Date: Fri, 22 Oct 1999 20:08:45 EDT
Reply-To: Vantaztik@AOL.COM
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Roger&Zoe Ann Banker <Vantaztik@AOL.COM>
Subject: The much maligned 1.9 head on 2.1 engine
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Thank you to the few who have sent positive and sensible responses. But my
oh my, so many negative responses. I guess some of us that grew up as free
thinkers with the old split-windows have now become the Pat Buchanan
generation, condemning anything different out of hand without regard for the
facts. So I'll address a few of your concerns, then I will wait and report
on how the engine is doing every 50,000 miles.
1. 1.9 heads are identical to 2.1 heads, the only difference is the squench
area, which gives the higher compression. The 2.1 engine has the same
diameter pistons, just a longer stroke, so the top end is the same. If you
do something crazy like raising the compression ratio to 14:1, it will put
much more stress on all the parts. But we are only talking a slight increase
here, still within the specs of the Bentley manual, maybe 9:1. So the engine
is already designed to take this compression. Many family cars have higher
compression, we aren't talking anything radical here.
2. Head longevity: My heads should last just as long as anybody's. What
kills the Vanagon heads is corrosion and overheating. I have the lower
thermostat on the radiator fan, and the cooling system has capacity to spare
to keep temperatures within normal ranges. I am using non-phosphate
antifreeze to prevent corrosion. And don't we rebuild when compression is
too low? Perhaps mine will last longer since it is starting with higher
compression.
3. Stress on the lower end: Slightly higher compression has no effect on
the low end of the engine. The greatest stress on the rods, crank and
bearings is on the exhaust stroke. The crank is pushing up against little
resistance, then it must reverse all that rod and piston momentum and yank
them back down. This reversal of pushing and pulling is the greatest strain.
On the power stroke there is constant pressure pushing down on the piston,
which the system is better able to deal with.
4. After market exhausts: All after market systems are not loud and
inefficient. While some back pressure is needed to make the engine run
properly, too much reduces power. The Fast German Auto system has a lower
pitched exhaust note, and less restriction. It still runs all the pipes thru
one catalytic converter and muffler, and it still maintains proper pipe
length and some back pressure. The lower back pressure should match up well
to the higher compression. I don't know if their pipes are thin, but I will
be painting them with high temp paint with ceramic before they are installed
to help longevity.
5. Proper oil: After break-in, Castrol 5/50 is the best there is. If you
use any oil with a top rating of 30, you are risking thinning and break down
of lubrication in hard use, or if the engine overheats. I will also use
Slick50.
6. For the person who suggested I can't tell how powerful a Vanagon should
feel, I have been driving VW busses and vans for almost 30 years. I know
when one goes faster than new, and the one I drove had extra power.
I own a 1987 Syncro Adventurewagen. Loaded to camp with passengers, it
weighs 5000 lbs. The stock engine just isn't adequate. These minor mods to
help the entire rpm range will hopefully make driving much nicer, I'm even
considering adding cruise control!
Please don't bother flaming me, I won't respond until the 50,000 mile report.
Roger and Zoe Ann Banker
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