jmalave1

Hello all,
I'm putting a GM crate motor into my 1986 corvette, and I bought the motor from a person who identified it as a GM ZZ4 crate motor. However, the engine ID is different than a ZZ4. The engine ID is VF 196027. Can anyone tell me about the history of this engine? I'm trying to figure out the cam specs and bore so I can re-flash my PROM. I'd prefer not to take it apart, as this engine was never used. I called Speedway Motors, and they think it's a version of a GM 604. I have no issues using a 604, as this is going to be a show car and I've put a much better cooling system into the corvette and I ordered a custom TPI system from First TPI which is being built for the fast burn heads in the motor.

Thanks,
Joe

Steves LS6

I am 99.9999% sure that GM doesn't build the ZZ4 anymore.

jmalave1

Yes, thank you. I know the block was cast in 2010, is a four bolt main, with one rear main seal, based on the block code. However, the engine id is still the mystery.

Kevova

There is some info stating ZZ4 is stamped on pad. There is another stamping beneath #4 & #6 exhaust ports. It may id engine. It may require valve cover and pan removal to id components then compare what you to GMPP Component Chart to know what you have