I'm getting a 383 soon. It's gonna have a .515 .520 lift roller cam installed, HSR intake,and Headman shorty's. I already have a set of Vortec heads with upgraded .550 valve spring's. If I get a set of 1.6 rockers, am I gonna be pushing the limits of the spring's? I've also heard that unported Vortec's make most of their power under .500 lift. But if that were the case, then why would they offer them with spring's capable of .550 lift?

My goals with this motor are to get 400-425 streetable horses. As soon as I figure out which rocker arm's, pushrods, and fuel injector's I need.... The motor will be ordered. Thanks to anyone who can possibly help!

 

anybody???