LA edelbrock performer heads. Ported pretty much as far as we could . About 72cc combustion chamber. I will have to go back to the shop to find the flow on what the heads actually flowed at. I didn't get a print out of it from them. 2.08 intake valves. 1.60exhaust. Ported matched a victor intake to the heads. Custom ground cam by IMM. .683 / .657 lift. 260/266 duration. Lobe separation at 112 deg. T&D 1.65:1 rocker arms. I can't take credit for this build and all it's complicated parts. I read a car craft magazine that did a real good article on IMM engines and the mean little small block they built. We tried to keep it as close to their numbers as possible to keep it on pump gas. Although we did run into some problems around the lifter oil gallery. There was so much lift that it was bypassing oil to pan on some of the lifters. Had to machine out the block, re sleeve and change the lifter oil gallery to get full oil to the mains. It's a good thing we have a real good builder in my area to build this thing and figure out why oil pressure dropped on the dyno.