Our club will be voting next month on adopting a new car classing system for next season. I'd love to get opinions from experienced members of some of the larger clubs on here.

Our reasoning for adopting a new car classing system is to open up a 3rd class (more people can walk away with a trophy) and to help level the playing field. One thing to keep in mind is that our car count is now 15-30 per event, which is why we started with only a two-class system. I'm hoping we have enough car to support one of the following options:

Classing Options

1. Street = 300 treadwear and above, Performance = Under 300 treadwear. This is the system our club currently uses - a two class system based on treadwear.

2. FWD, RWD, AWD. Three classes based on drivetrain. Treadwear doesn't matter, you compete with everyone in your class regardless of mods. Can be used with or without PAX.

3. SCCA Divisions w/PAX. I adopted this system from the WSCC and it seems to work great for them, although they have quite a lot more competitors at their events then we do. We break cars down into SCCA/CASC national classes to obtain a PAX index factor then, depending on PAX class, you are grouped into three divisions - Street, Performance, Street Modified.

Street = Only SCCA Street classes: SS, AS, BS, CS, DS, ES, FS, GS, HS - these classes mandate stock cars with street tires only.
Performance = SCCA classes under Street Touring: STU, STR, STX, STS, STC, STF - covers mildly modified cars and mandates street tires only. Plus all SCCA classes that allow r-comp tires - Street Prepared, Street Modified, Prepared, Modified, or Kart - covers medium-highly modified cars on r-comps.
Street Modified = All SCCA classes that allow r-comp tires, similar to above, but competitors instead choose to run street tires: Street Prepared, Street Modified, Prepared, Modified, or Kart - covers medium-highly modified cars that have chosen to run street tires and therefore are subject to the street tire index.

4. Street NA, Super Street, Street Unlimited. These classes are used at MAP Proving Grounds in Brainerd. Again, they have 150 cars competing at their events, substantially more then our small club.

Street NA = Any 4-cylinder naturally aspirated street car. Must have Interior - OEM dash, heater, carpet, 2-front seats, headlights and taillights.
Super Street = Must have Interior - OEM dash, heater, carpet, 2-front seats, headlights and taillights. Must be running STOCK turbo, STOCK cams, STOCK internals, STOCK injectors. Cars NOT eligible: C5 & C6 Corvette, GTR, Viper, 911 GT2/3, Exige, or other exotics.
Street Unlimited = Must have Interior - OEM dash, heater, carpet, 2-front seats, headlights and taillights.

These classes are 140+ treadware. MAP uses a fourth class, Unlimited - which allows any mods and r-comp tires. Our Club does not have enough drivers to support this fourth class so we would have to decide weather to outlaw r-comp tires or allow them in one or all of the three classes. Also, Proving Grounds uses the PAX index to calculate points, so again, we would need to decide weather to adopt that as well or use raw times.

Thank you everyone for your input, it's much appreciated!

@MarcGSR I'm not sure I want to make a recommendation, but I can tell you a bit about our experience.

We used to have 30-40 competitor events when we were using SCCA-like classing. About 8 to 10 years ago, just before my time, the group moved to a completely in-house approach with 5 classes: A, B, C, D, and E.

Our 5 classes are aggregations of SCCA's Street Classes. The precise mapping escapes me right now, but the principle is that lower performance cars, say FS to HS go to E class, then the next group to D, etc. Some SCCA groups might materialized in our baseclasses as E + 7 points, too.

The points are important as we have a simple prep points schedule. You go through it (less than one page), add up your points, and for every 15 points, you move up one class. Obviously, this makes A class unlimited, which has not been a problem in general.

Advantages:

• very beginner/new person friendly vs. SCCA rule book
• no PAX math
• minimal maintenance as the only adjustments from one year to the next is baseclass as SCCA moves cars to new baseclasses
• lets people build cars that are not autocross specific builds be competitive

Disadvantages:

• some (usually the slower drivers in modded cars; or the fast guys in unmodded cars) want PAX, but they get over it

Since 2009, with the exception of some down years due to factors not related to classing, our series has been solid with average participation in the 80 to 90 competitor range.

This year, we considered a move to SCCA and polled our competitors. The majority preferred status quo and even those who wanted SCCA, recognized the challenges posed by SCCA classing for bringing in new participants.

