So I've been tossing the idea around for a while now about building a turbo motor for my AW11. Right now I have the blacktop 20v installed with the C52 5spd and I want moar powah. I bought a Manon Racing Products turbo inlet plenum to replace the factory airbox, and will probably be going back to him to get a custom tubular turbo manifold later. I don't have any particular power goals in mind, but something over 250 would sure be great! I plan on using it for mostly street driving and the occasional auto-x, hill climb or track day.
Right now I know I want to run the 20v head with the ITB's and the custom turbo plenum. What I don't know is everything else. I have a 7A block sitting in my garage right now which I was thinking of building up, or possibly buying an 8.9:1 GZE block and using that instead. I know the extra .2L displacement would be nice but the GZE block would be a simpler affair. Also I'm not sure how much the machine work would cost on installing forged pistons and rods into the 7A, as well as any other machine work that may be necessary. So, pros and cons of GZE vs. 7A?
Also thinking about which turbo to run. I'm very intrigued by Garrett's new GTX series of turbos. They seem to spool quicker than the older GT series in the tests I've looked at. Whereas I would've only considered something as large as a GT2860RS before, I'm wondering if I could utilize a GTX3071R to make more power without having too too much lag? I was hoping the efficiency of the 20v would be enough to flow that turbo without it being a peaky powerband. And should I run external wastegate (plumbed into exhaust, not dumped to atmosphere) or internal?
Next, I'm not sure which standalone EMS would be in my best interest. A lot of DIY'ers praise MegaSquirt up and down, but I know nothing about it other than it's the least expensive option. I don't want to entrust this potentially complicated setup to an inadequate EMS. There are several tuners in my area so I'm sure I can find someone to tune whatever I end up with. What works best for you guys?
Lastly, fuel and ignition system: I have an '04 STi fuel pump in my car now; I think it flows 190lph. Would I need to upgrade, and what size fuel injectors would be good - 440, 550, 720, more? I was thinking of switching from distributor and single coil to 1ZZ-FE coils. Sound OK?
Extra-lastly, has anyone made decent power on a C-series and lived to tell about it? I'm wondering at what point I can expect to blow it up. Would love to not have to get an E-series but if it's necessary, it's necessary.
Right now just looking for thoughts and feedback. I've seen a lot of low-budget builds under 200hp and some big-dollar builds over 400hp. I'm sort of looking to be in between - not too cheap but not too expensive, either. Help is appreciated!
1987 Toyota MR2 hardtop
20v blacktop 4A-GE
Ground control, Koni, Cusco, ST
XXR, Toyo, Wilwood, EBC, Odyssey
Recaro, MOMO, Fidanza, SPEC