Quote Originally Posted by 1JohnnyO
Pat, I dont know what heads, that's why I asked him to post the casting numbers. I agree, if they are the small ports, no way will they work. If they are large oval ports, the with a little work and bigger valves, they will be OK as long as Dusty isnt building an all out race engine. The bigger ports and valves will come to life at higher rpms, but in the event he's building a mostly street/HP engine, he doesnt have any real need for huge ports. That's all I was trying to get across. And as you said, you reach a point where the machine work isnt worth it, you can buy new better flowing heads for a little more.

Eric, we're not talking about stock heads...I did say 'with some work'. I know of many guys with over 500 inch blocks, and yes, they're drag racing, using GM iron heads, and they're running in the 10's....that isnt too shabby. I happen to have the 291 rect. port heads on mine, and I dont have any lack of air flow at any rpm that I have run so far. My cam's lift is .655/.663, and as I said, I only do them once a year. I dont have crazy spring pressures, and I dont believe Dusty is looking for that either. And I guess I dont quite understand your last sentence...I didnt do that with my engine, and Im not proposing that Dusty do that either. As I said in a previous post, 'no offense to Eric' If you are ticked because I disagree with you on the lash adjustment, I apologize! But dont twist all that I said into something else. John
Well Dusty it seems we have a bit of disagreement here.
I have not gone to the strip for a few years but I have a hard time believing that there are many guys with over 500 inch blocks drag racing running GM iron heads.
Back in the 80's maybe, but most of the guys that I knew that could afford 500+ cubes also could afford good aftermarket aluminum heads.