Classing Tutorial

[Bridgette]

I see that some people are having a hard time understanding the classing structure of Solo 2. I'll try to explain it a little bit.

Edit: Also try using the Milwaukee Regions's classification page which gives a couple of really good worksheets for classing you car. - DarkGift


You can figure out what class your car goes into by checking http://www.moutons.org/sccasolo/ but it's not easy to decipher. So here's some basic guidelines.

First lets start with some cliff notes to kick-start you down the road to understanding where your car fits.

Cliff notes

Stock Pretty much as from factory. Same size wheels as stock, any size tires that can fit under the wheel wells (no rolling of fenders!), any shocks, brake pads, alignment that can be achieved using manufacturer recommended methods, safety harness, any plugs and wires, any filter that will fit in the stock air filter box, any cat-back exhaust. R-compound tires allowed.

Street Touring S or X Lowered, any suspension mods, simple bolt on engine mods like header and CAI. Any wheels up to 7.5 inches wide (or 8? in STX) 225 max width tires. (245 for STX) 140 treadwear tires required. (Meaning no R-compounds) Must have the interior intact.

Street Prepared Same suspension freedom as Street Touring, more engine freedom than Street Touring, no max tire size. Interior must remain intact.

Street Modified The name kinda says it all in this class ?with some restrictions. Max N/A restriction of 6.0 liters, forced induction size limit of 3.0 OHC, or 4.0 for pushrod engines. Engine swaps must be from manufacturer, or from manufacturer affiliate (like Honda/Acura, Ford/Mazda, Pontiac/any GM line, etc.) Suspension is unlimited as long as it attaches to the original suspension mounts. Car may be lightened, but must retain most of the interior. (Taking out the back seat is okay, otherwise no stripping the interior!) Some rotary cars.

Street Modified 2 Same as above, for 2 seat cars or cars with engines up to 8.5 liters NA, or 4.0 OHC, 5.0 pushrod forced induction. (with weight restrictions) Also for rotary engine cars.

Modified and Prepared classes Non-streetable pure racecars. Tube frame, gutted cars.
Your car might be put in here if you have utterly stripped the interior. You will be getting your butt kicked if you find yourself with a daily driver in these classes.

End of cliff notes! Lets get into some detail now. If you found the class you think your car fits into in the cliff notes above, skip down to the class you think it fits into and check it out.

Stock: Your car will probably fall under stock if it conforms to the Midas rule. The Midas rule is "If you can get it done at Midas muffler, it's probably legal!"

*Any aftermarket airfilter that fit within the stock airbox or filter assembly.
*Any catback exhaust that conforms to the sound limits of the site we are using.
*Any alignment that your car can achieve using factory authorized methods. (No crash bolts, or camber plates, etc, unless factory authorized.)
*Any brake pads.
*Any wheels that are the stock size and width = or - 1/4 inch offset.
*Any shock absorber, as long as it has no more than 2 adjustments.
*Any gauges or "comfort and convenience" items. (Stereo's etc)
*Anything that was available from the factory on that exact year and model car. Dealer installed upgrades are NOT LEGAL. Any package upgrades must be done as a complete package! In other words, if your car had a sport suspension, but it only came with a sunroof and leather interior ... you must install a leather interior and sunroof to be 100% legal in stock!
*Harness, and/or harness bar. Harness bar may not be a chassis-stiffening device.
*Roll cage, can only be bolted in.
*Any front swaybar. (Okay, that's the oddball one!)
*Any DOT approved street legal tires. (This is why we use r-compounds. They are street legal.)
*Engine re-bore .20 over.
*Any oil filter
*Any oils.

If you think your car fits into Stock class, then follow this link to find out what particular stock class your car fits into:
http://moutons.org/sccasolo/Lists/2003/stockm.html (It may be a little out of date, but it should give you a good idea.)

Your car is a bit more modified than that?

Street Touring Super (STS) and Street Touring eXtreme (STX) are for small displacement coupes and sedans with simple bolt on modifications and street tires with a treadwear of over 140.

