vortec heads

[eventhorizon66]

My understanding was that you're wanting to simply swap out heads on an otherwise stock goodwrench engine.  If that's the case, there is no need to worry about retainer-to-valve guide clearance.  Were you planning on a high performance cam as well?  If you swap cams, just limit your lift to about .460" and you should be fine.  While there is certainly merit in pursuing higher lift, keep in mind these heads were designed for strong low lift performance.

[Donut]

it appears that you have to do some head grinding prior to installing these heads even with the new ones you but from scoggin dickey according to the last article posted..im beginning to wonder if its really worth all the effort and a 1 thousand dollar bill just to gain 50 ponies...is all of this true?

You can purchase aftermarket, or some of the SD heads have already been re-worked by them (for .500+ lift).  On mine I did do a few of the retainers (ghetto grind) to maintain clearance, but I'm also running an aftermarket cam with I think has .465 lift.  The clearancing "may" not have been necessary, (it was that close) but I didn't want to take the chance once they were installed.

Also, just fyi.  My heads were a junkyard pull that had been checked for cracks, that's it (062 castings).  I think it was about 250.00 for the pair (complete).  I got them from a guy that knew a guy...  I did go back to the junkyard and get a pr of valvecovers.

In my case they were very worth the swap, and done on a budget.