| Cayman and Boxster Competition Auto Cross, Club Racing, DE, this is the place to discuss the 987 on the track |
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05-08-2009, 09:06 PM
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SCCA stock class autocross rule question
Are the optional Cayman S wheels legal on a Cayman for A Stock?
With an LSD I think it could run with the honduh S2000's.
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LSD - Limited Slip Differential
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A limited slip differential (LSD) is a modified or derived type of differential gear arrangement that allows for some difference in rotational velocity of the output shafts, but does not allow the difference in speed to increase beyond a preset amount. In an automobile, such limited slip differentials are sometimes used in place of a standard differential, where they convey certain dynamic advantages, at the expense of greater complexity.
The main advantage of a limited slip differential is found by considering the case of a standard (or "open") differential where one wheel has no contact with the ground at all. In such a case, the contacting wheel will remain stationary, and the non-contacting wheel will rotate freely– the torque transmitted will be equal at both wheels, but will not exceed the threshold of torque needed to move the vehicle, thus the vehicle will remain stationary. In everyday use on typical roads, such a situation is very unlikely, and so a normal differential suffices. For more demanding use however, such as driving off-road, or for high performance vehicles, such a state of affairs is undesirable, and the LSD can be employed to deal with it. By limiting the velocity difference between a pair of driven wheels, useful torque can be transmitted as long as there is some friction available on at least one of the wheels.
To see the installation of a LSD style unit Click Here -> Article Forthcoming Stay Tuned |
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05-08-2009, 10:15 PM
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Porsche Purist
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Re: SCCA stock class autocross rule question
Yes they are.
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05-08-2009, 10:54 PM
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Re: SCCA stock class autocross rule question
Thanks, I thought so.
I know Street Prepared, Street Mod, and Prepared much better than Stock.
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05-11-2009, 05:58 AM
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Kestrel Racing
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Wheels? Yes. LSD? Nope...
Because the Cayman S wheels were an available option for a dealer purchased Cayman, they should be OK in stock classes. Unfortunately, that LSD would not be legal in stock classes...
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LSD - Limited Slip Differential
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A limited slip differential (LSD) is a modified or derived type of differential gear arrangement that allows for some difference in rotational velocity of the output shafts, but does not allow the difference in speed to increase beyond a preset amount. In an automobile, such limited slip differentials are sometimes used in place of a standard differential, where they convey certain dynamic advantages, at the expense of greater complexity.
The main advantage of a limited slip differential is found by considering the case of a standard (or "open") differential where one wheel has no contact with the ground at all. In such a case, the contacting wheel will remain stationary, and the non-contacting wheel will rotate freely– the torque transmitted will be equal at both wheels, but will not exceed the threshold of torque needed to move the vehicle, thus the vehicle will remain stationary. In everyday use on typical roads, such a situation is very unlikely, and so a normal differential suffices. For more demanding use however, such as driving off-road, or for high performance vehicles, such a state of affairs is undesirable, and the LSD can be employed to deal with it. By limiting the velocity difference between a pair of driven wheels, useful torque can be transmitted as long as there is some friction available on at least one of the wheels.
To see the installation of a LSD style unit Click Here -> Article Forthcoming Stay Tuned |
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05-11-2009, 06:54 AM
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Don't tell them you have an LSD.
What, are they going to crack open the transaxle and check? Cheating is part of racing!  (Especially when dealing with pompous volunteer organizations using a deeply esoteric and completely arbitrary classification system)
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05-11-2009, 08:37 AM
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Re: Wheels? Yes. LSD? Nope...
Originally Posted by Kestrel
Unfortunately, that LSD would not be legal in stock classes...
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Sure it is.
Can be ordered from the factory, it's legal.
Not an aftermarker LSD, just the factory stock one, and only on a 2009 and later.
If the wheels were a dealer installed option they wouldn't be legal for stock.
Since they can be ordered from the factory they're legal. Right Jim?
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LSD - Limited Slip Differential
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A limited slip differential (LSD) is a modified or derived type of differential gear arrangement that allows for some difference in rotational velocity of the output shafts, but does not allow the difference in speed to increase beyond a preset amount. In an automobile, such limited slip differentials are sometimes used in place of a standard differential, where they convey certain dynamic advantages, at the expense of greater complexity.
