hi. i have a 1986 351 h.o and i am putting on a set of c90e 69 heads. i need to know how much clearance there is when piston is at top dead centre to the deck. i f anyone knows this or has any hints for me it would be greatly appreciated. i am just getting ready to bring the heads to the machine shop to get done. thanks.
Well there's quite a few things that determine the deck clearance. Some cheaper rebuilder pistons have reduced compression height, there is manufacturing tolerance in original parts, etc. Since you will be replacing the heads, you will be able to measure the clearance directly when they are off. I would note each cylinder clearance, then you would see if one bank were higher than the other.