Question on OEM chevy heads

[DEMON44]

Are both heads always same casting number on engines?

Case...........went to make a trade with a guy for 336781 heads to get rid of the smogger 346236 heads. get there and 1 is a 781 head the other is a 6272292. guy says came off same engine!?!

 

[4X4HIGH]

Are both heads always same casting number on engines?

Case...........went to make a trade with a guy for 336781 heads to get rid of the smogger 346236 heads. get there and 1 is a 781 head the other is a 6272292. guy says came off same engine!?!

Yes the head casting numbers should always match.

 

[DEMON44]

ok thanks. thats what I figured but wasn't sure.

 

[toomany]

They should always match, but after years of being on the road things will get swapped. People think that just because they have another head, it's the same as the ones on their motor.

I've had motors where one side had a head with 76cc chambers and the other side was 58cc. Motor ran, but it wasn't the smoothest thing.

 

[DEMON44]

thanks guys. that is what I though.

Now would I be better off. keeping the crppy peanut port smogger 346236 heads on it OR getting some aluminum intake and putting the 2 large ovals with different castings. One is a 781 the other is a 2292. my brief reasearch into them I think they're the same chamber, port and valve sizes> any one know for sure?

thoughts>

 

[chulisohombre]

when i bought my truck it had a gm crate engine that had different cast heads on them.i would rather have the same cast numbers if possible.you would have to measure everything to be sure they are the same.from what i saw the 781 was from 73-85 and the 2292 is from 70-75.both are oval port and could interchange.what is the 3 digit number on them?that will give you the port size to see if they will match up.i got that info from here
http://www.joesantiquecars.com/Chevrolet-engine-block-casting-numbers.html

 

[4X4HIGH]

thanks guys. that is what I though.

Now would I be better off. keeping the crppy peanut port smogger 346236 heads on it OR getting some aluminum intake and putting the 2 large ovals with different castings. One is a 781 the other is a 2292. my brief reasearch into them I think they're the same chamber, port and valve sizes> any one know for sure?

thoughts>

If the casting number is different then there is something different about the heads. Do not mix casting numbers (that is a bad idea) for the reasopn i just said.