Indy's customer service is non existant, although I spoke to a newer employee Sam at Carlisle and he was decent to talk to. At least he didn't treat me like a lower life form which is std operating procedure. Indy heads need the same stuff Edelbrock, 440Source, MP, Brodix, etc all need. They need to be checked and the valve jobs corrected. The last set of Indy's I had in hand needed seats recut (out of round by .009" in one case) and several tight guides. In an older se tof SRs I had a 1/4" aluminum shaving stuck in teh assembly lube in one intake port... OOTB is not the way to exploit any of these heads. My advice would be t find a good ICH vendor and deal with them. Bob George Racing in PA and Porter Racing Heads in VT, Muscle Motors in MI, Modern Cylinder Head in MI... Those guys will ster you right. The heads flat out work. but like anything else, need some tweaking to be ready to install.