The main advantage of a limited slip differential is found by considering the case of a standard (or "open") differential where one wheel has no contact with the ground at all. In such a case, the contacting wheel will remain stationary, and the non-contacting wheel will rotate freely– the torque transmitted will be equal at both wheels, but will not exceed the threshold of torque needed to move the vehicle, thus the vehicle will remain stationary. In everyday use on typical roads, such a situation is very unlikely, and so a normal differential suffices. For more demanding use however, such as driving off-road, or for high performance vehicles, such a state of affairs is undesirable, and the LSD can be employed to deal with it. By limiting the velocity difference between a pair of driven wheels, useful torque can be transmitted as long as there is some friction available on at least one of the wheels.
To see the installation of a LSD style unit Click Here -> Article Forthcoming Stay Tuned |
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05-11-2009, 09:07 AM
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Re: Don't tell them you have an LSD.
Originally Posted by AlexMcNabb
What, are they going to crack open the transaxle and check? Cheating is part of racing!  (Especially when dealing with pompous volunteer organizations using a deeply esoteric and completely arbitrary classification system)
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I really hope you are joking.
I am not much for stealing from my friends.
Cheers,
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05-11-2009, 10:46 AM
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Now hold on a second.
Are 2006-2008 Cayman S cars in the same class as a Cayman S 2009 and up? If they are, does anyone consider this fair?
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05-11-2009, 12:34 PM
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Re: SCCA stock class autocross rule question
SCCA classing can't be 'fair', as you would end up with only single model spec classes. I agree that there are varying levels of screwed, and putting the CS with the Z06, elise, and GT3 in SS is preposterous. I also agree that the reasoning for this isn't based on competitive reasons alone, but socio-economic considerations too; if the top car in a class is too expensive for the bulk of the competitors they will not want to pay SCCA dues rather than come in 2nd, so screw those who can buy that car by upclassing it into oblivion. That is really maddening. On top of all that, they do a pathetic job of really proving that a given car would dominate its class. A hunch is good enough for them. So if our only problem was running against an 09 CS we'd be doing OK.
The 06-08 CS, which has only 295hp, .9 neg camber, and no LSD should clearly be in AS. But since they won't give us that, we can at least be happy with BSP rather than ASP. And since LCA's are allowed in BSP now, that is pretty good. You can make your car extremely fun to AX AND be in (what I think will be) a competitive class. That's better than pushing around every hairpin in stock class anyway.
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LSD - Limited Slip Differential
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A limited slip differential (LSD) is a modified or derived type of differential gear arrangement that allows for some difference in rotational velocity of the output shafts, but does not allow the difference in speed to increase beyond a preset amount. In an automobile, such limited slip differentials are sometimes used in place of a standard differential, where they convey certain dynamic advantages, at the expense of greater complexity.
The main advantage of a limited slip differential is found by considering the case of a standard (or "open") differential where one wheel has no contact with the ground at all. In such a case, the contacting wheel will remain stationary, and the non-contacting wheel will rotate freely– the torque transmitted will be equal at both wheels, but will not exceed the threshold of torque needed to move the vehicle, thus the vehicle will remain stationary. In everyday use on typical roads, such a situation is very unlikely, and so a normal differential suffices. For more demanding use however, such as driving off-road, or for high performance vehicles, such a state of affairs is undesirable, and the LSD can be employed to deal with it. By limiting the velocity difference between a pair of driven wheels, useful torque can be transmitted as long as there is some friction available on at least one of the wheels.
To see the installation of a LSD style unit Click Here -> Article Forthcoming Stay Tuned |
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__________________
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Last edited by wpmjr; 05-11-2009 at 12:43 PM.
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05-11-2009, 01:08 PM
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Re: Now hold on a second.
Walter asked about the legality of optional wheels; not lsd.
Currently the new versions are in the same classes as the previous versions. That seems appropriate and fair enough to me, at least for this year. We'll see if the new CS is significantly quicker than the original version, and if it can compete against the Z06s, Lotuses, and GT3s in SS.
