You can get an estimate, not an exact figure by measuring the head
thickness. Get a micrometer or a good set of calipers. Measure the thickness
between the head/ block mating surface and the surface where the valve cover
mounts.
A thickness of 3.460" equates to a CR of about 8.5. A thickness of 3.375"
equates to a CR of about 10.25. On the other end of the scale, some of the
newer heads go up to 3.550" thick and I guess these would be the 7.5 CR
heads.
FIW, I tried to use the Kas manual to create a linear progression of head
thickness to CR. I couldn't get the far ends of the scale to work. This
would be a neat item to have, if someone more adept than I were to succeed.
Peter
'68 TR250
on 11/23/02 10:24 AM, Richard Seaton at rsh17@msn.com wrote:
> I have a 1969 TR6 which had the head shaved when rebuilt ,but I don't know how
> much was taken off 15 years ago. Is there a way to measure the thickness of
> the head and to come up with some sort of compression figures?
>
>
> TIA
>
> Richard Seaton
> RSH17@msn.com
> View My restoration @ (http://groups.msn.com/Richards69TR6Restoration)
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