Originally Posted by yar
Jim,

Here's a discussion on Chevy Talk that says compression on a '54 235 is just under 125#.

http://www.chevytalk.org/fusionbb/showtopic.php?tid/282437/

So low 80s# on that '48 engine might be a clue.

The Shop Manual shows we should hope for 130 or better
(I am happy with 125 or better).