truck-turbos have pretty wide powerband,plus they are of modern design! so if you choose one from a engine thats about doubble the size of your petrol engine, I can promise you some juice! lets take an example:
formula offroad car, mounted in a used 383 LS1-engine(sorry naming that) and fitted a turbo from a 14L scania, @ 0,9bar, thats about 12psi? he has 860hp. stock engine.
(i hope a picture of a chebby is ok!lol)