Please fill us in on the engine. 350? Already the heads sound way too big and "matching" cam is????? Stock crank? If it's stock oem cast, there's going to be problems. Not to make you feel left out of the loop, there is too much info not being supplied. Please help the thread here by giving us more to go on and what it is you wish to accomplish. Everybody here is more than willing to help and all of them wish to give you the right advice to give you the best results.