Big Block Chevy 3963512 Block 4 Bolt Mains K 12 9 Fresh .030 Over
 

This is a very nice 3963512 4 bolt main engine block. This came to me out of an estate as a fresh built 427 shortblock. The engine had been a complete engine and after the man passed away, thieves broke in and stole a couple cars, and many parts, including the heads and induction off this engine. I don't know what the top end was but it must have been pretty stout based on how the shortblock was built. It had aluminum rods, head and main, studs, Summers Bros gear drive, and a Crane solid roller cam. Since the block is dated during 454 production and the internals were dusty, I decided to tear the short block down and sell the block by itself. The block was decked when it was built but I could see the factory CRV code indicating LS6 written on the back of the block before I painted it.

This block is in very good condition as shown. I see no breaks or repairs. The cylinders are bored 0.030 over and are awesome with no damage save for some light staining from the rings staying in the same positions for a long time. All threads are in good condition with no helicoils or thread inserts. The 1970 4 bolt main 512 blocks are very hard to find since the only production application that called for a 4 bolt main 4.25 bore block in 1970 was the LS6.


$3500

Thanks,

Jason

Here are some pictures of the shortblock before I tore it down for those curious.


Jason