I don't believe so. I do know that the machine shop had to sleeve the pushrod holes on the intake side with a thin copper or brass sleeve because when the heads were torqued to the block he noticed the intake port flex along the pushrod hole. He was afraid that if not sleeved that it may crack and cause a vacuum leak. Now if this was because of intake port work or pushrod hole clearancing, I do not know. It was 5 years ago. I have not had any issues with the heads at all since that time.Did you have to massage the heads to fit 3/8" pushrods?