What can an 89 TPI 305 engine be pushed to, while still retaining everyday driver reliability? And what about a 95 LT-1? I'm talking just the engines, not effects on the trans, rear, etc...I understannd that basicallly every increase in power makes it less reliable, but I'm just looking for a decent estimate. Thanks.

 

Since no one has replied and there are no immediate plans for the LT-1, I'm going to focus on what's most important What can you get out of a TPI 305 without wrecking the stock bottom end?

 

The crankshaft is a cast unit, not forged. So that should limit the Hp. Off the top of my head I vaguely remember that cast cranks are good for about 350 Hp and about 5,500 RPM, reliable.

Do a search on this point, I know that this has been discussed here before.