230 PONTIAC OHC6 HYPEREUTETIC PISTONS THAT ARE 53 GRAMS LIGHTER. AVAILABLE IN .030", .040, .060" AND .080 OVER THE FACTORY BORE OF 3 7/8" VALVE NOTCHES ARE .050" DEEPER TO ALLOW FOR A .025" STROKED CRANK, A SLIGHTLY HIGHER LIFT ON VALVE, AND A HEAD THAT HAS BEEN MILLED. TOP TWO RINGS ARE 5/64" THICK, OIL RING IS 3/16" THICK...RINGS AVAILABLE ANY WHERE INCLUDING FROM ME IN A COMPLETE REBUILD KIT. WILL NOT CLEAR 230 4V HEAD. DOME TOP WILL BE CLOSER TO 10 TO 1 WITH 230 1 V  HEAD. WEIGHTS ARE FOR .040" OVER PISTONS: FLAT TOP BADGER PISTON,TOTAL WEIGHT: 718 GRAMS, POP TOP KB PISTON, TOTAL WEIGHT: 665 GRAMS. CUT TO FIT INTAKE AND EXHAUST VALVE NOTCHES. PAY ATTENTION ON INSTALLATION. THAT ALONE PROBABLY BOOSTS THE COMP 1/4. POINT.  2 DVD OHC6 SET INCLUDED THAT PLAYS ON COMPUTER ONLY AND IS MPEG FORMAT. 230  PISTONS 30 40 60 80 OVER. 230  FLAT TOPS SHOULD GIVE ABOUT 10 TO 1COMP. USE DOME PISTON WITH 2301V HEAD OR 250 4V HEAD...SAME VALVES, SAME COMBUSTION CHAMBER SIZE. DOME TAKES OUT 7 CCs. IF YOU KNOW HOW TO FIGURE THAT AND ARE REAL BORED, GO FOR IT. I WILL POST IT HERE: 7/4/22:   Hello Richard, things proceed, maybe slowly but surely. Photo: looking forward to the head! By the way I did some measurements for the cr-calculator. With 60cc chamber, 4cc valve-relief, 6cc dome, 0.006 piston-deck-clearance and 0.045 head gasket thickness I get around 10.1 (calculator from Diamond-pistons), about 10.3 to 10.4 with  Butler/Summit calculators. Great!!! Let's see what the compression-tester reads. FROM A SATISFIED CUSTOMER IN GERMANY. 7/29/22 COMPRESSION READING IS 155 POUNDS BEFORE IT RAN FOR 230 POP TOP ON A 230 1 BARREL HEAD. BETTER THAN I HOPED. WHEN I ORDERED PISTONS, THERE WERE SO MANY SIZES AND STYLES THAT I ONLY HAD 4 OF SOME STYLES AND SIZES. THEY ARE NOT GOING FAST, BUT THEY ARE GOING! DONT BE DIS APOINTED!!!