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Re: Autobahn thrill-ride!
> From quattro-owner@swiss.ans.net Thu Sep 8 15:20:19 1994
> From: "Arun Rao" <rao%frisbee@frisbee.pixar.com>
> Truth is, I'd never had any car to redline before this Bavarian
> projectile that I drove. How "strict" is this redline thing anyway?
> Does all hell break loose if you go over?
>
At least with German and Italian cars it's not very strict. In most
new cars the rev-limiter takes care of protecting the engine from
damage, and that may cut in at anywhere between 200 and 1000 rpm over
redline. In my 100CS it doesn't cut in until almost 7000 rpm, and it's
easy to hit because the engine is completely smooth and quiet up to
that point. Contrast that with the two Lexus GS300s that I drove,
where I could not bear to even let the auto trans take them to the
redline because of the cacophony of noise and vibration.
My old college roommate has a 1971 Alfa Romeo V-8 which was not sold in
this country. He took me on a ride through some back roads around
Springfield MA, and while doing so routinely wound the engine out to
9-10,000 rpm, and it sounded quite happy (really an intoxicating
sound). It looked to me like the redline was at 7 grand, so that's
quite a bit over!
Contrary to what most people think, according to engineers at Adam Opel
AG in Germany, running an engine at the redline is less stressful than
idling it. During idle, oil distribution is less than optimal, and
that's why most engine designers dread the stop-and-go phase of testing
a new engine, as that's where the problems start. Furthermore, at low
intake valve air velocities, the valves are more likely to get dirty
than whilst under load.
For that reason, I may wind the piss out of it, but I never let my
engine idle for more than absolutely necessary, and have repeatedly
been told by mechanics at the dealer that my car seems to have
significantly more torque than usual for that car. I also haven't had
those lifter problems or any other maladies that others have
experienced with the V6, so I guess the engineers have a point.
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John Greenstreet, Senior Engineer (jgreenst@motown.ge.com)
Martin Marietta Government Electronic Systems Moorestown NJ 08057
WPI Class of '75, Temple Class of '94
My new car history:
1972 1975 1978 1982 1986 1989 1992
VW -> VW -> Audi -> Audi -> Mercedes -> Mercedes -> Audi
SBug Scirocco Fox GTI 4000S 190E 2.3 190E 2.6 100CS
POSSLQ's* new car history:
1978 1981 1985 1988 1990 1993
Triumph -> Toyota -> Toyota -> VW -> Audi -> Audi
Spitfire Tercel Corolla Jetta GL 80 90S
*POSSLQ = Person of Opposite Sex Sharing Living Quarters
Note: All Audis and Mercedes above were sold to friends or family.
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