Rallcross Classes Explained
Stock AWD Category
1. All vehicles must be equipped as from the manufacturer, with only factory installed and port‐installed option packages. Options that were only part of a package must be present with the entire package. Complete option packages may be installed after purchase of the vehicle.
2. Tires must be U.S. Department of Transportation (DOT) approved and display the applicable DOT symbol and Tire Identification Number (TIN) label. Tires with the equivalent Canadian DOT and TIN labels are allowed on Canada‐ registered vehicles at Regional events. Tires marked “For competition only”, “Not for street use” or similar are not allowed. No part of the tire may be modified or altered from its original form, either through addition or subtraction, other than normal wear. Retreaded, recapped, and remolded tires are not permitted. No studded tires are permitted at National events unless ice or snow is present; Regional and Divisional events may allow studded tires any time. Studded tires may not be homemade using bolts or screws. Only street‐legal studs are allowed. Alternate tire sizes are allowed but tires may not interfere with any parts of the car (fenders, fender liners, suspension, etc.). Inner tubes are considered an integral part of the tire.
3. Any air filter may be used, but it must fit in the stock location.
4. The addition of protective equipment is allowed with the following exceptions:
a. The modifications must only provide protection to the car and/or occupants and provide no performance advantage. Examples of allowed protective equipment include skid plates to protect underbody components and to protect lower front fascias from ground contact, mud flaps and bolt‐on fender flares to protect paint from gravel damage, driver restraints/harness belts and roll cages/bars to protect occupants, and strut caps to prevent failure of strut mounts. Mounting hardware for bumper covers, fascias, body panels, undertrays, and trim pieces may be replaced with alternate components. Any alternate mounting hardware shall only serve to reinforce the mounting mechanism of the panel or body part and shall not provide any performance advantage or weight reduction. Examples of non‐allowed modifications that provide a performance advantage include larger radiators to reduce engine temperatures, oil catch cans to reduce oil in the intake system, vents/scoops to improve cooling or intake airflow, additional ducting to improve engine or brake cooling.
b. Mud flaps must be flexible.
c. Skid plates protecting suspension and drivetrain components may only be made from metal, composite materials or plastic derivatives. Skid plates may supplement or replace OEM skid plates or underbody protection.
d. Driver restraints and roll cage may be added. Modification of interior components to the minimum extent necessary for the proper installation of driver restraints and roll cage is permitted.
e. Additional or replacement hood and trunk latches are permitted. All latch systems must be secure.
5. Dress‐up and convenience items which do not give a performance advantage, reduce the weight of the car or weigh less than the replaced standard part they are replacing are allowed (i.e. shift knobs, pedal covers).
6. ABS and/or traction control systems may be electronically/electrically disabled but not removed.
7. Vehicle lights may be replaced with alternate bulbs and housing. Auxiliary lights may be added. The total number of lights shall not be less than standard.
8. Any brake pads may be used.
9. Fuel may be any type of unleaded, ethanol, or diesel/biodiesel fuel commonly available at the pump. Alternative fuels must be pre‐approved by the event Safety Steward prior to the event. No other alcohol fuels or nitrous oxide are allowed.
10. Any clutch disc or pressure plate may be used provided it fits all the other unmodified, stock components.
11. Exhaust systems from the catalytic converter back may be removed or replaced with the following requirements:
a. The exhaust must exit to the rear of the driver;
b. The exhaust must comply with local noise restrictions.
12. Any type wheel may be used provided it complies with the following:
a. Wheel diameter may be increased or decreased one inch (1”) from the OEM wheel;
b. Wheel width may be increased or decreased one‐half inch (0.5”) from the OEM wheel;
c. Wheel offset (backspace) must be within 0.394" (10mm) of the OEM wheel offset. Wheel spacers are considered part of the wheel;
d. Extended length wheel studs/bolts are allowed but the type of fastener (bolt or stud) may not be changed.
