L78 396/375 HP Long Block CKO Stamping

**SuperNovaSS** · #1 05-01-2006, 09:08 AM

Look at Ratbirds CRR stamping. What about this being a 4 bolt main 290 block? hey are said to be 2 bolt only blocks but this is definitely a factory 4 bolt.

Jason

Jason

**Stefano** · #2 05-01-2006, 06:59 PM

[ QUOTE ]
Look at Ratbirds CRR stamping.

[/ QUOTE ]

Which Ratbird?

Also, I have seen the double stamp/ shadow stamp on other original non decked or restamped blocks.

**SuperNovaSS** · #3 05-01-2006, 07:50 PM

Thanks Mark! I felt like a lobster over here. I noticed that pad had the same 2GMEXXX stamping. Any idea what it could mean?

**PeteLeathersac** · #4 05-01-2006, 08:08 PM

And notice the 2 & GME & XXX are all on different angle/planes so have been done w/ 3 different hits....possibly at different stages of assy? .

~ Pete

**92646** · #5 05-02-2006, 01:50 AM

All I really knew about the motor is where it sat for almost 20 years. I thought it would make a real neat warranty replacement motor for a 1969 or 1970 car but it never got used. I sold it for my buddy about 3 years ago then last year I end up with a LA built SS396 Camaro that I think is a L/78 but with the wrong motor in the car. If Jason's motor came out of a boat and this one looks as if it was in a boat before it was put storage. Is it possible that these were installed when the boats were being manufactured? If I remember right Mercury marine used a LS6 crate motor later on in boats. And that might help explain the additional stampings on the pad. The motor I had did not look to have been apart and still had the factory GM / TRW pistons plus the hone marks in the cylinders.
Mark Sheppard

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