318 heads on a 340 !!

[mopar1970]

I just picked up a 340 and it seems to run pretty good. But when i was putting new valve covers on it i decided to run the head numbers and discovered they are 318 head. Does anyone know the reason for this ???

 

[racedodge]

they are not the original heads or you did not decode the numbers correctly.

OR.. its a smogger 340 and they wanted to boost compression by putting on 318 heads.

 

[Cranky]

318 heads have smaller combustion chambers than 340 heads (like mentioned) but the diameter of the combustion chamber is much smaller than the 340 cylinder bore. Be careful the pistons don't strike the edges.....