Thanks, good to know.

Interesting question. I'd like to know the answer as well. My Cobalt compression ratio was 9.2:1 and it was pushing 21-22 PSI on 93 Octane.

Direct injection.

Also wasn't AP1 running 12.1:1? I see those car turbo w high boost and stock internal all the time.

Don was running 20 something PSI on his BRZ. Making 460ish whp...


On E85, of course, but still, don't underestimate this engine! I can only imagine what people will push on Forged Internals...

I think the direct injection and the talent of the ecu tuning community can compensate for quite a bit.

I for one am excited that I can hope for a bolt on turbo kit running relatively low boost to make 300WHP and still be reliable.

I wonder how high crawford will push the boost.

Thanks for answering. I started getting confused as to why people were asking this question when there are multiple turbos on this forum pushing more power than me.

Well, IMO first things first, we gotta get rid of this CEL issues people are having :bonk:

Would suck to drop a turbo on this car and then a month later, have the CEL issue. Don't see that going over well.

US FR-S/BRZ owner: I swear that this car came boosted from the factory! It's the JDM version :rolleyes:

According to Jalopnik, the fix now is simply an ECU Reflash for Cam Sprocket problem.

But we are getting Off Topic now...

Sorry :bonk:

Boosted FTW! :D

Very nicely done.....

To broadly answer the questions of how you run boost on an engine with 12.5:1 CR:
Learn to tune.

Compression ratio doesnt prevent boost from working, nor does it cause an engine to blow up fantastically.

To put it very simply, the amount of fuel and timing is what essentially keeps your engine from knocking and eventually exploding. Figure out how to safely and reliably supply the needed fuel while running an appropriate amount of timing, and like magic the engine makes a metric fuckton more power without blowing up.

Im not gonna sit here and say its easy -- it takes time and patience to learn how to modify the tune of an EFI vehicle safely and reliably -- but its not exactly rocket science either.

Well put. I remember seeing some notes from the guys tuning my car and on the "to-do" list was "Finish magical tune" haha.

The car really does feel different at different RPM's. At some points the tune is perfect and others it needs some fine tuning. They aren't finished with my car yet though. We are running Meth however and that helps with knock.

This is perfect. especially to get rid of those pesky Camaro's/Mustang's/Skittles around here trying to race everyone