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      World of Wheels volunteers needed   02/08/2018

      Go here to sign up on the sheet if you can spare some time to help in the booth. Help is also needed and appreciated for setup and tear down. https://docs.google.com/document/d/1ULmhhNo7nK2dEgrvcdFmSPx0uMUPMl4WxbUcwfXz-Is/edit?usp=sharing
Magner

Car Classing Guide + Help Thread

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NYC is for cars that have not been classed and just want to run without a PAX adjustment on raw time. There is a Rookie of the year trophy however, which is why there is a Rookie list but they must compete in one of the three trophy classes.

 

I must have gotten the back seat removal rule confused between the two classes. I wonder where I got the idea that you could remove interior in SM. must have been from reading the prepped and modified rules lol.

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Thanks for the clarification, guys

 

I'd like to get down to peg city again this summer. I came last summer but didn't time it right with one of your events. At the end of the season, trophies are given to the top 3 drivers in Street, Mixed, Modified, correct? What about overall points, is there a season champion trophy?

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no overall champ trophy. That would just go to Jeff every year anyway -_-

 

also number of trophies per class depends on class size. More than three trophies can be awarded if a large number of racers qualify for the championship (ie compete in enough events, usually one more than half of the season)

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Slight correction. NYC isn't really a Division - there aren't any points or trophies in NYC. It's more of a catch-all so that if you aren't sure which class you belong in, you can go into NYC and just race for fun. It's there for ease of registration in case you don't know where you belong.

 

Also note that there is a slight change to the rookie of the year (ROTY). It used to be just one trophy for one person to win, but now we've expanded it to be a whole Division called Novice Division. Same qualifications apply - you must have run less than half a season (8 events) prior to the start of this year. The advantage of this is that there might be enough entrants to have multiple trophies in Novice Division and there should be a points race all season long instead of just calculating the ROTY at the end of the year.

 

Check the Supp Regs for more detailed info.

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Slight correction. NYC isn't really a Division - there aren't any points or trophies in NYC. It's more of a catch-all so that if you aren't sure which class you belong in, you can go into NYC and just race for fun. It's there for ease of registration in case you don't know where you belong.

 

Check the Supp Regs for more detailed info.

 

I currently don't have the option for selecting NYC on MSR. If you don't want to go through the trouble of classing your car, you can select A Mod as your class.

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Thanks for all your help guys, I have a pretty good understanding of how you run your classes. One thing I'd like confirmation on is your Street Tire Index.

 

Since I fall into the SCCA class of SMF (which allows r-comps) but I am running street tires, I would be placed in the WSCC Street Modified division and my PAX time would be multiplied by 0.985, correct?

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Thanks for all your help guys, I have a pretty good understanding of how you run your classes. One thing I'd like confirmation on is your Street Tire Index.

 

Since I fall into the SCCA class of SMF (which allows r-comps) but I am running street tires, I would be placed in the WSCC Street Modified division and my PAX time would be multiplied by 0.985, correct?

 

You got it.

 

We have created a Modified Street Tire Division that contains all the SP, SM, Prep, and Mod classes, but only using street tires. We've created a separate set of classes that take the "street tire index" into account, all falling within this Division. In this case, instead of registering for SMF (which uses 0.853) you should register for SMF-S (which uses 0.840). This also tells us that you are in the Modified Street Tire Division, so you go up against onther guys in similar classes, also on street tires.

 

If you were to register in the "true" SMF, that means you'd be up against other cars on R-comps in the Mixed Division.

 

Because the 0.985 gets applied to all Modified Street Tire Division classes (all ending in "-S"), there's no real advantage to anyone in this Division. They all get the same modifier. The difference comes into play when comparing across Divisions, e.g. comparing an SMF-S car to a BS car, for example. This only happens for novices, as novices are spread throughout the various classes and we are forced to use pax times to compare them to each other. The only other thing that the 0.985 is useful for is for overall pax times, which is only used for bench racing so it doesn't really matter anyway. :)

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Thanks for the great explanation, Beau.

