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Subject:Re: 1981 Questions
From:John Brush
Date:Thu, 14 Feb 2002 21:37:34 -0700

>1.      Your  compression is quite low. it is very likely that your van
>won't start once the weather warms up and you have driven a few miles.
>Normal is around 120-130 psi, VW allowed some broad tolerance between
>cylinders (20psi?) and low is around 100 psi.

You folks know much more than I ever will, but I just want to ask if you
are certain of this number for low compression, as I think I have seen it
somewhere that 85 to 90 is the bottom end of the VW spec. Where can I go
to double check this?

The reason I ask is that my 81 reads mid 90's on all 4 holes, and I never
had any problems starting it in major heat. In fact, the thing runs so
darn well that every time I am about to tear it down and rebuild it, I
change my mind because there is just nothing wrong with it. That
frustrates me sometimes. :-) I would like the little boost in output that
a rebuild would give, but its like a surgeon cutting into a healthy body.
I just can't do it.

Please help me understand why the low compression might cause a problem in
hot weather?

Is it "legal" to just hone the cylinders and put in oversize rings? On
V8's I would do that a lot, but somehow I got the idea that wouldn't be
cool on a Type IV. OTOH, the only thing I know about these babies is what
all of you folks here have taught me.

Best Regards from Utah,

John