smoothly.

The wiring for the O2 sensor also runs part-way through this side harness before branching out right where the original power seat wiring once was to another MIL bulkhead connector on the tunnel. The reverse light switch wiring is also in this harness.

The little fuse block you see off to the side in the hatch is the PDM for the fuel pumps. Each pump has it's own fused power feed and relay, and each relay has an individual trigger wire going to the ECU. It's a little on the big side but there's room to expand to 4 pumps total ( 1 in-tank, 3 surge tank) if needed. The 3 pump power wires run out through the stock grommet used for feeding wire to the fuel tank, along with the wires for the fuel sender and rear wheel speed sensor.

The main battery cable runs through the front firewall into the fender well through a hefty bulkhead connector rated for 600 amps

All the way to the hatch where it connects to the main PDM block.

The switch can be manually used to disconnect the battery from everything or there is an option to wire in an external switch that will disconnect or connect the battery. As of now I am only using the physical disconnect. Large orange wire is the power wire to the front that connects to the alternator and provides power to everything but the stereo amplifier and fuel pump, which are the other outputs on the block. Each output is individually fused.

Power cable gets into the battery box through a sealed grommet and the ground attaches to the chassis in the box on part of the stainless angle that the box is made of.

The ground is attached via a stud that passes through the box to the underside of the car so I can add a large ground cable to the front if the need arises. I've run the relocated battery without one going up front for close to 10 years without any issues so I don't see doing it, but I'd rather have the easy option of doing it already in place just in case.

Back up front on the other side of the firewall there's this goofy jumper thing

This transfers the power from the main battery cable to pretty much everything. The main power wire to the fuse block in the driver side kick panel connects to one of these bolts and the power wire that feeds the fuse blocks in the engine bay tap into the other.

The fuse block on the firewall has the AM1, AM2, and RTR fuses. The small PDM is the headlight relay and fuses, and the hazard/horn fuse.

And because I don't like electrical fires (fires in general really) a redundant fuse on the main power line. The other side of this block attaches to the alternator and starter. It's home made with a 1/4"x 1/2" solid copper bar and solid copper studs mounted to a solid PTFE block with a channel milled into it to sink the copper bar into it. I'll end up either nickel or tin plating this eventually.


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Discussion Starter · #8 ·
Then I moved back to the dash and ECU wiring.

The ECU wiring was rather easy as I'd mapped it all out before hand, so all I needed to do was crimp the contacts to the appropriate wire, stuff it in the correct location on the receptacle, and cut it to the approximate length needed. The 3 wires that break out in the middle of the picture are the switched ignition power for the injectors and coils (red wires) and starter solenoid (blue). This entire harness is completely new Tefzel.

Since this isn't a race car and I intend to have a fully functional HVAC system, including A/C, the harness needed to clear the main HVAC assembly that sits right in front of this, so a 90° boot on the large harness was used to get the bundle going the right way.

With the HVAC assembly in everything just clears enough to not interfere with anything.

When looking at those pictures that lone phillips head screw annoyed me, so the next time I had the assembly out every screw was removed and the holes heli-coiled to accept a regular stainless allen head screw. Cause I'm OCD like that.

The harness ends up routing over the HVAC assembly and over to the ECU location just above the glovebox. After I have the ECU in and the harness fully terminated I'll go back to this area and mount the harness to the HVAC box to keep it from rattling around and making noise, even though the harness wrap is supposed to stop that.

The dash wiring is another harness that ended up largely gutted, mostly due to all of my gauges being aftermarket and the stereo only needing basic connections like power and ground. Previously there was wiring strung all over the place and there were random junction connectors to fit the extra wiring for all of the added stuff over time. I managed to get all of that knocked down to this one junction here and one that comes out the lower side of the dash that plugs into the main fuse/relay block. The gauge power and ground was tapped into the factory pins in the junction blocks hidden off to the left side of the pic. Gauge lighting was pulled from the illumination power prior to the dimmer switch as the gauges use their own dimmer that gives a wider range than the stock one does. The OEM dimmer was left connected for essentially just the climate control lighting, and accessory port lighting.

