STOCK category has nine classes topped by Super Stock and then A through H Stock. SS is where those 'Vettes and Vipers go. HS may be the home of Toyotas and Hyundais. In between come the Miatas and Mustangs, Porsches and Pontiacs, Nissans and Neons. It's not really the "nothing" category – there are things you can do, but they mostly involve replacing parts with better parts (tires, shocks, etc.) than actually modifying the car.

      STREET PREPARED has six classes – ASP through FSP. More is allowed to be done to the car, but they are still basically (if barely) streetable and should be capable of being licensed for street use.

      STREET TOURING is essentially a re-thinking of the next step up from stock. It goes a different direction from Street Prepared and probably falls between Stock and SP in its prep levels. ST and STR are the primary classes for sedan-type vehicles and roadsters on DOT treadwear 140+ street tires, while STS (“Sport”), STX (“eXtreme”) and STU (“Ultra”) is the same idea but allowing some additional cars and some other modifications. Salina Region has added a local class, STO ("other") which permits any car on street rubber to run. It is a great starter class, three classes actually, STO4, STO6 and STO8 depending on engine.

     STREET TOURING OPEN While not an official class it was developed by Salina Region and is our most popular class.  STO classes are 'run what ya brung' classes permitting cars which may or may not be fully compliant with Stock, Street Touring or Street Prepared rules, but running on D.O.T. tires meeting current Street Touring Rules (minimum UTQG treadwear rating of 140 or greater).

 STO4
     All 4 naturally aspirated engines with 4 or less cylinders.

 STO6
     All naturally aspirated engines with 5 or 6 cylinders.
     All naturally aspirated rotary engines.
     All forced induction engines with 4 or fewer cylinders.

 STO8
     All naturally aspirated engines with 7 or more cylinders.
     All forced induction engines with 5 or more cylinders.
     All rotary engines with forced induction.

      STREET MODIFIED is an even newer category, aimed primarily at the new wave of modified imports that are becoming very popular. Engine swaps are allowed as long as the engine comes from the same manufacturer (a 6-cylinder Honda in a Civic, for example). There is SSM, SM, and SMF (“Super,” Basic and FWD) for different groups of cars.

      PREPARED has been around as long as Stock, since the Solo program began. There are six classes from X Prepared then CP to GP. These are full-out race cars built off production chassis. The concept originally began with Production- and Sedan-class road racers and most look like those type of cars. They're highly modified, run on racing slicks, and come in on trailers because there is no way they are street-legal. CP, which is the class for Mustangs, Camaros, etc., is one of the most popular classes in the sport.

      MODIFIED also has been around from the beginning but has grown to eight classes, AM to FM, plus Formula SAE and Karts. AM, BM, CM and FM are mostly formula and sportsracer chassis, including everything from homebuilt specials to full-out Formula Atlantics to wild-winged A-Mods that are almost whatever their builders can imagine. DM and EM are for wildly modified cars that began life as a production chassis. Formula SAE is the 600cc open-wheelers built to the collegiate F/SAE rules

      KARTS also are technically in the Modified category but are their own animal. SCCA has Formula 125, which is basically any shifter kart up to 125cc or any clutch kart up to 100 cc or so. Karters have to wear leathers or skid suits because they are the only classes that do not require seatbelts. There also is a Junior Kart program which permits drivers age 8-15 to compete using 5 hp karts. Junior Kart participants must be SCCA members.