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Re: Street Tire Handicap (a bit long)

To: autox@autox.team.net
Subject: Re: Street Tire Handicap (a bit long)
From: GSMnow@aol.com
Date: Wed, 12 May 1999 02:55:53 EDT
Date: Tue, 11 May 1999 12:43:24 EDT
From: RacerRay52@aol.com

In a message dated 5/11/99 12:35:23 PM Eastern Daylight Time, 
jemitchell@compuserve.com writes:

<< What you apparently want is an
 index that perfectly compensates for car/tire performance
 differences and guarantees that the "best" driver wins, which is
 not possible. What if you get what you're asking for and then
 still don't win?  >>

<<<<     Not a perfect index. Perfection is not attainable. Just a better
one. A consistent, stable, rational one.
     I never said that I have been losing a lot. Modesty prevents me
from writing too much about my performance and results.
It is the constant changing and lack of local pertinence
of the PAX that I don't like for local use.
     I'm just seeking a competitive situation that makes
sense to me and is worthwhile to bother with.
     If the PAX were going in the other direction in relation
to HS I still wouldn't like it. >>>>

As has been pointed out, the index has to be adjusted every year to keep up 
with car moves and new cars, as well as drivers figuring out what some cars 
are really capable of. PAX is set by results from large events like nationals 
and tours. These events are usually more open and flowing compared to smaller 
local events. Due to these reasons, we have selected the RTP index created by 
our local 100% national runner Rick Ruth. He takes all the same data as PAX 
but also figures in data from our two local series as well as Cendiv and WAI 
events. The adjustments move our local top driver closer together compared to 
the PAX numbers so it is working for our local events. It is not perfect, and 
never will be, and it is adjusted every year. For this year, HStock got a 
faster index than EStock. This was reflected at Nationals as well as here 
where we have some serious HS drivers and EStock is lightly perscribed, but 
due to the light index, we now have a few new EStock drivers. And EStock just 
won overall index at our last event.

Where I am going with this???

Oh yeah, We use an index (RTP in our case) for both our street tire program, 
and our overall drivers points championship. We award the top 20 each year 
based on the index chosen for that year. The members vote on either the PAX 
or the revised RTP each year before the first event. We have chosen RTP for 
the last several years because it runs us closer on our smaller sites. We 
have no correction for street tire vs race tire for the overall, so drivers 
are encouraged to move to race ruber for overall points, but since our street 
tire can exceed 30 cars it is a good fight all by itself. The faster the car, 
the more it seems hurt by street tires, so the H-stocker has an advantage 
going in against the SS car. This is reduced to some degree by th SS car 
coming with better tires than the HStock cars, but we also had drivers in 
lower classes bringing an extra set of rims with dedicated race street 
compound tires. There is always someone willing to spend to win. I ran my 
Talon on street tires a few times when my beast was not running and it was 
quite fun to see how I do against the other street tire cars. Last year I won 
ST in my Talon, this year I would have been 3rd behind a car in the same 
class, so the index was not an issue, there were 30 other cars behind me. 
Many of them were in vastly different classes. 

On our overall, the top spots are always taken by race tire cars. Top ST car 
was a C-Mod driver in a stock Porsche. He is also a McKamey school instructor 
and drove very well to come in 40th ahead of many race tired cars, there were 
nearly 140 drivers there. Between the best SS and him the difference was 
4.5%, 57.358 for a Corvette vs 60.054 for the Porsche. We also ran a test 
event last year is a bone stock 90 Civic Si on Coper Cobras vs used TA R1's, 
the times were 71 something vs 65 or so. That is almost 8.5% but the Coopers 
are far from great tires for autocross. The differance could have been more 
because the car has manual steerng and the asymetric R1's created VERY heavy 
steering on a tough concrete course in Peru. 

Sorry for running on so long, but in conclusion, all you can really do in the 
ST class is try to improve your position from event to event. this shows you 
if you are doing beter then the other drivers in the class, and that is how 
we score it for the year. If you want to compare to race tire drivers, go 
ahead the points will show your relative performance. If you get a closer 
point value, you came closer to your target. Or like a pair of our local 
drivers did this past wekend, they decided to drive the same car that neither 
had driven before, they rented a Nissan Sentra at the airport for the day, 
and both ran the same car. They had a lot of fun, and fineshed very close. 

Comparing against know good drivers is always a good way to see how you are 
doing, and even figuring percentage of raw times is a great comparison. 
Indexing is an interesting excersize, but will never be perfect. We have 
pretty much accepted the faults of indexing, and the diversity of cars making 
the top positions each event shows it is close for us. In the top 20 we had 
only a 1.7 second spread of index time, but cars from 9 different classes and 
raw times ranging from 57.358 to 62.327 or nearly 5 seconds. The top four 
were ES DS SS HS in just a .5 second spread on index.

Gary M.

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