When Chevrolet introduced the LS6, it was the most potent engine ever offered right off the showroom floor. After 25 years, the specific components comprising the LS6 have become somewhat shrouded in the overall mystique of the engine. Also, the innate value of these awesome A-bodies has caused more than a few bogus cars to surface. To help understand the specifics of the LS6 cars, here is a list of codes, casting numbers and components used in LS6s.
ENGINE ID SUFFIX DESCRIPTION
CRV 454hp, manual trans CRR 454hp, auto transCARB LIST # GM PART # APPLICATION
4557 3967477-GG Manual trans, 49-state 4491 3967479-GM Manual trans, CA emissions 4492 3969898-GR Auto trans, 49-state 4556 3969894-GP Auto trans, CA emissionsCOMPONENT CASTING # DESCRIPTION
Block 3963512 4-bolt main, cast iron, 4.250-inch bore, external oil cooler provisions Heads 3964291 Cast iron, rectangular port, closed chambers, 2.19/1.98-inch valves Intake 3963569 Aluminum low rise, rectangular port, Holley flange Exhaust manifold 3909879 Left-hand side, cast iron with AIR holes Exhaust manifold 3916178 Right-hand side, cast iron with AIR holes Crankshaft 3520 or 7416 Steel, cross-drilled, tufftrided, 4-inch stroke, external balance Pistons 3963550 Forged aluminum, 11.25:1 compression ratio, # on piston dome Camshaft 3863143 Solid lifter with 316-302 duration and 0.520-inch list Water pump 3931065 Cast iron, long-style Distributor 1111437 Aluminum housing, single point with vacuum and mechanical advance Alternator 1100837 37 amp, externally regulated, single deep groove pulley Starter 1108418 Manual transmission, high torque Starter 1108430 Automatic transmission, high torque Pulley 3995647-AP Water pump pulley, deep groove Pulley 3955291-AB Crankshaft pulley, deep groove Tachometer optional 5700 yellow line, 6500 red line, pale green markings (not white)