Thread: 67 engine block Identification help

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Hello,
I recently purchased a 67' chevy c10 with a l6 in it. I am having trouble identifying the engine though. The casting number is 3994256. Does anyone know what that is or anyone that would be able to help me out? Thanks,
jberesk

Check this out could be helfull to you

http://www.nastyz28.com/sbchevy/sblock.html

Casting numbers for GM engines and heads are not a positive indentifier. The casting number was the part number of the casting (duh). Then, that casting could be machined into one or more part numbers.....like heads with small valves and another part number with big valves. Also, the same casting number is usually used over several years.....and several models of vehicles.

There is a stamped number on the sixes just like there is on a V8. The six number is on a pad near the distributor if I remember correctly. In that stamping is a two or three letter combination that tells the year, vehicle style, and (usually) if the car was a stick or auto. The code on a V8 also tells the engine horsepower (carburetor) and if it is a solid lifter motor or not.

dont know the site with six identifiers.....used to be in the paper parts books at the Chebbie dealer but that's a long time ago.

I have the same cast id numbers on my
1974 GM 165 (inline 6 cyl)
Block GM 3994256
Mercury Serial Number 3355424
Carburetor GM Rochester 2Jet 2GC 7042183
Solenoid 25661
Alternator 1101937 (1107937) 63A
3B8 12V NEG