If your car is a normally aspirated sedan (four seats, four factory seatbelts, not sports car derived) of 3.1 Liters or less, or one of a few small turbocharged cars specified in the rules. STX engine displacement is 5.0 liters and allows stock forced induction (turbocharged or supercharged) up to 2 liters.
Street Touring allows anything allowed in Stock, plus (roughly) these modifications:

* Any shocks, struts, and springs, using original attachment points
* Any sway bars
* Any wheels up to 7.5" in width that fit over stock brakes
* Tires up to and including a width of 225, with a treadwear rating of 140 or greater. (8? wide wheels & 245 width tires for STX)
* Strut bars/braces as allowed in Street Prepared.
* Exhaust system downstream of catalytic converter(s) (Pre-cat?s may be removed and high-flow cat?s are permissible in STX)
* Short throw shift kits
* Spoilers, body kits, rear wings, etc.
* Pedal kits and other interior cosmetic accessories
* Alternate brakes pads and linings
* Any fully padded and upholstered front seats, must weigh over 15 lbs. (As of 2004 they do not have to recline)
* Removal of factory trim (rub strips, emblems)
* Alternate steering wheels of any diameter, otherwise meeting Stock rules
* Cross drilled and/or slotted brake rotors
* Alternate air cleaner enclosures
* No limited slip differentials except factory viscous coupler type units (STX allows LSD?s and AWD)
* Stock brake calipers/drums
* Fenders may not be cut or flared (but specific modifications for tires OK)
* Emission-legal headers
* Emission legal modifications to Engine management system, either electronic or mechanical, but not both.
* Engine and transmission must remain unmodified, including emissions equipment
* Relocated battery
* Clutch must be stock, or stock replacement.


The following vehicles are allowed in STS despite the fact that they are turbocharged:

Volkswagen Golf/Jetta/Beetle/Passat 1.8T
Volkswagen Jetta TDI, Golf TDI
Audi A4 1.8T, non-Quattro
Mazda 323 GTX(awd)
Mazda 323 GT
Volvo S40 and V40

The following cars are expressly forbidden from STS/X
Lancer EVOVIII
WRX STi
BMW M3
Camaro SS
RX-8
Viper (duh)
Two seat sport cars.

Note that r-compound tires are forbidden in this class.

Still not your car? ? Street Prepared might be where your car fits then.

Street Prepared is a lot like Street Touring but allows some engine modifications. All the stock class rules apply, plus most of the Street Touring rules. You may modify the engine? Engine modifications like, carburators, replacement intake manifolds, anything up to the head. Porting up to one inch inside the head. Emissions controls may be removed. No wheel width restriction and R-compound tires may be used.

* You may update or backdate parts or components (engines and transmissions must be UD/BD as a whole unit) from the same vehicle on the same line in the Street Prepared index in the Solo rulebook.
Alternate computer control modules may be used whenever an equivalent change to the conventional system is allowed. For example, alternate computer module control of ignition settings or fuel injection is allowed. Direct turbocharger boost control by alternate computer control is not, since there is no equivalent mechanical allowance.
* Air conditioning systems may be removed in whole or in part. This rule should not be interpreted to allow modification of the heater system.
* Welded roll cage
* Fuel cell
* Pretty much any suspension as long as it attaches to original mounting points and is as stock intended. (Like if it came with coil springs, it still has coil springs, but they are now coilovers, or had leaf springs, but now has more, or are re-arched, etc.)
* Relocate battery
* Water injection
* Any clutch
* Any LSD

This link will show you which Street Prepared class your car would fall into: http://www.moutons.org/sccasolo/Lists/2003/stprepm.html

More modified than that?

Street Modified and Street Modified 2 are kind of ?anything goes? classes. There are restrictions, but it?s still a whole lot more open than any of the other classes out there. All of the rules from Stock, Street Prepared and Street Touring apply. (except the ones that conflict of course!)