The smaller white connector off to the bottom of the above pic is the wiring for the pillar gauges. All of the connections for these gauges minus the thermocouple wiring for the EGT gauge run through these.

Since the cruise control was removed long ago I decided to try and make the stock cruise buttons on the steering wheel work for turning the stereo on and adjusting volume. It's a universal steering wheel controller that can be programmed to work with a wide range of signals so the cruise buttons varied resistance setup should be usable for this. Like everything else, the wiring for this was routed through the harness to appear like it was there from the beginning.

At this point the dash wiring was as done as it needed to be given that the gauge cluster wiring could be finished with the dash in.

The uncovered bundle is the unfinished cluster wiring. Even with that unfinished it's still far more organized than previously.

If you've ever had a dash out you've seen the ugly rusted dash cross brace. You can imagine from everything so far that I am not a fan of that, so the rust was stripped off and everything painted, leaving just enough bare spots for the grounds to work.

All of the screw holes on the dash were also heli-coiled for the usual stainless allen head screws.

With interior wiring about as done as it could be at this point I went on to the front body harness. Not much of the OEM harness is here outside of a couple headlight motor wires that were unavailable in the colors that I wanted in Tefzel, so the original was used. Wiring was added for a PWM signal and switched ignition power to a Mercedes PWM fan controller that's supposedly good for around 60 amps constant. Unlike pretty much all of the aftermarket PWM fan controllers this one can be fully controlled by the ECU to activate and ramp up speed at any curve I desire, and can also be shut off at speed so as not to hinder airflow. Minus the PWM control I had my previous fans controlled this way and it made for much more efficient cooling on the highway. The controller also has a built in soft start feature to essentially eliminate any current spike on fan startup.

I had previously removed the factory horn wiring so I figured now was the time to add it back in. Also added in was a speed signal wire for the MR-S electric power steering pump tucked away in the fender (I'll cover this later). The main power wiring hasn't been added yet but none of that will go into the cabin, so it's not involved in this harness.

The incandescent headlights were removed in favor of Trucklite LEDs that have a combined max current draw of 6 amps, so the factory wiring was removed and replaced from headlights to switch with 18ga Tefzel. I could have technically gone with smaller but I like 18ga.

Headlight motors got new wiring, save for the 2 previously mentioned OEM wires, so the harness bundle was fairly small at this point. Small enough that I could route it behind the headlight bucket brackets and under the top radiator support, neatly and safely out of the way of everything.

The 2 wires heading off to the engine bay are the AIT sensor wires. Given that this sensor is closer to this harness than it is the TPS on the engine harness I decided it was better to move it here rather than run it through the engine harness. Also saved me another pin on the bulkhead receptacles and made it so I could pull the motor without having to disconnect the AIT sensor. This means every single connector on the engine harness save for the starter solenoid can stay connected while the motor gets pulled.

The headlight motor wiring is not terminated yet as I am having some difficulty acquiring the small terminals that are used on these connectors. I have confirmed that they are in fact not only still made, but available from Yazakis North America distributor, but no one wants to order any. So those will hang loose until I manage to acquire the terminals.

Turn signal and running light wires were completely replaced along with the harness side connectors.

The temptation to replace the wiring on the sub-harness for the turn signal housing is high, but I really don't want to deal with chasing down the special terminals in the bulb sockets while still trying to get the headlight motor terminals, so they're safe. For now


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Discussion Starter · #9 ·
With most of the wiring done and the remaining wiring requiring me to finish other things before doing that wiring, I moved on to other things.

I finally put the quarter windows back in, and replaced the hatch glass that I scavenged for my 87 a while back. I really just wanted to get these things out of the way and help minimize dust and junk getting into the car.

Not much quite like hoisting a $900 window over the back of the car with a couple of suction cups...

The quarter windows got new mounting clips up top, and the hatch glass got new positioners and top trim mounting clips. I have all new trim for the hatch that will go on eventually.

