The job otherwise went smoothly, I just think we didn't take the time to tie up enough loose ends before trying to take the last steps. The 5SFE engine turned out to have a header crack and exhaust blown gasket, and it made the car roar like it was cool. While the noise is nice, it attracted the wrong kind of person to the car (mostly idiots with honda civics and Folgers Mufflers). Since the headers were a write off, we didn't treat the engine too well and just tossed it in the corner. With the one open exhaust header though, the car sounded like it had a V8.
Part of the problem was that we didn't clearly tie off the ABS connectors. The new MR2 doesn't have ABS. This mostly just gets in the way of a sportscar because the brakes are going to be grippy as hell but also because the ABS sees the wheel hop when driving aggressively and retards the brakes. There's a road near where I live which has an S turn on it down a hill. The first curve is banked correctly but the second curve is reverse banked. There isn't a rusted piece of guardrail next to it since people constantly buy this curve if they're not familiar with the road. The side of it looks like a museum of abandoned body work. The only thing that saves it is that you can drift into the oncoming lane if you screw up and hopefully live through the experience. The red MR2 with ABS used to not be able to take this turn at speed. The suspension would compress through the turn and then the hop exiting the first turn would kick in the ABS. The white MR2 can do it at speed, which sold me on the idea that ABS isn't nearly as good as learning to actually drive the damned car. It's nice to have in an emergency, but general driving shouldn't include emergencies. When the ABS wants to be part of general driving, the ABS needs to go. Since I don't want the extra mass of the ABS wheelhubs anyway, that trash took a walk. The point of this is that we didn't mark the ABS plugs, so we spent a lot of time playing the "does this really plug in anywhere" game. To add insult to injury, the red MR2 had the 1991 "premium" (premium always means "gets in the way") sound system. More plugs on the main harness.
One of the other problems was welding up the exhaust. Jim is a good welder, but by the time we got started welding we had a few drinks and it slowed us down enough that the pace got screwed up. Slow welding means cold joints and things like coking up the tip. Three tips later... Well, it has a greddy exhaust with 3 inch pipes on it (including downpipe) but it was a reach. I broke one of the freshly welded studs off also, so it's just got a c-clamp on there.
The giant intake system (also three inches) had fitment problems. I bought a nice greddy-core intercooler from my buddy but the tubing kit that went along with it was crap and didn't fit. It was also missing one of the hoses, which by 1am Monday morning working with a flashlight, makes an interesting choice between "take the intercooler out" and "make the fucking pipes fit". We chose the latter and I cut up some hose apparently from an audi or something and managed to replace the missing section. I'm told that this is typical of the kit, which means I can look forward to dying horribly when the kit gives up under boost from it's crap-ass quality control.
Finally at 1am Monday morning, we got to the point where we were ready to coolant purge and fire the engine for the first time. We get all the lines hooked up and fill them with antifreeze (the idea is that the extra tubing serves as a reservoir for coolant until the bubbles flow up the tubes and the coolant gets sucked in). We fired the engine and did the coolant purge. Thinking we were home free, we went to take it for a test drive and...
Nothing. The car makes no power. It dies pulling down the driveway. We half expected it to be disagreeable until it soaked out the crap and got the air out of the fuel system, but after a 15 minute idle it's still billowing smoke and hard to start. I was starting to suspect that there was a problem with the fuel pump (replaced with one from a Toyota Supra - bench pressing a gas tank is an adventure) but Trav suggested timing. We had triple checked the timing since this is really hard to check with the engine in the car (think: "mirror on a stick") and then checked it again with the timing strobe. It was 10 degrees off.
Thankfully we all had time off. Jim is retired. Trav is just a really good guy and was willing to take off. I didn't have a choice since this is my daily driver. I slept over Travs and rolled around on his sofa with his cats to make disgusting greasy cat hairballs all over the thing. The cats thought I was great since I still stank after a shower. We drove back to the Secret MR2 Lab and rechecked the book. Oh did I mention we can't read? The book says the timing strobe will be 10 degrees off and must be corrected for with the diagnostic port when checking the engine. Sure enough Trav caught it, jammed a paperclip in the data port and the timing lined up almost to perfect. The way the strobe works is that the wheel riding the crank has a mark on it. The plastic covers have a mark on them for 0, -10, +10, and Explosion. The strobe fires when the first cyl fires which should be top dead center (0 degrees). Persistence of Vision means that you can see the normally flying mark clearly when the strobe fires.
Sure enough, we detected that the engine was close, but because I had gone over to a new big intercooler, three inch intake with giant stupid cone filter and three inch exhaust, a little off turns into a big off with a lot more air moving around. We loosened the adjustment pivot on the cap and rotor and lined it back up. Tightening it down became a pain since literally a hair off ruined things again, so Trav was kind enough to keep the strobe on while I bullshitted around with the rotor. The car could probably stand to use a set of plugs also after burning out all the grease and moly.
The free flowing exhaust and intake is worth a lot to a turbocharged car. I don't believe in headers, but I do think that the intake contributes a good bit and the exhaust makes up the rest.
The NA brakes are better than the turbo brakes. This isn't obvious but the turbo brakes are dual-piston and seem to respond less quickly than the NA brakes. More smashing surface means the brakes grip better but take longer to do it. I opted to keep the NA brakes. Bleeding the brakes makes all the difference in the world, I can't even crush the pedal to the floor. The clutch also makes a world of difference. The 130K clutch that came with the car was done and the pedal itself had really terrible fluid in it. Replacing the fluid and bleeding it corrected a myriad of problems in addition to making the clutch and brakes stupidly grippy.
Buy brass shift bushings. Solid shift bushings are worth their weight in gold, and Ron Paul approves of the gold standard.
The part everyone has been waiting for... The car makes 10 PSI of boost instantly and then starts to creep. The stock system wastegate is set to 10 PSI so the fact that the boost creeps past this means that there's more than enough intake and exhaust for this setup. I am not pushing the limits of this until the first oil change at 1k miles to get all the crap and dirt out, but even in casual driving this happens. Since the fuel-cut happens at 11 PSI which would be a serious overboost for the stock engine (which runs about 8 PSI), its running things damn close. Also the stock turbo can make up to 16 PSI before all efficiency loss, so I may next spring look to adjusting the fuel-cut and tuning the turbo to 14 PSI or so before dyno'ing it. No sense in being greedy, but every PSI is worth roughly 10 HP, so there's another 40 or 50 HP to be had out of the system. There's awesome power to be made here, but I would like to own a beater before trying to deal with every day situations like "how much grip do I have in the rain"? 300 something horsepower on a 2500 lbs car makes a power to weight ratio of .12, which is no longer daily-driver category.
Conclusion: Buy a horse. It's simpler.