You can definately make some good power with the LT1. My good friend Dan has a 385 stroker with LE heads and Bret Bauer cam. We took it to Big Shot Dyno in Ohio where it made 440 hp @ the wheels, uncorrected. Here is the link to his thread:
http://web.camaross.com/forums/showthread.php?t=449166
The car is an animal on the street! I don't want to give his specs away, but you could probably contact him about it.
Good luck with the rest of your build!