To grossly simplify things, I would say the following: If your focus is on competition, then SCCA is it. If your focus is on community and fun, then not SCCA.

If you want to see our material and get a sense of how your group would work in it, it's all here.

In case it is of interest, here is the rationale we provided to our members for our decision to retain our classing system.

Thanks for sharing Naresh, this is a very interesting classing system and I definitely see the benefits. With that being said, I'm afraid our smaller club, with only 15-30 competitors per event, would be able to support 5 classes.

We typically have 70-ish cars per event (low this years was 65, high was 95) and we run largely SCCA class structure. Most of our competitors also run with the SCCA, so in most cases they already know their class. If they don't, we can figure it out for them, though we are not obsessive with the minor details. It's just something everybody in this vicinity is comfortable with, since there are 3 or 4 very active Regions within a 2 hour drive.

Almost nobody runs the more esoteric classes, and we usually have about 3-5 cars per populated class. It means we give out a lot of trophies, but I don't mind.

I did add a "Classic Street Car" class for mostly-stock cars built in 1978 or before, on street tires, We get a couple participants in that.

Thanks Duke, sounds like you have some pretty large events. They must be a blast! None of the competitors in our club compete in SCCA or CASC-OR events (we are the only club within an 8hr drive). Therein lies our dilemma, we need a classing system that promotes fun and fair competition and that will work with a smaller amount of competitors (15-30 competitors per event).

Our current two-class system based on treadwear worked well when we started Autoslalom five years ago with a small car count but has now evolved into who can/wants to spend money on r-comps takes home the trophy, which is only a couple people. Since we have grown in numbers, I feel we can support a 3rd class and still have a good amount of competitors in each class to keep things fun.

@MarcGSR - About 5 years ago we had about 30 cars per event. At that point we also ran the SCCA classes, but we would gather 3-4 similar classes together to avoid a bunch of 1- or 2-car classes. So we would roll, say, the bottom half of Stock into one class depending on turnout. Since we had no championships that would vary from event to event.

I like the mod-points idea, especially since you could also use that to handicap between the different classes within a given category. You could assign a starting handicap based on where the car would fall in SCCA's Street category. So, for instance, a car that would fall into H Street gets a handicap of zero points, G starts out with 2 points, F starts out with 4, E with 6, etc etc so that by the time you get to an AS or SS car, they are almost all the way to getting bumped into your Performance Class.

That way a slow GS car could have more modifications before getting bumped than would be allowed for a BS car that is pretty quick right out of the bucket, That would go some way toward equalizing the various performance potentials. It also means you'd only have to refer to the Street Class assignment list for the base handicap, which gets updated every year, and you can continue to set your own rules.

Back when I was New York Region SCCA's Solo Chair, I convinced the membership that we should stop handing out attendance trophies (one driver classes) and create some competition. Our ladies and novice classes already ran PAX, so we just made a few more PAX categories:

Stock (now SCCA Street): SS, AS, BS...HS

Touring: ST*

Street Prepared: ASP, BSP...FSP, SM*

Builder: AP...GP, AM...FM, FSAE, CAM, etc.

The categories have been tweaked a few times since I left, but the general idea is that the fastest drivers (by PAX) get both the event trophies and season points in each category...and we don't have to go through the headaches of bumping to fill classes. As an added benefit, we have a small group of drivers who bum rides instead of driving their own cars at our events, and they like this arrangement because they can run in any class within the category and still collect season points.....

@Duke I like the mod-points idea as well. We wouldn't have enough cars to support the classes (there's a lot of street/stock classes) and would have to end up grouping them together. I think 3 classes is the most our car count would be able to support (at least so far).

@vreihen you listed categories very similar to option #3 and what the WSCC uses. The difference being, grouping all Street Touring classes together with all classes that allow r-comps (SP and up). While rcomp classed cars /not/ running rcomps is another class.

The reason being is that obviously PAX calculations are done with Street Touring cars running on street tires while Street Prepared and up cars on r-comps. Grouping these classes together and applying PAX would therefore be 'fair'.

Our club (and WSCC too it seems) has a lot of SP and up cars (PAX factor calculated with rcomps) but running on street tires. The third class would be those cars. You apply the Street Tire Index (.075) x PAX in this class only - everyone in the class is subject to the same modifier, thus keeping that class 'fair' and PAX 'accurate'. I hope this makes sense.

