273 302 318 340 build

Don't take that data from Summit...I have found plenty of errors on their data.

Stock weight is 592 gr and the pin is 161 gr.

If you are not running hard, I would go up to 5 grams if I was not caring, but I'd like closer. Google 'piston weight change for rebalance' and you will get answers higher than that.

It is not hard to drill some material out of the underside of the pin bosses to get them close to what you had. Or, since the pin walls are REALLY thick on these pins, just drill or grind some material out evenly through the pin's interior length.

You're not going to get a quench effect with any of these pistons....! Piston to head clearance is around .110" with the .028" head gasket and the taller 526 pistons.


You're getting there on CR IMHO! I am getting around 9.2 Static CR with:
- 302 heads milled .030", assuming the chambers are 64 cc's to start with before milling
- .028" head gasket
- The Sealed Power 526 AP pistons. These are around .077" in the hole and are the tallest stock type pistons around these days.