Annual classification and reclassification has to be one of the most thankless jobs in all of SCCA. Every version of every car has to be someplace in the SS through HS stock classes, so only a few get to be one of the hot set-ups for each class. The upper (SS) and lower (HS) ends seem particularly problematic. There are 4 pages of cars listed in HS, but Mini Coopers have won nationals 5 out of the last 6 years. Maybe that seems unfair to all the other HS car owners, but having a separate class for every car doesn't seem to be a very viable solution either.
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LSD - Limited Slip Differential
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A limited slip differential (LSD) is a modified or derived type of differential gear arrangement that allows for some difference in rotational velocity of the output shafts, but does not allow the difference in speed to increase beyond a preset amount. In an automobile, such limited slip differentials are sometimes used in place of a standard differential, where they convey certain dynamic advantages, at the expense of greater complexity.
The main advantage of a limited slip differential is found by considering the case of a standard (or "open") differential where one wheel has no contact with the ground at all. In such a case, the contacting wheel will remain stationary, and the non-contacting wheel will rotate freely– the torque transmitted will be equal at both wheels, but will not exceed the threshold of torque needed to move the vehicle, thus the vehicle will remain stationary. In everyday use on typical roads, such a situation is very unlikely, and so a normal differential suffices. For more demanding use however, such as driving off-road, or for high performance vehicles, such a state of affairs is undesirable, and the LSD can be employed to deal with it. By limiting the velocity difference between a pair of driven wheels, useful torque can be transmitted as long as there is some friction available on at least one of the wheels.
To see the installation of a LSD style unit Click Here -> Article Forthcoming Stay Tuned |
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05-11-2009, 03:02 PM
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Kestrel Racing
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Oops...
Originally Posted by Walter
Sure it is.
Can be ordered from the factory, it's legal.
Not an aftermarker LSD, just the factory stock one, and only on a 2009 and later.
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Oops! Yup... you're right. On the 2009 with PDK an LSD would be legal. I was thinking you were retrofiting an older model... my mistake.
I'd like to see how a 2009 "base" Cayman would do against the S2000 in AS as well. I agree that it could be close!
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05-11-2009, 04:23 PM
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Re: Now hold on a second.
Originally Posted by Jim Michaels
Annual classification and reclassification has to be one of the most thankless jobs in all of SCCA.
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The award for Understatement of the Year goes to Jim Michaels!
Clearly, one would have to have a seriously masochistic bent to join the SCCA's SCAC (Stock Class Advisory Committee). My hat is off to anyone that would sign up for that kind of abuse.
I will have to say though that since getting a Porsche, I really have enjoyed autocrossing with PCA more than in my SCCA days because, as a single marque club, the classifications are inherently more fair. And with Showroom Stock classes, one can focus on being a better driver rather than an engineer (no offense to any engineers reading this!).
I also found that the preparation allowances in SCCA Stock Class somewhat peculiar (stock class cars can change the front but not the rear sway bar????). PCA's Production class seemed to me to be a much more logical set of preparation allowances if you wanted to step beyond Showroom Stock.
It will be interesting to see what, if anything, PCA does for 2010 regarding classing the new Crocs. From my perspective on the autocross course, the single biggest draw back to the 1st generation cars is the lack of a LSD. I would wager that the extra HP and Torque is a negligible difference, but having an LSD and being able to apply power in slaloms and on corner exit should be significant advantage.
In my early AX days, I had a 2nd generation RX-7 with a LSD. I had an opportunity to run at a SCCA National Tour in a very similar car to my own, minus the LSD. I remember thing, "WTF is going on with all this wheel spin?". I have to say that I have been revisiting those days with my Cayman.
Brian
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LSD - Limited Slip Differential
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A limited slip differential (LSD) is a modified or derived type of differential gear arrangement that allows for some difference in rotational velocity of the output shafts, but does not allow the difference in speed to increase beyond a preset amount. In an automobile, such limited slip differentials are sometimes used in place of a standard differential, where they convey certain dynamic advantages, at the expense of greater complexity.
The main advantage of a limited slip differential is found by considering the case of a standard (or "open") differential where one wheel has no contact with the ground at all. In such a case, the contacting wheel will remain stationary, and the non-contacting wheel will rotate freely– the torque transmitted will be equal at both wheels, but will not exceed the threshold of torque needed to move the vehicle, thus the vehicle will remain stationary. In everyday use on typical roads, such a situation is very unlikely, and so a normal differential suffices. For more demanding use however, such as driving off-road, or for high performance vehicles, such a state of affairs is undesirable, and the LSD can be employed to deal with it. By limiting the velocity difference between a pair of driven wheels, useful torque can be transmitted as long as there is some friction available on at least one of the wheels.