With that storage space cleared up I went back up front. If you'll recall me mentioning something earlier on about regretting some "epoxy" paint this is where that comes in. It turns out that the "epoxy" paint isn't a true epoxy, which is evidenced by the fact that there was no mixing involved, and it has a pretty bad interaction with acrylic urethane when the pieces are clamped together. Like the front headlight bucket brackets that sit on top of the front radiator brace. The result is the urethane and "epoxy" bonding together and separating from either one or both of the parts. So now the "epoxy" needed to be stripped. Unfortunate as it turned out to be a rather durable paint. Even more unfortunate that I painted everything forward of the upper radiator mount with this stuff, including the lower radiator support.

It all worked out though as I needed to remove the OEM lower radiator mounts to make new ones to fit a modestly larger PWR dual pass radiator.

Some rubber isolation mounts, similar to the OEM lower mounts, fit in the holes and give the radiator the room needed to expand and contract as it heated and cooled.

Fit check on the under cover:

Clears without touching

Fills in quite nicely

And leaves me with a whopping 1/8" clearance between the front of the radiator cap and hood. I failed to account for the different location of the cap when sizing this out with PWR, so it's a bit closer to the hood than I originally intended, but it'll work.

Upper mounts will be done once I get the shroud done as they will wrap around the top of the radiator, including the shroud.

A/C has been removed for probably close to 15 years at this point so I decided that rather than chasing all the OEM stuff down I'd just start fresh. I elected to go with a smaller than OEM universal crossflow condenser from Vintage Air. With the smaller condenser it may not blow the coldest air around, but it'll still be colder than ambient air. And worst case I can always put a bigger one in.

Made some simple brackets to hold the condenser in place, off to the driver side of the opening. This'll give me room to either mount an oil cooler in the open space or just leave it empty to allow fresh air to the radiator core.

Not wanting to keep the stock location of the drier in front of the radiator I chose to move it elsewhere, ultimately settling on the inner fender on the passenger side. I didn't have the drier on hand but fortunately it turns out to be essentially the same size as a Monster can. I have plenty of those.

The A/C hard lines will eventually run up along the inner fender to the hole leading into the engine bay, next to where the ABS module usually sits. The pressure switch will likely end up somewhere over there as well.

The oil filter and thermostat were also relocated while I had the paint stripped in case I decided I needed to make some new holes, which I did.

I made some actual brackets for the filter instead of the flimsy t-bolt clamp mount, but I evidently didn't take pictures of that before removing everything for paint again. The thermostat used one existing hole and I just drilled and tapped another. Got 3 threads of engagement so it should hold just fine with the other side.

Hopefully that was all I needed to modify because from there I finished stripping the epoxy paint, rolled it outside, and primed and painted it. Again...

With everything the proper 040 Super White it was back to assembly time. Some things will be coming back off later on for various reasons, like painting the condenser brackets or other miscellaneous finishing work.

Doors went back on with stainless ARP hardware

Door stop hinge pin got replaced with a stainless shoulder bolt. Mostly because I couldn't find the new OEM pins that I bought, but the shoulder bolts fit well with all the other stainless stuff around there.

Condenser and radiator in. Condenser brackets are currently just primer and will be painted black when I have more than just those to paint so I don't mix up paint for just a couple tiny brackets.

Oil filter and thermostat in, with the top filter mount bracket visible. I still haven't remembered to take a picture of the lower bracket.

Actual A/C drier in. The 2 black fittings in the back are for the hard lines from the condenser to the drier and the suction from the evaporator back to the compressor.

The chassis grounds on the frame rails up front were tin plated before painting so there's no bare steel to worry about corroding. May be a bit excessive but there's going to be a fair bit of current grounding through here.

Looking back at the picture I probably should have polished it up a bit before plating it....

PWM fan module and PS pump back on. The lone ground wire is for the headlight motors and horn. The radiator fans and PS pump will also ultimately ground here.

Ground bolt and washers are brass because they just seemed classy, and go well with tin plating.

Fenders and bumpers back on. Driver side fender will likely not need to come off after this but the passenger side will come off to bend the A/C hard lines.


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Discussion Starter · #10 ·
With this starting to look more and more like a Supra you would think it would be logical to start doing some motor stuff, which is precisely why I am not doing some motor stuff yet.

