GM PISTONS & RINGS

GM Performance Parts pistons are top quality and are ready for the rigors of high-performance street and competition applications. They’re factory tested, so you know you’re getting the right parts for your big-block engine. Pistons are sold individually unless otherwise specified. Available in standard and oversize diameters. Wrist pins included with all pistons. Part numbers are for one piston; order eight per engine.

GM Big Block Pistons
Part Engine Bore Oversize Rod Pin Compression Chamber Ring Description Number Size Size Length Type Ratio Size Size
10215228 454 4.250" — 6.135" Pressed 8.75:1 118cc 5/64, 5/64, 3/16" Forged Gen V & VI 454 HO replacement
12529559 454 4.250" +.030" 6.135" Pressed 8.75:1 118cc 5/64, 5/64, 3/16" Forged Gen V & VI 454 HO replacement
12533507 502 4.470" — 6.135" Pressed 8.75:1 118cc 5/64, 1/16, 3/16" Forged Gen V & VI 502 replacement
12533553 502 4.470" +.030" 6.135" Pressed 8.75:1 118cc 5/64, 1/16, 3/16" Forged Gen V & VI 502 replacement
6262976 454 4.250" — 6.135" Pressed 9.0:1 118cc 5/64, 5/64, 3/16" 1971 LS6 replacement
88962925 572 4.560" — 6.535" Floating 9.6:1 118cc 1/16, 1/16, 3/16" Forged 572/620
88963227 572 4.560" — 6.535" Floating 12.0:1 118cc 1/16, 1/16, 3/16" Forged 572/720R

GM Big Block Pistons Rings
Part Number Bore size Oversize Ring Thicknesses Description
12498734 4.250" — 5/64, 5/64, 3/16" Standard size ring pack for ZL1
12523921 4.250" — 5/64, 5/64, 3/16" Standard size ring pack for Gen V 454 HO
12523923 4.250" +.030" 5/64, 5/64, 3/16" Oversize ring pack for Gen V 454 HO
12524293 4.470" — 5/64, 1/16, 3/16" Standard size low-tension ring pack for all 502 engines
12524294 4.470" +.030" 5/64, 1/16, 3/16" Oversize low-tension ring pack for all 502 engines
12499212 4.560" — 1/16, 1/16, 3/16" Standard size ring pack for 572 engines
12499232 4.250" — — Set of 8 ring packs of P/N 12523921