I just got done with the Indy-X "prepped" from IMM. I wouldn't do it again. The heads fell way short of what was advertised. Personally myself and my car isnt super competitive in the nostalgic events I run. I wanted to run iron headed for the glory. Big mistake for me not to go with the W2's. If you're looking to be fast and keep the build frugal go with the Eddys. You can bolt them on as is and upgrade as your pocket allows. Me personally I dont like the look of aluminum heads on my cars. Aluminum heads to me look like Ching chang chevy heads on monte carlos with giant Dale Earnheart decals on the back. And to be honest looks to me are the reason I have a dozen mopars in my collection and only 4 Z-28's.