13. Shocks/dampers may be replaced with unmodified OEM or unmodified, mass‐producedaftermarketreplacementunitsintendedbythe manufacturer for the specific year, make and model used. Rebuilds are allowed but only if the shock/damper is rebuilt to its original specifications (i.e. no re‐valving). The stock spring must be used as it was on the OEM unit. The spring perch must be factory welded to the damper or use the exact attachment method and position as OEM. Adjustable dampers are only allowed if the OEM unit was adjustable and must retain the same number of adjustments or fewer as OEM. Remote reservoir shocks are only allowed if they are exact OEM units.
14. One sway bar may be added, replaced or removed. A replacement sway bar may serve no other purpose than originally intended by the vehicle manufacturer. In the case where the sway bar is also a suspension locating link, stock geometry and methods of attachment must be maintained.
15. Any wheel alignment settings may be used provided the settings can be accomplished within the unmodified adjustment range as delivered from the factory. Any alignment techniques allowed by the factory service manual from the vehicle manufacturer may also be used.
16. Aftermarket replacement batteries are allowed provided they are the same group size and location as originally equipped.
17. Spare tires, tools, jacks, and any related covers may be removed.
18. Audio system components may be replaced with alternate components intended for the application (i.e. factory head unit may be replaced with aftermarket single‐din head unit).
19. Tire pressure monitoring systems (TPMS) may be disabled. Altering the signal to the TPMS is permitted.
20. Vehicles may add one rear trailer hitch/receiver that may serve no other purpose. Factory tie downs and cosmetic pieces may be modified or removed only to the extent necessary to facilitate hitch installation. Complete or partial removal of the hitch is allowed for competition, provided it does not result in a reduction in weight compared to the unmodified standard configuration.
21. The installation of oil catch tanks or oil separators is allowed provided the PCV system remains functional.
Prepared AWD Category
1. All Stock category modifications are allowed.
2. Any sway bars and their mounting may be used or removed.
3. Any brakes may be used.
4. Exhaust systems from the cylinder head exhaust ports back may be replaced with any material with the following requirements:
a. The exhaust must exit to the rear of the driver.
b. The exhaust must comply with local noise restrictions.
c. Functional catalytic converter(s) are required on vehicles equipped with catalytic converter(s) as original equipment. Any high flow catalytic converter(s) are allowed. Multiple catalytic converters may be replaced by a single unit. The inlet of the single replacement converter may be located no further downstream than 6" along the piping flow path from the original exit of the final OE converter. Vehicles not equipped with a catalytic converter as original equipment are not required to have one.
5. The intake system upstream from the throttle body may be replaced with any material. Forced induction components cannot be changed or added (turbochargers, superchargers, intercoolers). Turbocharger boost regulation systems, either electronic or mechanical, may be modified or replaced. The pulley on the supercharger may be replaced with an alternate size along with the supercharger drive belt.
6. Short shift kits are allowed.
7. Front and/or rear strut tower bars are permitted.
8. Any dampers may be used. Damper attachment points on the body/frame/subframe/chassis/suspension member may not be altered. This installation may incorporate an alternate upper spring perch/seat and/or mounting block (bearing mount). No damper may be capable of adjustment while the car is in motion, unless fitted as original equipment. MacPherson strut equipped cars may substitute struts, and/or may use any insert. This does not allow unauthorized changes in suspension geometry or changes in attachment points (e.g., affecting the position of the lower ball joint or spindle). Threaded collars and camber plates are allowed.
a. Camber kits, also known as camber compensators, may be installed. These kits consist of either adjustable length arms or arm mounts (including ball joints) that provide a lateral adjustment to the effective length of a control arm. Alignment outside the factory specifications is allowed. The following restrictions apply:
1. On double/unequal arm (e.g. wishbone, multi‐link) suspensions, only the upper arms OR lower arms may be modified or replaced, but not both. Non‐integral longitudinal arms that primarily control fore/aft wheel movement (e.g. trailing arm(s) or link(s) of a multilink suspension) may not be replaced, changed, or modified.
2. On arm‐and‐strut (MacPherson) suspensions, adjustable camber plates may be installed at the top of the strut and the original upper mounting holes may be slotted. The drilling of holes in order to perform the installation is permitted. The center clearance hole may not be modified. Any type of bearing or bushing may be used in the adjustable camber plate attachment to the strut. The installation may incorporate an alternate upper spring perch/seat and/or mounting block (bearing mount).
