Great site, have enjoyed it for several months!  I have a pair of "G" heads from my '57 Fairlane; I suspect they may have been milled, how can I measure them to check.  Note to Ted Eaton, your dyno "mule" test should be interesting; I believe we are really finding out what makes these engines run, good luck!

Kanasy,

General head thickness check rule is that the 2 square pads on outer lower edge of head are .1000" thick or 1", any less is general guide to material having been removed. Note, i have come across a couple of heads that have been thicker than the normal .1000".  best regards bill.

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

Kansas Y;

I'm sure you will get many responses to this question with more accuracy that I will provide here, but I measure the rectangular bosses along the head surface that mates to the block. I've been told (somewhere by someone) that they need to be at least 1.000". I believe that a non-milled casting will be somewhere around 1.035", but this number probably varies with the particular head casting.

Rono

  Ron Lane,  Meridian, ID