I switched wastegate springs at the track and pinched the diaphram when reassembling it. It went like a scalded cat until it ran out of fuel system at about 1,000' or so. The telltale said it made 18 psi somewhere along the way. It blew a hole about the size of a quarter in the top of #5 piston and actually melted the center of #3 as well. That was not the piston's fault, and I wouldn't have expected any piston to hold up to that abuse. (lean) I only replaced 3 of the pistons. The rest looked fine. I just had them balanced to the rest of the pistons' weights and back together again.

With my block decked - the pistons are .006" out of the hole, so I am running a .051" thick Cometic to get the quench down to .045". These EQ heads are supposed to be 62CCs but I measured 66CCs after I reshaped them some. I guess I'm running at 9.2:1 after running the numbers.

I'm running Total Seal Conventional Classic Steel Top piston rings. CS3690-35 Stainless Steel top ring, with cast iron second. Both 1/16" with a standard 3/16 oil ring.