Steve---The pressures that you've indicated for your '72 are a bit
higher than what is generally agreed is "normal" for an engine with the
7.75:1 compressure ratio. Interestingly enough, these are about 5 lb.
more than mine, that also shares this C.R. Be happy with these numbers
and the good balance between the cyl. readings. The only things that I
can add to this would be that maybe a previous owner has had the head
shaved, perhaps to "clean it up" before regasketing and the new ratio is
now closer to 8.0:1. Be sure also that the engine is fully warmed
before taking this check, as thick oil can add a few numbers on the
gauge.
I have no idea how the "19.7" number became part of any formula to
arrive at a PSI. Listers??
Dck T.
'73
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