Mainevent....
The "vortec" aluminum heads on Ebay are not Chevrolet-made heads and dont appear to be Vortec.....they dont have the Vortec bolt pattern on the intake....nor are they "pro-race" heads......I doubt any racer that is a "pro" would use stuff like this. Yes, they are cheap aluminum heads. Yes, they will fit a Chevy small block....but their ad is pretty much all hype.

Chevrolet calls their Vortec-derived aluminum heads "Fast Burn" and they sell for somewhere in the $1100 range complete.