Casting Number / Engine Size

[Chad7598]

I recently bought a motor and I was told it was either a 283 or a 327 out of approximately a 1965 Vette. I've researched all the numbers I've found on the motor and all I can tell is that it might be a 327 or a 350 from the late 60's or early 70's. The main things I want to know is what year it is, what vehicle it was originally made for and what size it is (283, 327 or a 350)? ... Mainly the size though. Below I'm listing all of the number and places I've found them and see if anyone can decipher them for me. I wrote down the numbers as closely to what the appeared to be as possible. I believe these letters/numbers were on the front of the block. C4F415069 V03061JC I think these letters/numbers were on the top of the manifold 340234 R B274 These letters/numbers are on the back of the block GM21 3970010 These letters/numbers are on the exhaust manifold GM336710 These letters/numbers are on the block inside of where the bell housing mounts to the block. 010 020 509 H18 PS78 2 7/64

[mr.beachcomber]

Originally Posted by Chad7598

...I believe these letters/numbers were on the front of the block.
C4F415069
V03061JC

Can't help with the first number, but its' not a Corvette VIN. The second number identifies the block as a Flint, MI (V) engine built on March 6th (03, 06) with a vehicle application code of "1JC". (Couldn't fine that one anywhere.)

...These letters/numbers are on the back of the block
GM21
3970010

The later number is the block number per se. In 1968 only, it was used for 327 engines while from 1969-1979, it was used for 350 engines in cars and trucks. I'm guessing you have a truck block from 1974. (Based upon the date code for the intake manifold which may or may not be original.)

...These letters/numbers are on the block inside of where the bell housing mounts to the block.
010
020...

The first number indicates that the cast iron block has a content of 1% tin while the second number indicates a content of 2% nickel. I'm guessing that you have a 4-bolt main truck engine just because I haven't ever seen a 2-bolt main with both extra tin and nickel.

Here's site to a site with info on how to locate and read Chevy engine codes that might help. Good luck with your new engine!

[INMYBLOOD]

http://www.nastyz28.com/chevy-engine-code-stampings.php

Look here. about half way down the page they get into the letters I just checked a block I have 3970014 T0501CNJ and the CNJ code was there.
My heads 3947041 High horse heads.... This is for sale as I am building another 350.

[Chad7598]

Thanks for the info. I cleaned the engine more today and realized one of my letters were wrong. It was the one from the front of the head. I originally put V03061JC but the correct numbers/letters are: V0306TJC

[mr.beachcomber]

Originally Posted by Chad7598

...one of my letters were wrong...I originally put V03061JC but the correct numbers/letters are: V0306TJC

Using the link provided by INMYBLOOD, the "TJC" code translates to a 1973 4-bolt main 350.

[warriorp]

010 casting block is a 350

[JMS71VETTE]

The GM code site I use shows this as a 1973 350, 160 base HP,4bbl,conventional cab C20-3500 Chev truck.http://www.nastyz28.com/chevy-engine-code-stampings.php