I wanna know too. I called Eddy tech line a few months ago and ask them about them. The guy said with stock or stock replacement pistons the compression would be too low but the heads can be milled up to .050 but he thought .030 off would be enough. Said theres no way the heat riser could be added, I though maybe you could drill a 1/2 hole to get exhaust heat for the intake--going to be only around 30 degress all this week but no salt on the roads yet so its going out for sure--I am not 100% sure he was right, guess a good machinist would know. I also ask about if the cylinders have to be noched out for the 2.02 intake valves so the valves don't hit the cylinder walls. He said no work like that has to be done, just mill them and bolt them on. Now I have my lastest Summit Racing catlog and get this it has a * and under it it says 318's need to have the cylinder walls noched out for clearance!. Has anybody here use these heads on a 318?