John Carriere wrote:
>I do not agree with putting the F2000 in CM. This is not like putting the
>S2000 in CM. With the S2000, the combination of physical size (especially
>the width of the bodywork at the front and rear extremes) and increased
>weight pretty much compensate for the increase in torque/horsepower and
>slightly wider front wheels. I think the size difference is the biggest
>penalty for the S2. As the F1600 and F2000 share the same physical
>envelope, the weight penalty does not even out the torque and tire size
>differences.
>
>
Most FF2000 chassis are longer than most FF1600, as I recall. For
example, my SE3 is longer than a DB1, although I don't know by how much
>One way to find out is to invite them out to play at regional events and
>see if this is true over time. We have many data points on the S2 vs F1600.
>
>
It won't be a good test until someone like Tommy or Mark devlops one to
near-optimal autox configuration.
>Another way is for SCCA to sanction a test where a Nationals prepped F1600
>can be converted and run under controlled circumstances.
>
As for retro-fitting 1600s, you could require a logobook showing the car
began life as a 2-litre. GCR requires re-homologation for chassis
converted to FF2000. How many of you would go to that trouble?
Nobody's ever shown S2000s to be a factor by devloping one for auto-x.
I think about the time they were classified in CM the British started
buying up all the cars and shipping them across the pond. S2s are hard
to find today.
Spec a hard-compound tire. In addition, mandate a zero wing angle and
possibly adjust weight beyond that. I think the cars have to remain
GCR-compliant, which means wings are mandatory. At autocross speeds the
wings are not effective unless you crank up the angle of attack way
past the norm , or build a special wing with a lot more lift at low
speeds. Control lift by restricting the thickness and chord to what
road-racers are using, specify single -element wings in front, no
wickerbill, along with the zero-angle requirement. Leave the wings,
just make them ineffective at Solo II speeds.
Looking at my rear wing assembly, it has a lower wing with
integrated mount so it cannot be removed. The upper has a fixed front
element, then an adjustable rear element with a wickerbill. Other than
lowering the rear element to level, there isn't much way to render it
ineffective. But at that lowest setting, I wonder how much downforce it
would make at 70 mph? Little or none, I would think. Could it be that
the rear wing, at zero angle, produces a little downforce at 70 mph
which is offset by the weight of the assembly, and the location of that
weight?
Anyone have a wind tunnel? :)
If the cars can be made fairly competitive without major departure
(wing removal, lots of weight) from the GCR specs it could work and also
be good for the class. If I can swap to the autox wheels& tires, reset
the wings to zero, possibly change the nose wings and maybe remove one
of the rear elements, add a weight and I'd probably do some Solos in
it. That's a one-evening, reversible conversion. I realize I'd have to
change spring rates and shock settings to optimize, but that may be
do-able with a 2nd set to be changed out.
Too many variables, without a test.
Rex Burkheimer
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