I got the pleasure yesterday of talking w/ the tech line and the warranty dept. what a bunch of f-ing idiots! I got a set of their heads and they set the springs at the wrong installed height ( 1.700 vs 1.800) so they go into coil bind at .475 lift. They told me on the tech line to bump the initial timing up 4 degrees to solve it and the warranty dept. told me I was stupid for not checking that on a set of heads that say on the box "just bolt-on and go"