Where did you find the SMF-S PAX factor 0.840? I looked in the Supplemental Regulations and saw only the standard PAX factors.

How did the WSCC determine 0.985 for a 'street tire index'? There must be a reason for that specific number.

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The pax factor for SMF-S is simply the pax factor for SMF multiplied by the local Street Tire Index. That is, 0.853*0.985 = 0.840.

 

We came up with 0.985 a few years ago based on the St. Andrew's surface. At the time, the SCCA was using a Road Tire Index of 0.975 I think. This was before Stock became Street (Stock Classes still allowed R-comps), but there was a movement toward street tires, and the SCCA tried to find a compensation factor for the difference between street tires and R-compound tires. Most of their data is based on grippier surfaces than what we have, so we adjusted the 0.975 to be 0.985 based on a couple of factors. Mainly, our surface doesn't have as much ultimate grip and therefore there isn't as large of a gap from street tires to R-comps. We considered the opinions of some of our long-standing local members and also looked at results of similar cars and how their run times were affected by different tire compounds. In the end, we settled on 0.985. It may not be perfect, but then again neither is any pax factor.

 

Since we group cars together based on the Divisions, the Street Tire Index is never a determining factor in any of the 3 main Division championships. In Street Division and Mixed Division, the Street Tire Index doesn't come into play at all. In Modified Division, it is applied to all classes, so it cancels out. It only comes into play in the ROTY trophy (in the past), which is now the Novice Division.

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Thanks for the great explanation, Beau.

Where did you find the SMF-S PAX factor 0.840? I looked in the Supplemental Regulations and saw only the standard PAX factors.

How did the WSCC determine 0.985 for a 'street tire index'? There must be a reason for that specific number.

 

Rick Ruth, the man behind SCCA pax factors created the original 0.975 Street tire PAX adjustment for the 2013 season when RTR was introduced nationally in the SCCA. This factor was based on his extensive data. IIRC some clubs expressed issue with the 0.975 factor as it applies well to high concrete lots (Ex. Lincoln Nationals site) whereas asphalt or any low grip surface lots required something different, 0985 was later proposed by Rick (however I can't find the discussion at the moment). These alternate street tire pax factors are supplemental club rules. Due to our low grip surface at St. Andrews we opted for the 0.985 factor a few years ago.

 

Please note your car would not be legal for DSP or SMF with your described interior, all interior carpets, headliners and interior panels must be present as per the SP ans SM rules. the stripped interior you descrip falls under E-Prepared.

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Here's a different JDM question:

 

What if someone had a mid-90's miata that had the same specs as the USDM miata? Would it automatically go to JDM land or would it be classed the same?

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Jdm land. Not the same part numbers make the car. Steering on the other side means not the same. Emission rules differ, bumper rules differ. They put them there because of that.

It sucks but it's the way it is.

#modlife

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I hope to help bump the thread with some new info:

 

I think the rule book link doesn't work. I think this is the newest one?

 

http://cdn.growassets.net/user_files/scca/downloads/000/003/742/2015-5-19_SCCA_Solo_Rules_book_online_reduced.pdf?1432652746

Thank you for the bringing up this issue. I have updated the first post. The rulebook link you posted is correct for 2015.

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Verification of my reading:

 

JDM 2000 Subaru Impreza WRX STI

 

Would be Street Modified?

 

According to the Classificaiton Worksheet:

- OK: Brembos. Currently on stock brakes, but intend to put on the brembos (assuming the new wheels will clear them).

- OK: Front subframe brace. Currently not on car, but intend to put on

- OK: Aftermarket exhaust. Currently on car. Passed MB safety.

- OK: Tires: Yokohama Advan Sport v103 215/45/17 (What's the tire rating? 180?)

