Here's the info: I'm rebuilding my motor with new forged (Mahle) pistons and new forged (Hawks Racing) H-beam rods. I got a 6.125" rod and the pistons are supposed to have an offset wrist pin location to compensate for the longer rod. The crank is stock (has only been polished) and the block has NOT been decked. When I put a couple of the piston/rod assemblies in the motor, I found that at TDC, the piston rises .008" ABOVE the deck. I haven't been able to find any info on the stock piston-deck clearance, but I'm almost positive that it's not going to be above the deck. Assuming the pistons are correct (I've cross-checked the part number engraved on the pistons; they should be right), what would cause the pistons to rise so high at TDC? Does anyone know what the factory clearance should be???

 

that is actually normal

i ahve my stock shortblock apart now and i noticed the same thing

i asked someone who knows and he said normal

 

Agreed, that is normal, and .008" sounds about right

 

.007 is stock so .008 is very nice. Now you need to find a gasket to give the best quench .038>.040

 

Obviuslly a .046-.048 compressed thickness gasket.

 

After putting in the rest of the rotating assembly, I noticed a couple other things. First, there is some variance in the over-the-deck height of the pistons. Average is .006"-.007" with a maximum of .008" and a minimum of .004". I know there is some tolerance in the deck flatness across the motor, so that may explain the variance there. The other thing I noticed is that the pistons all seem to be "leaning" towards the outside of the motor. For example, one piston is .004" over the deck at the top (closest to the valley) and FLUSH on the bottom. Is that normal?!?

 

ttt ?