To see the installation of a LSD style unit Click Here -> Article Forthcoming Stay Tuned |
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05-11-2009, 04:33 PM
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Re: Oops...
My understanding is that anyway one can configure a new Cayman using the standard list of options would be legal for stock class. As discussed in an earlier thread, this does not mean that any configuration one could get PAG to build through "special wishes" would be legal. In case of on-site protest, SCCA advises each competitor to be able to supply any paperwork supporting the stock status of the car.
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05-11-2009, 05:12 PM
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Re: Oops...
Walter: Sorry I missed your question to me in post #6.
Actually, the wheels don't even have to be Porsche wheels to be legal in stock classes. They do have to be the "same size" as one of the optional sets of wheels. By same size they mean same diameter, width, and "as installed (including wheel spacers, if applicable) it does not have an offset more than +/- .25 inch from a standard wheel for the car." Thus, light-weight forged wheels in the same dimensions as one of the sets of optional factory wheels would be legal.
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Wheel Enhancement
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Nobody gives you more ways to get the look you want:
1. Purchase new Porsche Factory alloys.
2. Purchase like-new used or restored Porsche alloys from us.
3. Have us refinish your Factory alloys. We restore, anodize, polish and chrome plate.
4. Purchase our aftermarket wheels--we offer the very best, including Kinesis, Fikse, BBS, HRE and Champion to name a few.
5. Exchange your straight, true Factory alloys for Factory alloys pre-finished the way you want.
6. Exchange your scratched/curb damaged Factory alloys for new or refinished Factory Alloys.
7. Trade in your straight, true Factory alloys for aftermarket or Factory wheels.
http://www.wheelenhancement.com |
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05-11-2009, 11:11 PM
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Looks like Pandora's box is opened.
Personally, I prefer NASA classing to SCCA by a pretty significant margin. SCCA classifications have always struck me as being severely preferential to the fan favorite cars (CSP Miata dominance, anyone?), while not really being objectively fair. I'll be honest, I don't feel at all obligated to carefully list every little tweak done to my car to groups using the SCCA rule system. Particularly not when NASA groups are so much more lenient with allowing drivers to FIX problems with their cars without being stuck in some insanely competitive class. I really don't wanna have to flip through dense, archaic, and overly complex classifications just to be a parking lot bandit on a cone racing course. (Now if I was spec racing at VIR, it would be different story) But for Autocross? Gimme a break, let people do basic mods like camber plates without upclassing them into oblivion. I much prefer to give my money to NASA groups where the driver and getting out there and actually racing is more important than how competitive a car "should be".
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05-12-2009, 07:05 AM
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Kestrel Racing
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SCCA isn't evil
Originally Posted by BGLeduc
Clearly, one would have to have a seriously masochistic bent to join the SCCA's SCAC (Stock Class Advisory Committee). My hat is off to anyone that would sign up for that kind of abuse.
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+1. I think the SCCA and the folks on that SCAC do a great job, and I've enjoyed running with them over the years. I have nothing but praise for the work they do, and I continue to participate in local Solo events whenever I can. There is no way to class every car perfectly, but I feel they do as good a job as they can given all the variables out there.
Originally Posted by BGLeduc
I will have to say though that since getting a Porsche, I really have enjoyed autocrossing with PCA more than in my SCCA days because, as a single marque club, the classifications are inherently more fair. And with Showroom Stock classes, one can focus on being a better driver rather than an engineer (no offense to any engineers reading this!).
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+1 again. Nothing at all against SCCA, but I'm having more fun running with the PCA folks these days. Maybe it's just the single marque camaraderie. Maybe the classing is a little more fair (although I'm running against a fully track prepared older 911 SC in my bone stock Cayman!). Whatever the reason, I find myself going to PCA events over SCCA events if there is a conflict.
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05-12-2009, 07:44 AM
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Re: Looks like Pandora's box is opened.
