More on Cracked Head

[Adrian Jones <AdrianJones@compuserve.com>]

Hi All,
I've obtained a TR4 head as a replacement for the cracked head on my TR3A.
Using a vernier caliper, it measures 3 and 5/16 plus 1/128", all around.
Should I get it "shaved" and if so how much.
I would like maximum power without the need for special fuel.
I was running on the "middle" fuel grade without any pinging before the
head blew - compression reading were 180 +/- 5 psi.  The cracked head, if I
remember right, measured pretty much standard, ie. no shaving had been done
on it.

Regards,  Adrian