Well, I've been informed of quite a few important details on this subject.
First of all, it makes complete sense (now that someone mentioned it) that with
the long laps of LeMans, the idea of leaning out the mixture to gain an entire
extra lap of fuel mileage is rather extreme. I found this very interesting in
terms of strategy.
Again, I KNOW why the flames from the exhaust happen. No need to tell me
thrice times twice. I guess I should have been more specific? Though it is
too late now to revise my comment without losing face, I suppose it should have
said,
"Flames from the exhaust on a NA engine, in a sprint race, on a short course,
is not a good thing... in general, but does suggest that the engine is
comfortably happy, since being comfortably rich is a happy place to be."
For instance, you don't often see flames from the exhaust on a F1 car, do you?
Turbocharged engines are another can-o-worms.
-STEFAN ...used to lurk, because of the general "bicker" mode of team.net,
might go back
In a message dated Tue, 19 Jun 2001 9:57:18 AM Eastern Daylight Time, Tom
Tweed <ttweed@san.rr.com> writes:
<< First Stefanv@aol.com wrote:
>Flames shooting out of the back of a car (especially running
>in endurance racing) is not a good thing!
[snipped]
The Audi is turbo-charged. My understanding is that there is no way to
cut the rich mixture that is flowing to the motor under boost just BEFORE
the driver comes off the gas, which would be the only way to stop the
flames out the pipe. No engine management programming can anticipate
when the driver is going to lift. When he comes off the throttle, there is
excess fuel charge in the induction system that has to go somewhere, and it
goes out the exhaust pipe, where it is ignited by high temps there.
If they were set up with a leaner mixture, the turbo engines would not
make the power they do and probably burn up the pistons in no time.
>Poorer fuel mileage means more pit stops.
>More pit stops means you lose the race.
They didn't seem to have any problem with fuel consumption hurting their
results.
Then WheelerDealerUSA@netscape.net (Jonathan Kniskern) wrote in the same
thread:
>See what a *whole lot* of manufacturer support can do for a team?
>Supposedly the rear-end swap took them 7 minutes last year!
As I remember, the swap took only 4-1/2 minutes last year,
but they say the memory is the first to go....
>Kudos to Bentley for sure! A friend told me that there chassis came
>from Audi - is that true?
No, only the engine block. The rest of the car was a "clean sheet" design,
according to the Bentley project manager who was interviewed on the show.
--------------------
Tom Tweed mailto:tweedt@ucsd.edu
La Jolla, CA or ttweed@san.rr.com
"I started out with nothing and I've still got most of it left."
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