the only reason a supercharger (instead of a turbo) normally would be used with a 9:1 compression engine is that a supercharger tends to make lower boost, and 9:1 is a bit high in most cases to run a high boost application

a quick search says a stock celica gt runs on 10:1 compression... so you're saying that TRD produces a supercharger that can't be installed on the car without a new set of pistons?

 

That TRD S/C is low enough boost that the stock compression ratio is fine. I'm pretty sure even the smaller (higher boost) snout pulley is fine with the stock c/r. If you lower your compression unnecessarily, you'll just lose power. This isn't an aftermarket, engineer-it-yourself kit, this is a bolt on kit made to work within the reliable limits of the stock engine so it can be warranteed.
Now bolt that bitch on and smile.

 

you need the special hood for trd supercharger and u might wana lower compression on pistons cause the celicas have high compression if ur gonna spend that much i would just convert it 6 spped and u will run high to mid 15s

 

god damn... this post is a month and a half old... let it die