Help Decoding Engine Block
 

I need help decoding a replacement block. The block casting number is "3963512". The stamped date code is "C2670". Also, "CEO A" is stamped on the front pad. Current owner thinks it is a 454, 4 bolt main block. Would this be a COPO resplacement block?

Re: Help Decoding Engine Block
 

KXW;

I see no one else answered this so I will try. The is a CE block so it could be one of many configurations. Looks like it was stamped in 70 so it could be a replacement for the 69 427 COPO BUT it could also be a 454. This casting was used for both 4 bolt and 2 bolt mains and many different HP applications including trucks. I do not have a listing for the CE configurations.

I hope this helps.
Greg

Re: Help Decoding Engine Block
 

The 512 casting would be correct for either a 427 or 454. The blocks are the same so you would need to check the crank to know for certain, just as Greg Stated.

The C 26 70 would pertain to March 26th ,1970.

The CEO translates to: Chevrolet Engine 1970

Due to the early casting date in 1970 I would guestimate that it was an L72 427 Block if it has 4 bolt mains.

Re: Help Decoding Engine Block
 

<font color="red"> A engine coded with CE is a service parts engine (Chevrolet Engine, CT would be Chevrolet Trans etc). It could have been installed under warrranty, or sold to someone over the counter.

If it was warranty then in all probablity it was just a short block, all the other original parts would have been reused from the defective engine.

A short block was just fitted block with pistons, bearings, cam and timing gears. The oil pan, dist, water pump, intake and carb, valve covers would have been reused if serviceable. The CE prefix was used for partial engines and well as complete engine assemblies.</font color>

Re: Help Decoding Engine Block
 

Even a warranty replacement could have been just a short block. GM would replace only the broken parts not the complete engine.