[92646]

It is the much improved later casting. Neat car, here is the description of the motor from the -e-bay ad:

Motor:

New ZL-1 block casting 3946053 aluminum

Intake: Original ZL-1 casting 3933198 aluminum

Heads: Original rebuilt ZL-1 casting 3946074 aluminum

Carburetor: Original restored by Holley ZL-1 3955205 4296

Original NOS GM 3959180 ZL-1 cam and NOS GM 5232695 solid lifters. NOTHING sounds or runs like a real ZL-1 cam. Cam specs: lift 580"/620", duration 354/360 duration at 050" 262/273. L-88 .030" over pistons combined with 122cc combustion chambers make 11:1 compression, and with this cam duration there is no problem using 91 octane pump gas. Original NOS GM ZL-1 casting 7115 crankshaft. Original NOS GM 3969804 rods. Original NOS GM ZL-1 7/16" 39424165/3942416 pushrods, Original NOS GM ZL-1 3959182 H stamped rockers, Original NOS ZL-1 oil pump 3969670 and brazed pickup 3955281. Correct NOS GM oil pan. Correct Original timing cover (A-O-R angle), NOS GM timing chain set (not the plastic gear one, the GM double roller one: cam sprocket 3891517, crank sprocket 3891518, timing chain 3891519, Impossible to find now) NOS GM 8" correct 3879623 harmonic balancer. ZL-1 repro fuel pump AC 40731. Correct for ZL-1 black painted engine parts.

Complete Original GM ZL-1 correct Transistorized Ignition system: Original restored T.I. distributor 1111927 with original tag, NOS harness 6297688, NOS amp 1115343, plate, all installed per factory instruction blueprints. Vacuum advance added for excellent driveability.