VEHICLE ELIGIBILITY
*STREET MOD (SM): All sedans/coupes (models which were originally equipped with a minimum of four seats, four factory seat belts, not sports car based).
Sample Vehicles:
* Chrysler: Neon, Stratus/Breeze
* Ford: Contour, Escort, Probe, Mustang
* General Motors: Cavalier, Sunfire, Camaro
* Honda: Civic, Accord, Integra
* Mazda: Protege, MX-6, 626
* Nissan: Altima, Sentra
* Toyota: Celica, Corolla, Camry
* VW: Golf, Jetta
Sample Excluded Vehicles:
* Porsche, all
* Honda CRX
* RX-7 TT
* Miata, all
1. STREET MOD 2 (SM2):
a. All two seater cars, not excluded below.
b. All SM eligible sedans/coupes excluded from SM for failure to meet weight and/or displacement limits.
c. Excluded Vehicles:
* Lotus (all)
* Two seater cars not eligible for Street Prepared Category
18.1. ALLOWED MODIFICATIONS
A. All Street Touring modifications are allowed.
B. All Street Prepared modifications are allowed.
C. Section 15.6(Prepared Category, Brakes)
D. Drivetrain and related components (induction, ignition, fuel systems, etc.) are unrestricted except for the following limitations:
1. Engine must be from the same manufacturer as the body (Toyota/Lexus, Nissan/Datsun, Honda/Acura, etc.) Badges that exist as marketing aliases for the manufacturer (Honda/Acura, Toyota/Lexus, Nissan/Datsun) will be recognized as equivalents. Swaps involving makes related only at corporate level (e.g. Ford/Volvo, Renault/Nissan, Chrysler/Mercedes) are not recognized as equivalents. Models produced as a joint venture between manufacturers may utilize any engine from any partners in the joint venture, provided that an engine from the desired manufacturer was a factory option in that particular model (e.g. Eagle Talon available originally with either a Mitsubishi or Chrysler engine, may use any motor from Chrysler or Mitsubishi).
Maximum engine displacement:
- Forced induction -
* 3.0L (OHC engines)
* 4.0L (pushrod engines)
* Normally aspirated -
* 6.0L
- Rotary engines (all) -
* 1.5L
2. Must comply with section 3.6.B regarding fuel.
E. Suspension components are unrestricted as long as they use the original attachment points. Brakes are unrestricted.
F. Subframe connectors are allowed, but each connector must be attached individually without any lateral components attaching the two longitudinal frame rails. Subframe connectors may be bolted or welded
G. The firewall, roof, doors, rear quarter panels, floor pan, trunk lid (if any) or rear hatch (if any) must remain stock. Holes may be drilled to allow attachment of body kits, etc. This specifically allows replacement hoods, fenders, wings, front & rear fascias, side skirts, and fender flares as per Section 14. Body panels may be attached with removable (e.g., Dzus) fasteners.
H. Except as noted by these rules and the referenced rules, vehicles must be as originally delivered including all road going components such as lights, wipers, interior, heater, etc.
I. Rear passenger seat(s) does not need to be retained.
J. Wings may only be attached to the rear deck/hatch area and may not extend more than six inches beyond the widest part of the bodywork on either side.
K. Any minor modification, intended to allow or facilitate any allowed modification, is permitted as long as it does not provide any intrinsic performance benefit in and of itself, does not provide a weight reduction of more than 1 lb., and is not explicitly prohibited elsewhere within these rules. This rule is intended to allow minor notching, bending, clearancing, grinding; the drilling of holes; affixing, relocating, or strengthening of brackets; removal of small parts, and similar operations performed in order to facilitate the installation of allowed parts or modifications. Competitors are strongly cautioned to make the minimum amount of modification required to affix a given part, and not to make unduly tortured interpretations of this rule. Modifications to the firewall in order to allow for increased engine setback, and any modification that changes the location of of a suspension pickup point, are explicitly forbiddden.
18.2. MINIMUM WEIGHTS
A. Street Mod (SM)
1. Up to 3.0L, naturally aspirated, OHC engines
Up to 4.0L, naturally aspirated, pushrod engines
a. FWD: 1800 pounds
b. RWD: 2200 pounds
c. AWD: 2400 pounds
2. Up to 3.0L, forced induction, OHC engines
Up to 4.0L, forced induction, pushrod engines
a. FWD: 1900 pounds
b. RWD: 2400 pounds
c. AWD: 2600 pounds
3. Up to 3.01 to 6.0L, naturally aspirated, OHC engines
Up to 4.01 to 6.0L, naturally aspirated, pushrod engines
Up to 1.5L, rotary engines, all
a. FWD: 2000 pounds
b. RWD: 2500 pounds
c. AWD: 2700 pounds
B. Street Mod 2 (SM2), two seat vehicles and underweight SM vehicles
1. Up to 4.0L, naturally aspirated, OHC engines
Up to 5.0L, naturally aspirated, pushrod engines
a. FWD: 1500 pounds
b. RWD: 1900 pounds
c. AWD: 2100 pounds
2. Up to 4.0L, forced induction, OHC engines
Up to 5.0L, forced induction, pushrod engines
a. FWD: 1600 pounds
b. RWD: 2100 pounds
c. AWD: 2300 pounds
3. Up to 4.01 to 8.5.0L, naturally aspirated, OHC engines
Up to 5.01 to 8.5L, naturally aspirated, pushrod engines
Up to 3.0L, rotary engines, all
a. FWD: 1700 pounds
b. RWD: 2200 pounds
c. AWD: 2400 pounds
C. Street Mod 2 (SM2), over-displacement SM vehicles
1. All types/displacements
a. FWD: 2000 pounds
b. RWD: 2500 pounds
c. AWD: 2700 pounds


is your car still more modified than this?

Wow! You need to contact someone in the URSCCA to help you classify your car in one of the Modified or Prepared classes then.

This is by no means the end-all be all of classing, it is provided as a means to help you correctly classify your car. It my contain errors, but it should be a pretty good guideline to get you on your way to correctly classing your car.

Good luck!
Bridgette Olson,
2004 Utah SCCA Secretary.