@MarcGSR said:

@Duke I like the mod-points idea as well. We wouldn't have enough cars to support the classes (there's a lot of street/stock classes) and would have to end up grouping them together. I think 3 classes is the most our car count would be able to support (at least so far).

Yeah, I understand that point! My thought was that you would roll all the SCCA Street classes into your Street category just like you planned, but that each car would be assessed a base number of "performance points" assigned by where they would fall if you were using SCCA Street classes. That wouldn't really matter on totally stock cars because they would all still be eligible for your Street class. The base points come into play for modifications, For instance, a fast B Street car has enough base points applied that it only gets 1 modification before having enough points to get bumped into your Performance class. An A Street car maybe can't be modified at all, and a C Street car can have 2 modifications and still stay in street... and so on down the line to a slow H Street car, which can have 5 or 6 modifications before it gets bumped.

All mods are not created equal so you might need to assign different point values to each modification based on effectiveness. You could make <300 UTQG tires a mod and assess that X points. It was just a rough concept of a way to even out the performance potential without resorting to dozens of classes and related PAX indexes.

Ahhhh yes, I think I get it now @duke if I'm understanding properly, you're saying to still have 3 classes - everyone starts off in Street and as mod points are assigned they are bumped into the second and third class. Now, what I would need to take some time to figure out is what points threshold puts you into the second and thrid classes so there is a fairly competitive split between the medium to heavily modified cars...

@MarcGSR - Exactly. And what my "base points" scheme does is handicap it so that the fast stock cars start out closer to the second level than the slow stock cars do. It's just a thought, and if you assess handicap points based where the car falls in the SCCA Street classes, it shouldn't be hard to implement.

Thanks a lot for your input @duke and @MCOAutocross for the reference material. I think it would be pretty easy to set the points threshold bumping from Street to 'Class 2'. Figuring out when cars have been 'modified enough' to bump from 'Class 2' to 'Class 3' may be a little more difficult to decide.

I wish I had this option in my head earlier, I really like it. As we are voting on car classing and scoring for next season at tomorrow night's meeting, I won't have enough time to set out the details, it may be too late for me to throw in another option.

So @MCOAutocross @duke, funny story lol. I brought up the MCO points system at our meeting tonight and it was voted in! We will be running your rules/system for our next season! =D

Now, we are just working on slimming down your 5 classes (A through E) into 3 classes and figuring out where the points split should be to bump you into the next class. Thank you!

@MarcGSR said:

So @MCOAutocross @duke, funny story lol. I brought up the MCO points system at our meeting tonight and it was voted in! We will be running your rules/system for our next season! =D

Now, we are just working on slimming down your 5 classes (A through E) into 3 classes and figuring out where the points split should be to bump you into the next class. Thank you!

We are flattered. I'll pass this one to the guy who came up with it years back. I'm sure he'll be pleased.

If you need any help interpreting something, email autocross@mco.org.

N

@MarcGSR said:

The reason being is that obviously PAX calculations are done with Street Touring cars running on street tires while Street Prepared and up cars on r-comps. Grouping these classes together and applying PAX would therefore be 'fair'.

Unfortunately, there are factors in play (weather and temperature) that make any mixing of street tires and R-comps not as cut-and-dry where this is a fair grouping. I'd bet that street tires would out-perform R-comps in a heavy rain with standing water, and can tell you from many late-season autocrosses with temperatures below 45F (7C) that R-comps can't get enough heat in them from an autox run to even stick on par with street tires. We had a debate over this when devising our own local groupings, and defining the groups so that everyone was on similar tires was a primary goal.....

@vreihen I completely agree with you and ideally Street Touring and Street Prepared classes would always be separate. However, a lot of drivers around here that fall under Street Prepared or Street Modified are running street tires. The PAX numbers from these classes are calculated using fully prepped cars running r-compounds for the majority of the time. For us to have a 'fair' class, we would have to apply Rick Ruth's Street Tire Index (0.975) to the Street Prepared PAX Index factor, for cars not running r-comps. This is why cars, with the Street Tire Index applied, would be grouped together in one class while cars using standard PAX factors - Street Touring and Street Prepared on r-comps - would be together in a separate class.

What does NY Region do with their Street Prepared class in such a situation? Do they use a Street Tire Index to compensate or do they run standard PAX and those not on r-comps just deal with the handicap (which, in reality, is fair for being under-prepared in class)?