MagneticZ51

iTrader: (21)

I was wondering if i could pick your brain. About all lsx based heads. Lets say AFR 225's. I understand that a 72cc head will lower a engine CR. Where a 60cc head will raise the CR on a motor. My question is on a 72cc vs a 60cc head. Is the valve height the same between lets say the exhaust valve at fully closed to the matting surface of the head? Which would mean the only difference between a 72cc and a 60cc is the contour of the dome of the head? Or do you take a 72 cc head and mill it down to a 60cc? Which would mean the contour of the dome of the head stays the same between the two. Im just trying to understand the the difference between the two heads on theses aspects.

Sales2@Texas-speed

iTrader: (5)

In most cases, a 72cc head and a 60cc head have different chambers cut into them to achieve those chamber volumes. Now, in some cases, people do mill a 72cc chamber head down that far, but you run into intake alignment issues and such when you do that.