Those of us with targa cars will all know the wobble and chassis flex that comes with the joys of having a removable roof. While I enjoy a spirited drive up/down a mountain or two I certainly don't enjoy the wobbles at speed or the disconcerting twisting under heavy cornering, so steps were made to reduce this. First was acquiring a DoLuck rear cross brace, which helped a fair bit but did leave a bit of flex and wobble still. This came in sometime around 2007.

Following that was a harness bar that crossed behind the front seats and attached to the upper seat belt mounts. With the interior trim removed it worked great, but this is not a race car and I wanted a full interior so it came out.

Then by pure chance I came into possession of a targa brace made by a member of Supramania (projectsupra IIRC) in 2008ish. This one was unique in the fact that it stayed installed in the car whether the roof was on or off, and didn't require you to carry it around and install it whenever you took the roof off. (Excuse the poor picture quality, it was 2008 and I was too poor to by a real camera)

With some minor trimming of the interior panels, no panels needed to be left off for the brace to fit.

Whether it was the targa brace or the combination of the targa brace and DoLuck brace there was absolutely no flex or wobble of any kind. It may have actually been stiffer than the stock setup with the roof on at this point. I could stick a jack under one side of the front subframe, jack the car up, and open and close the doors without any rubbing or issues. This setup has been in the car since sometime early 2008 and many roof-less miles have been enjoyed since.

If you're one of the unfortunate few non-short people that has ridden in my car you've probably hit your head on this thing at least once.

And it's heavy. While that may not seem like a problem since once it's installed it stays installed, the design of it means it can be a problem. The front of the brace was held up by the little tab that the factory bolt retainers screwed to, and was only supported by that little thing until you got some nuts on the front bolts after taking the roof off. The targa top isn't the lightest thing around and can be a challenge to get off safely with one person, and now with this brace occupying a fair amount of space it gets even harder. This resulted in leaning on the brace a time or two, ultimately tweaking the brace ever so slightly.

Here we can see the rear mounting tabs are roughly 1/8" and are all that anchors the brace to the car with the front unbolted.

While these things didn't appear to be an issue with stopping the wobbles they certainly bothered me, as these small details often do. So my dumbass decided to make a new brace, and here we are on another detour of the build.

With weight in mind I decided to go with 6061 aluminum tubing with a 1/8" wall. Front and rear mounts are also 6061.

Rear mounts were made from a solid bar of 6061 and designed to hug the rear body side targa mount and body. Fronts are basically a large, glorified 1/4" thick washer with a countersink for the mounting bolt.

The sheet metal around the front mounts was welded up to help add strength over the factory spot welds, and then the holes for the OEM mounting system were drilled and tapped to allow the front mount to be bolted to the body full time. The mounting bolt (not pictured here yet) currently just has a hole drilled through the center to allow for bolting the roof on, but will eventually be counterbored on the backside to accommodate a retaining ring to hold the bolt in place on the mount until the roof is bolted on, or nuts put on the targa bolts to prevent rattling.

Since I wanted this to hug the interior of the roof more closely, rather that just going straight across, I ran a piece of square tube from the rear driver side mount to the front passenger side mount. Bending square tubing in a consistent and clean manner is nearly impossible for us mere mortals, so I notched the tubing and bent it to shape.

Because notching the tubing takes a lot of the strength away I fit a piece of 1/8" plate to fill in the notches. This should add a bunch of strength back in over just welding the tubing back up.

The other cross brace was a little different since there was another tube in the way of running a single piece all the way across. Here a piece was cut for both sides to meet in the middle on the other cross brace. Just butt welding a couple pieces of tubing to another piece of tube doesn't seem very strong so I cut a piece of 1/4" plate to run across a notch cut in the full length tube, and down either side of the 2 piece tube roughly 6" on both sides. This was spot welded to the bottom of the tubes and the top got a full length weld.

Bottom side:

Top side is visible in a later pic.

It was about this point that I forgot that the main reason I was stopping to take pictures is because my poor air cooled TIG torch isn't rated for this kind of abuse, so I abused the torch and neglected the pictures. A few things were done without pictures, like spot welding the tubes to the rear mounts, welding in 1/4" plate braces to the front tubing going to the mounts, spot welding the tubing and braces to the front mounts, and a couple gussets were added to the larger angles on the front and rear of the brace.

