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>From: sjw06@uow.edu.au (Simmo)
>
>I Am just building an 1835 for my 67 Notch an am up to setting the deck
>height using shims so as to obtain a compression ratio that wont blow my
>heads off but will give me plenty of power.
>
>Standard 1600 engines had a ratio of 7.5 : 1 and the 1500s had 8.5 : 1 as
>far as I know.
>
>I am thinking of going for around 8.0 : 1 for mine. It will be a daily
>driver so I want it to run cool but, ofcourse, I want as much power I can
>get out of it as I can.
The compression ratio you can get away with depends on many things, but
among those the octane of the gasoline you can buy stands out. I find the
many things that Gene Berg wrote about this were very level-headed. There
is really very little point in building yourself a car that requires very
special, very expensive gasoline to operate unless it's a race car and not a
street car. Gene also spent a lot of time figuring out how to get similar
power out of a low compression engine.
There were both high and low compression versions of the 1500 and 1600 carb
engines. Early (68-71?, U- prefix) FI engines had 7.7:1 compression and
later ones (?72-73, X- prefix) were 7.3:1. This was at the time when
octane was slowly declining, but still in the mid 90s.
Depending on the octane
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Melissa Kepner Jim Adney
jadney@vwtype3.org jadney@vwtype3.org
Laura Kepner-Adney
Madison, Wisconsin
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