I purchased a used pair of vortec heads for a 5.7 swap into my 91 RS. I'm going to use a stock GM LT1 cam, .447/.459 lift specs. I don't want to spend a lot of money on modifying the heads but would like to know what options there are on valvesprings for the heads that will accomodate the LT1 cam. And also if the heads will need to be modified. I'd like to use GM springs but if there are any aftermarket springs that would be able to be swapped in that would be fine. I was considering the LT4 springs but I think the diameter is too large for the spring pockets.

 

the heads are probably ok as is. Its a stock cam and the lift is blow .460".

 

The Manley 22410-16 valve springs are a direct swap on the Vortec heads and work great. I've used them on my LT4 HOT cam engine with L98 heads and my dad used them with a ZZ9 cam on his Vortec heads. Best part is they are inexpensive at $75 from Summit/Jegs.