Need a little help and some add-vice.

[TJ's Chevy]

Ok...So alot of you guys know about my 64 C-20 I got awhile ago. 292 I6 with 4 speed....there is a mystery to remain...Is it the original engine..or is it a crate engine. It originally was a 3 speed column shift and someone changed it to an SM465...the 292 had some stuff done to it...painted blue...head gasket change out to felpro blue. I'm not sure if anything else was done...heck...the engine coulda been rebuilt. One member here warned me about a possible .030 overbore done to it....So my question is...is there a way to tell if that was the original engine? Here are the numbers.

Conveyor belt 2. C24 4 3 AM/PM 3851659 GM
5

As much as an I6 guru as I am I've never actually taken it to consideration that this engine coulda been rebuilt or had mods done to it before I got it...its obvious the engine was either pulled and painted...or bought as a crate engine and painted. but, I don't know fer sure....I'm planing on hot rodding this engine and want to bore it .040 over. Is there any way to tell if the engine has been bored over in the past with out having a machinist measure it? lol I'm gonna have him do that anyhow...but just curious. Thanks guys.

[AcampoDave]

Tj...many non standard pistons will have their overbore size stamped on the top. Unfortunately you gotta pull the head and clean the carbon off the piston top to see it.

[66Submarine]

Originally Posted by T.J. MCCAULEY

head gasket change out to felpro blue. I'm not sure if anything else was done...heck...the engine coulda been rebuilt. One member here warned me about a possible .030 overbore done to it....

Hey, I think I might know that guy!

The block casting number 3851659 is listed at the inliners site as '63-'76.

C 24 4 is the date code; March 24, ***4; so it's a '64 or '74 block.

Given the truck is a '64 and the rest of the stuff bolted to the block looks correct for '64, I'd say that's what it is.

So, my guess is it's the factory-installed engine that was pulled out and worked on/repainted at some point.

[66Submarine]

About the overbore; do you have a good machinist's type ruler/scale? 1/32" is .03125, so the common .030 will be pretty much 3-7/8"+1/32"; if it's standard it will be 3-7/8" (obviously), so anything over that = overbore.

[1963c-10]

Engine suffix # will tell you if its a crate engine.

[TJ's Chevy]

Thanks all....I was actually thinking the head may have been pulled to replace a blow head gasket....PO told me his father wasn't..ahem...the best driver either. lol Guess they used to rev the snot outta it....I think the engine may have been pulled when the tranny was changed out. Far as I know the PO's father bought the truck used....so I'm not sure what it was like when he bought it. PO's father passed away ages ago...anyway...I'm a gonna look at the pistons an see if they have the over bore stamped on them..if it was..Its funny...this engine was made 15 days earlier then my b-day. lol

[TJ's Chevy]

Originally Posted by 1963c-10

Engine suffix # will tell you if its a crate engine.

Where's that located?

[1963c-10]

Near distributor, above fuel pump and stamped into block. Should be something similar to this suffix code F1010UH .....f is flint, the numeric is the date code and the suffix is UH which tells engine hp/and sometimes what trans was mated. Can be helpful on narrowing down the assembly date and maybe application. The section in blue and underlines is what we're looking for.

Sometimes there are 3 letters in the suffix and not two....

[66Submarine]

To clarify, it's stamped into the distributor mounting pad directly behind the distributor; you can see it in this picture of one of my 250's.

[1963c-10]

Thanks...66Submarine

[TJ's Chevy]

I be sure to check.