- OK: Engine displacement: 1990 cc

 

I believe the rest of the car is stock, specifically sway bars, springs, struts, front strut tower brace, block, turbo, fuel system, intake, intercooler, ecu, etc.

 

Other things I intend to do at some point:

- Tune: Once I find a good solution, I want to tune for local conditions (air, fuel, not looking for more power)

Your car would be classed as Street Modified due to the vehicle being a JDM RHD model. All the modifications you listed are legal for use in Street Modified (SM)

.

Hope to you see you out in 2015!

 

So based on this I've just been putting my car in SM. Riley was saying I might / should be in SMS, and that might improve my pax as well?

 

Based on the info below, I don't think my tire wear rating is below 180:

http://www.tirerack.com/tires/tires.jsp?tireMake=Yokohama&tireModel=ADVAN+Sport

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Hey Dan,

 

Locally you have 2 choices:

  1. You can run in the "proper" class (i.e. SM) with R-comps or any other tires you want. This would be in the Mixed Division. You would be subject to the "proper" SM pax of 0.870.
  2. If you are using street tires anyway (with a tread wear rating of >=140) you can compete in the Modified Street Tire Division. In that case you would be SMS with pax of 0.857. This is better for you as you gain an advantage.

The reason we have duplicate classes like this is that most of our local drivers don't bother bolting up R-comps and choosing option #1. If you travel to an autocross outside of Winnipeg, you'll likely find that #1 is the only option, so you'll be at a disadvantage if you're only running street tires.

 

Locally, since most of the guys just stick with street tires anyway, we created a place for them to play and still be competitive. We basically said "okay, all you guys who want to race on street tires in the higher categories, you can do so against each other but then nobody with R-comps are allowed in that division." And yes, we reduced the pax penalty on cars in this division, just so you can compare to other divisions and it would be somewhat close, or at least closer to what it should be (which is all theoretical anyway).

 

Now, since you're in the Novice Division, you compete against all novices regardless of division, so you could be up against SM guys with R comps and SMS guys with street tires. Your choice. If you are running street tires, you should definitely choose SMS.

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I was going to PM you but it says you can't receive any new PMs.

 

Thanks for getting back to me about the classifications and pax factors. I had always signed up as SM but most of my times were calculated as SMS.
 
Turns out Event 6, 9, and 10 were calculated in SM and my pax time should actually be lower :D.
 
If you guys could class me proper for those ones that would be great! I'll make sure all my registrations are SMS from now on. Thanks!

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I just want to confirm something for Street class...

 

Section 13.4 says "Wheel studs, lug nuts, valve stems (including pressure-relief types), and/or bolt length may be changed."

 

My assumption is that the change is not limited to saying within a certain type, i.e. my car uses lug bolts so I can change to any other lug bolt, but rather I can change my lug bolts to studs and lug nuts.

 

Now to find lug nuts that I want. Looking to ball seat, closed end with integrated washers that fit M14x1.5 threads...not sure if they even exist...and at a price point I'm willing to pay.

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Bmw guys do that all the time.

Look at the McGuard spline drive lugs. There what I used with an integrated washer.

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That is quite a common mod for 914s. It's a royal PITA changing a tire.

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Hmm ... really? There's a specific rule in SP [15.4.B] that specifically allows it. So I assume it's not legal until SP or higher.

 

Having said that, there's no performance advantage, so I don't think anyone here locally would protest. And probably not on the national level either, but you never know. Personally I think it's a brutal protest if it ever came up, so don't worry about it, but that's me. According to the exact wording of the rules, you might wanna double check if you're planning to go to Nats and win.

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was curious on what class ill be running this up coming summer, 2000 Honda s2000, lowered on coil overs, just bought 225-50-16 re 71 r square on ap1 rear wheel square setup, front sway bar, car has aftermarket exhaust atm but will most likely be going back to stock. Any help will be appreciated

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You can fit in STR or BSP-streets.  If your exhaust eliminates the cat, you go straight to BSP-streets.  

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