Originally Posted by BLM

I'm more interested in the bolded part. Just curious, when you say upper gear do you mean 1-2? I think "lower" for those. With all the market competition and choices in terms of forced induction, I was always wondering what the stock trans and engine internals could handle. Coming from a wrx that made 375 whp on stock internals and nothing but an aftermarket clutch, I never ripped it through first gear and was always just waiting for things to break. Granted, the internals and trans are different from car to car, but guys putting down much less power than I were ripping up first and second gear.

The guys at Performance Motorsports suggested that a conservative estimate for the stock internals was 450 whp for a daily driver, but also added that as you approach 500, you're pushing it. It seems that a 6.5 psi kit making 400 whp would be the perfect mix of a huge bump in power over stock while maintaining reliability and drivability, until of course I saw this post. I know this has much to do with driving style, but has anyone else reported/read of issues with stock internals/transmission? After all, what's the point in spending the time and money for all this crazy power if you have to baby the car? If I had the cash I'd go all out and build the motor and the trans first, this way you can use the full potential of these SC and TT kits and not worry about blowing motors or gearboxes.

Also, shumby, did you have an aftermarket clutch when you damaged the trans? And what exactly did you mean by your "driving style". Even with 500 whp the gears wont just shred up under a load. They would be most vulnerable to hard launches with a strong clutch and aggressive shifts.