3. On swing or trailing arm suspensions, the main arms may not be modified or replaced, but lateral locating links/arms may be modified or replaced.
4. The replacement arms or mounts must attach to the original standard mounting points. All bushings may not be moved or relocated on the arm, except as incidental to the camber adjustment. The knuckle/bearing housing/spindle assembly cannot be modified or replaced.
b. Springs may be replaced, but they must be of the same type and use original mounting points.
9. Electronic engine controls may be modified or piggybacked, but not replaced.
10. Any tire is allowed except home‐built studded tires.
11. Any front seat may be used, provided the seating surface is fully upholstered. This does not permit the substitution of a passenger’s seat with a child or miniature seat of any type. Any substituted passenger’s seat must be sufficiently large and strong to be capable of adequately accommodating an adult, such that it could be used as the driver’s seat. Cars may have no fewer than the original number of seats. Seat belts are required in all cars; however; the number of attachment points may not be less than originally equipped. Installation of shoulder and lap belts is strongly recommended. Additional belts must be installed per the belt manufacturer's recommendations.
12. Mounting of suspension, steering rack, engine, transmission, differential, and body/frame and motion control of engine and transmission:
a. Any non‐metallic bushing, including any suspension, steering rack, engine, transmission, differential, and body/frame mount bushing, is allowed but the replacement must be non‐metallic and attach to the original factory location without modification.
b. Any device (pitch stop, dog bone, bobble strut, etc.) to control motion of the engine and or transmission mount may be replaced. All of the original mounting locations must be used and cannot be modified. Hardware may be changed as required for proper installation. This does not allow for subframe replacement.
13. Wheels are unrestricted. Wheel bolts may be replaced with wheel studs and lug nuts.
14. On carburetor‐equipped cars, any bolt on intake manifold or carburetor may be used. Any air filter system and associated parts may also be used.
15. Vehicles may substitute any differential with a mechanically governed limited slip or locking unit of an alternate type. This includes spools and welded stock differentials. This does not allow the use of a differential with external controls (electronic or otherwise) to regulate slip or locking. Differentials must be contained in a stock unmodified housing/third member with stock or optional ring and pinion ratios available for the specific model, body, and year of the vehicle only.
16. Batteries may be substituted with any type. Relocation of the battery or batteries within the engine compartment or trunk area/luggage compartment behind the rearmost seats is permitted. Longer battery cables may be substituted to permit relocation and holes may be drilled to accommodate mounting of the battery and cables.
17. Accessory drive pulleys and belts may be replaced.
18. Any clutch disc, flywheel or pressure plate may be used.
19. On automatic transmission vehicles, any torque converter may be used.
20. Addition of rear wings and hood scoops/vents is allowed provided that either 1) it is a production part which is standard or optional equipment of a US model of the vehicle or 2) it is listed in the vehicle manufacturer's US accessory catalog for that vehicle for normal highway use. Parts must be installed as directed by the manufacturer. Exact replicas (including weight) from alternate sources are also permitted.
21. Engine cooling radiators may be replaced with alternate parts subject to the following restrictions:
a. Radiator core dimensions (width, height, thickness) must be no smaller than the standard part.
b. Radiator must mount to OE radiator mounts.
c. Fluid capacity and dry weight of the radiator must be no less than that of the standard part. Installation of an alternate radiator may serve no other purpose (e.g. to allow a cold air intake passage). In addition, the engine fan and fan shroud (unless it serves another purpose, e.g., as an alternator/generator mount) may be removed, modified or replaced. Electrically driven fans are allowed.
22. Oil cooling radiators for engine, transmission, power steering, or differentials may be added, modified, or replaced with alternate parts providing they and their installation serve no other purpose, and subject to the following restrictions:
a. Fluid capacity and dry weight of any radiator being modified or replaced must be no less than that of the OEM standard part.
b. Radiator(s) and their lines must be securely mounted, reside in the engine bay area, or the general location of the OEM part being replaced or modified. No lines may be routed through the passenger compartment.
c. No body parts or structure may be altered in any way, except for the minimum holes to facilitate mounting brackets and fluid lines, for installation.
