Thanks for clearing that up Tiny.
I checked all my 848 heads (7 of them) and all are 3836848, that includes 2 1956 date code heads. So it looks to me like 848 heads were used in 1956.
I am still pondering why the compression increase from 8.0 to 8.25 in 1958.
Is there a difference in the combustion chamber or did Chev change the way they measured them.
I will need to CC some heads.
