Ive got a crate motor from a buddy of mine that he bought a few years ago for a Jeep conversion that he now wants to sell, but I cant find out what it is, he was told that it was 96 lt1, 300 HP, it has cast heads with the number 1255429, there is a block number of 10125327, and another number 6145. The guy that sold him this motor said it was a 4 bolt main, (we havent pulled the pan yet).
Any ideas??????

 

LT1s have a "327" cast into both sides and the front of the block (and maybe some more places). There is a little pad by the oil filter location that they put a VIN derivative on production cars, but I don't know what they use on a crate engine.

 

Easy enough to tell an LT-1 from the gear-driven water pump and optispark. I think they only came in a four-bolt version in the Corvette.

 

Not positive here, but I recall that all 'crate' motors[GM replacement LT1's ] are 4 bolt..