23. Alternate steering wheels and their attachment mechanisms are allowed.
24. Non‐metallic fender/wheel well liners may be modified or removed. Ground‐‐facing non‐metallic shields beneath the engine compartment may be modified or removed, provided they are forward of the passenger compartment and not integrally molded to the front bumper or valance.
25. Fenders may not be cut or flared but the inside lip may be rolled to gain additional tire clearance. The outer fender contour may not be changed.
26. Auxiliary lights (commonly called fog lights) may be removed. This does not allow the removal of turn signals, side markers, brake lights, daytime running lights, or headlights.
Modified AWD Category
1. All Prepared category modifications are allowed.
2. Any electronic engine controls may be used.
3. All non‐essential components may be removed, replaced or relocated for the purpose of weight reduction or with the following requirements:
a. The shape of the body must remain recognizable as that of the manufacturer’s make and model.
b. The body must be made of a fire resistant material.
c. Structural strength of the vehicle may not be reduced or compromised.
d. Doors, hoods, trunk lids, sunroofs, hatchbacks, etc., need not function as originally designed; however, the driver door and passenger doors (if a passenger seat is present) must maintain sufficient functionality to allow safe ingress/egress. Doors must latch securely and must be operable by a self-returning mechanism on both the inside and outside of the door. Door latches must require deliberate movements to operate and not operate with inadvertent contact. Grilles and trim pieces may be modified, removed, or replaced with replicas of alternate material. Bumpers not integral to the bodywork, and their associated mounting hardware, may be modified or removed. Bumpers integral to the bodywork may be modified or replaced with replicas of alternate material. Modified or replica bumpers must be of similar shape as standard components, and not confuse the identity of the vehicle. Lights may be modified or removed, provided any remaining openings must be covered with a wire mesh screen or panel of fiberglass, metal, or similar non‐flammable material. Side mirrors may be removed or modified.
e. Fenders and doors may be modified or replaced but not removed.
f. Side and rear windows may be removed or replaced with Lexan or equivalent; however, a convertible hardtop must retain the OEM rear window. Windshield may be replaced with Lexan or equivalent with addition of a full roll cage built to SCCA Improved Touring specifications or better.
g. The interior components may be completely removed and/or replaced. Any edges created by these modifications that the driver or passenger may contact must be properly insulated to prevent injury.
h. Roof panels must be metal of at least the same thickness as original. Sunroof panels may be replaced with sheet metal of at least the same thickness as an original roof skin without sunroof. Inner roof structure may only be modified with addition of a full roll cage built to SCCA Improved Touring specifications or better.
i. Aerodynamic devices, including wings, splitters, spoilers and spats, may be added, removed or modified, and any such devices used must be securely mounted to the vehicle.
j. A non‐OEM hardtop of a type substantially similar to the shape, design, construction, and weight of the OEM hardtop may be used if the vehicle is equipped with a roll bar built to current SCCA Time Trials specifications or better or a roll cage built to current SCCA Improved Touring specifications or better.
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, 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.
4. Any eligible (per Section 3.1) log booked race car or car currently legal for stage rally competition in other sanctioning bodies may run in its appropriate Rally Modified class regardless of whether it meets the Rally Modified rules.
5. Any engine may be used but must be internal combustion. Production‐ based hybrid vehicles (e.g. Toyota Prius) and production‐based electric vehicles (e.g. Nissan Leaf) are allowed, but electric power plant components and wiring shall not be altered or modified.
6. Any drive train may be used
7. Any suspension and steering components may be used. This allows changes to all components and geometry.
8. Additional chassis braces and seam welding are permitted.
9. Any fuel system may be used provided gasoline, ethanol or diesel fuel is used. Any non‐stock fuel cell, filter or pump located in the passenger compartment must be shielded by a metal bulkhead. Any fuel lines running through the passenger compartment must be of metal or metal braided construction.
10. Exhaust systems may be replaced with any material with the following requirements:
a. The exhaust must exit to the rear of the driver.
b. The exhaust must comply with local noise restrictions.
c. No catalytic converter is required.
11. Engine cooling systems are unrestricted.
12. Vehicles may be converted from LHD to RHD and vice-versa.
Two Wheel Drive Category
....all two wheel drive cars.