Originally Posted by AlexMcNabb
Personally, I prefer NASA classing to SCCA by a pretty significant margin. SCCA classifications have always struck me as being severely preferential to the fan favorite cars (CSP Miata dominance, anyone?), while not really being objectively fair. I'll be honest, I don't feel at all obligated to carefully list every little tweak done to my car to groups using the SCCA rule system. Particularly not when NASA groups are so much more lenient with allowing drivers to FIX problems with their cars without being stuck in some insanely competitive class. I really don't wanna have to flip through dense, archaic, and overly complex classifications just to be a parking lot bandit on a cone racing course. (Now if I was spec racing at VIR, it would be different story) But for Autocross? Gimme a break, let people do basic mods like camber plates without upclassing them into oblivion. I much prefer to give my money to NASA groups where the driver and getting out there and actually racing is more important than how competitive a car "should be".
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I agree that SCCA isn't perfect, but I think you should reconsider hiding your mods. I know it's tempting and you might be able to rationalize it like you have in this thread, but at a local event, even if you disclose a disallowed mod to your fellow competitors, they'll probably not protest it- most want more people in their class and aren't that worked up about it. At regionals and nationals forget it.
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05-12-2009, 08:59 AM
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+1.
At the local level, there certainly isn't enough cars per class. And there is more leeway. (No reason for Street Mod to be the biggest class)
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05-12-2009, 09:46 AM
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Re: Looks like Pandora's box is opened.
Originally Posted by AlexMcNabb
Personally, I prefer NASA classing to SCCA by a pretty significant margin. SCCA classifications have always struck me as being severely preferential to the fan favorite cars (CSP Miata dominance, anyone?), while not really being objectively fair. I'll be honest, I don't feel at all obligated to carefully list every little tweak done to my car to groups using the SCCA rule system. Particularly not when NASA groups are so much more lenient with allowing drivers to FIX problems with their cars without being stuck in some insanely competitive class. I really don't wanna have to flip through dense, archaic, and overly complex classifications just to be a parking lot bandit on a cone racing course. (Now if I was spec racing at VIR, it would be different story) But for Autocross? Gimme a break, let people do basic mods like camber plates without upclassing them into oblivion. I much prefer to give my money to NASA groups where the driver and getting out there and actually racing is more important than how competitive a car "should be".
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I can't believe that you publicly disclose here that you cheat, that you use such lame rationalizations (let's just go out and race...") to justify it, and you seem proud of it, to boot. Perhaps in your opinion, the rules are long and arcane, but they are the rules that people play by, and there's no difference between cheating while autocrossing in a parking lot or on the track at VIR. Your fellow competitors in each venue have to trust that you are following the rules just like they are. Obviously if you're cheating, then your times and class position are complete BS. If you count the people you run with as your friends, then you are cheating and lying to your friends, too. I guess if you can live with that, so be it. If you don't like the rules, then you should either not run with that group, run in the next class up, which might mean you actually have to improve as a driver to do well rather than cheat, or go through the process to get them changed.
Sheeeeeeeeesh.
brad
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Last edited by beez; 05-12-2009 at 10:19 AM.
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05-12-2009, 10:08 AM
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PCA / POC Member & Club Donor
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Re: SCCA stock class autocross rule question
+1 Beez
Below is a copy of an email I sent to a number of friends recently after experiencing some very disappointing behavior among fellow racers. It is certainly a bit of righteous preaching, but hey it’s me.
I suggest you turn up the volume and watch the entire clip, all of it, then send it off to a few other folks.
Cheers,
----
Gentlemen (yes, I mean it),
Watch this clip: YouTube - Bobby Jones - Calls 1 stroke penalty on himself
This is how we should all play the game, any game, and teach our children to do the same. While my greater passion is racing, the greatest game ever invented is golf, where honor is revered above winning. Where else do you play a professional game with no referees, are expected to call a penalty on yourself, will always help your opponent find his lost ball, and when man wins a hole he is given the “honor” of hitting first on the next tee.
How do we apply these lessons and put the gentlemen back in “gentlemen racing”. Some of the behavior I witnessed in the last week or so makes me wonder if we can.
Cheers,
XXX – XXX.XXX.XXXX
Ps – yes, I am tired, and I promise not to make these sermons too much of a habit
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