You can see some of that here:

You can also see the blown out weld from someone forgetting to clean prior to welding.... Also I suck at overhead aluminum welding so this was greatly exaggerated from a normal poor weld.

But square tubing is ugly and I have my doubts as to how strong this would be, so round tubing was cut in half (length wise, which was fun) and welded on the sides of the square tube. I followed the same pattern here with the 1/8" plate being added in the notched areas prior to welding.

Going to the rear mounts I wanted to add some more braces for extra strength over just a piece of tube welded to a flat plate, so another 1/4" plate piece was cut to run up the square tube roughly 3" and out onto the flat plate welded to the rear mount. No pictures, so I guess you'll have to use your imagination for now.

With the mounts braced up I finished welding everything up and threw it on to check the fit. A little bit of shrinkage pulled the front mounts out of alignment with the body but not enough that grinding the holes out wouldn't fix.

By this point my overhead welding was as good as every other position so I was pretty happy about that, my TIG torch on the other hand started to melt the rubber coating on it and wasn't very happy...

From there I smoothed all the welds out (except for one, but we'll pretend for now that I didn't forget about it) and gave it a final test fit.

Rear mount fits without additional trimming of the interior panels and gives sufficient clearance around the targa

Unfortunately the front mounts won't clear the front trim as is so I'll have to adjust that before the upper trim panel goes back in. Clears everything on the targa just fine though.

Much closer fit to the targa than the old one


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Discussion Starter · #11 ·
Satisfied with the fit of it I decided to go with something closer to the interior color instead of wrinkle black. While I failed miserably at that I kinda like the color, so we'll see how bad it looks with everything installed. I just finished respraying the front body where the paint was stripped for welding, so that'll have to dry before I can mount everything back up.

Color is cobalt blue metallic.

Front and rear of the body were sprayed with some super white single stage since I am not sure how much of the body will be visible yet. This is what I am currently waiting for to dry.

And that brings me to current status, for the most part. I've skipped over a bunch of stuff, like stripping and re-plating suspension hardware, powder coating hubs, a collection of a bunch of parts, and random detail stuff. Some will get covered later when it seems appropriate, eg. parts collection, and some will likely vanish into the abyss as I didn't take the time to take pictures, like plating hardware. That involves some nasty acids and electricity so I wasn't too keen on taking off the PPE to work a camera.

So what's next? Hopefully something exciting but I am being attacked by a puppy with a broken foot right now, so we'll have to wait and see.

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14,241 Posts
Alan, my friend, there's no words. Once this beast is completed it'll be the finest built MKIII in existence. No question. 🍺

What's even more impressive is this is only the beginning, with so many other truly magnificent parts and details yet to be shown here.
This build thread is already epic, and it's just getting started, everybody! I can't wait for more!

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13,842 Posts
An EPIC, EPIC build!! I've been waiting for this, Alan. Thank you for this!


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Wow @Captain this is going to take some time to digest sir. Thanks a whole bunch. Really super awesome post.

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It's about time you put together a build thread, this was an excellent read. Impressive work on the targa brace, though I was fully expecting you to have painted it titanium blue for some odd reason :ROFLMAO:

A few things I picked up on your build that I might apply to my car, the battery box rubber (didn't think/know about that), and the various relay/fuse boxes you used, I saw at least 3 different ones. Where did you find those boxes?

Looking forward to more progress posts!

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14,241 Posts
I re-read some of this today over my lunch break, and I love the dry humor. It's like I'm talking to you in person. :)

To anyone who hasn't met @Captain, he's a funny bastard that has mastered sarcasm and dry humor to such a high art, that some folks who meet him for the first time seem to think he's being serious. It's always a good time 🍺

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13,842 Posts
I re-read some of this today over my lunch break, and I love the dry humor. It's like I'm talking to you in person. :)

To anyone who hasn't met @Captain, he's a funny bastard that has mastered sarcasm and dry humor to such a high art, that some folks who meet him for the first time seem to think he's being serious. It's always a good time 🍺
What he said. Alan's beard was always an active participant in those "Is he serious?" discussions 🙃.

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