Hi there,
My engine ready to go in shortly.
I am sure it is a 394 as that is what I ordered however I have been questioned over this I know my builder knows his stuff. I have someone telling me it is a 371 as they
think they are 371 heads also a 394 apparently has 3 bolts on the center exhaust ports (2 top and one bottom) instead of 2, 1 top and 1 bottom.

Definitely a 394 as I can see it as there is ‘4-1/8’ is cast indicating bore size.

Also '59-'60 394 heads had two bolt holes on the center exhaust port, while the '61-'64 heads had three and took different manifolds, is this correct?

Could people in the know please clarify this is there a similarity between the 2 engines in this respect and has someone here got their wires crossed.

Thank you
John.

 

John, to clear things a little, 1957-58 had a "371" that was a different block and heads. 1959-60 had a 371/394.
You are correct about 394 because the 4 1/8 is cast on the rear of the block. Charlie Jones can tell you what heads they are. I think they are 59-60 heads (371/394) because:
1. they are #18 heads, (1957 heads were #14 and 1958 were #16 heads)
2. they have bolts in the flange of the valve cover (1957-58 had two bolts in the middle of the valve cover) .

 

Yes , you are correct .
That " someone " was wrong .

 

Thank you OLDSter Ralph and Charlie Jones for clearing that up.
regards
John.