Originally Posted by SonicGSR98
They overlook one major thing is that article...the HF pistons only have Eight valves, meaning that the pistons only have two reliefs per piston. I had the chance to do this sort of swap and it won't work, you need to have four relifs per piston to throw a 16 valve head on the block. :af:
I've heard the same thing, valves will hit pistons since there are no reliefs.