Hi,Peter---If your goal is to build a moderately high (150) h.p. motor,
then you may want to take the head down to the thickness that Kastner
specifies. If you do the head without the proper cam and carburetion to
go with it, the results of going this high with compression probably
won't be to your satisfaction. The use of a performance cam bleeds off
some of this compression, and more fuel and air compliments both the
raise in compression and the longer duration of the 'new' cam. Raising
the compression to 10.0:1 alone will give some increase in performance,
but will put you on the verge of detonation, unless ignition timing is
greatly retarded, which cancels out some of the gains your looking for.
What I'd suggest you do is this--See how close you are to detonation
(heavy pinging) with the compression you are now running. You can tell
by going to 87 octane fuel, or advancing the timing about 5 degrees. If
either one of the two causes pinging, don't mill the head more than .040
from where you're at, unless you're prepared for big trade-offs in the
proverbial bang-for-the-buck.
Dick Taylor
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