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SOCAL SCALE CAR RULES FOR 2003 SEASON

The rules that SoCal USRA racing follow are the National USRA rules, using the 2002 USRA rulebook as the base, and then the 2003 rulebook once it is available. The rules below are specific to SoCal racing, and override rules found in the National USRA Rulebook if there is a conflict.

During 2003 the SoCal rules committee will publish a complete set of SoCal rules, which will then become the rules for all SoCal USRA races from that time on.

GENERAL INFO:
For NASCAR, GT-1 and 4 ½ NASCAR the distance from the top of the rear axle to the bottom of the chassis cannot be less than .345 inches.

Minimum rear clearance for GT-1 and GT-12 cars will be specified by the track owner.  Refer to the information page for each race to see the clearance rule.  Unless stated otherwise, GT-1 will use 1/16 rear clearance and GT12 will use 1/32 clearance.

For all classes, 3/32 rear axles may be used. Experts may use any gear pitch. Amateurs may only use 64 pitch.

C Can motors for all classes. Experts may mix and match any of the approved components. ie you may run a kelly can with a RJR endbell with mura hardware and koford magnets. Amateurs may not mix and match components, apart from magnets.

GROUP 10 4" NASCAR
Same as described in 2002 USRA National rules for Group 10 4 inch NASCAR with the following exceptions:

1. Only 3/32 axles allowed
2. Only 64 pitch gears allowed in amateur class
3. Bodies must still have 1/8" front and rear bumpers
4. New for 2003 - Maximum rear spoiler height measured from the tech block to the top of the spoiler with the car sitting on a tech block (car must have legal 1/16” clearance) will be 1 3/8”. There will be no roof height measurement taken.
5. Experts may use the new Kelly 16D setup.
6. Big diameter armatures are legal for both Amateur and Expert racing

Click here to see the approved parts for the 4" NASCAR class, including chassis, bodies and motors.

4 1/2" NASCAR:
Chassis: Must be commercially available and USRA approved. Must be made from stamped and formed metal material only. Click here to see the approved chassis.
No modifications allowed except for the following:
May solder or glue oilltes and motor in place;
May add lead weight;
May modify motor bracket for motor installation but must retain a portion of bracket.
May add tape to chassis.
May use light weight replacement pans and center sections.
No oilite modifications.
May use offset oilites;
May add spacers between pans and center section.
May add a 1 inch motor brace and an upright brace. 
Pin tubes are allowed.
May only use production extenders on the chassis they were produced for.
May remove front wings for extender front wheel clearance only.

Motors: Balanced 16d Group 10 motor as described in 2002 USRA National rules for production 1/24 Stock car. No ball bearings. These are the same motors as used in SoCal 4" NASCAR racing. Click here to see a list of the approved motors. (Kelly 16D setups are legal for Experts only)

Body Specifications: Champion 4 1/2 NASCAR bodies only, part numbers 255,256,257 (Taurus) ,258 (Pontiac) ,259 (T Bird),260 (Monte Carlo). 
1/4 inch front bumper.
1/8 inch rear bumper.
Maximum height of rear spoiler is 1 5/8 inches measured with the car sitting flat on a techblock. 
No roof height requirement.
Click on the diagram for a larger view (Opens in a new window).
NEW FOR 2003 - All cars must run Slixx decals to be eligible to enter the race. At least the numbers and main sponsors logos must be present.

Axles/Tires/Wheels:
Front axle min. diameter 3 / 32"
Rear axle diameter 3/32".
Front wheels min. diameter .675"
Rear wheels min. diameter .750.
All tires front and rear must be black rubber.
Min. front width .400"
Max. rear width .810" including rubber over-hang.
Solid front axles only, no stubbies.
Independent rotating fronts allowed.
Front axles may be soldered to chassis but tires must rotate.
May add oilites to front axles for soldering support only.
May add clear coating to fronts.

Gears:
Any gear ratio allowed.
Amateur racers must use 64 pitch pinions and spurs, Experts may use any pitch.
May solder pinion. 

Clearance:
Car including chassis and gear must have .063" rear clearance.

Approved Chassis:
Click here to see the approved chassis for this class

1. Amateur class may only use 64 pitch gears.

Bodies now follow National rules. 
Body must be trimmed along the cut line.
New for 2003 The back of GT 1 bodies may now be cut out. The sides of the body must remain intact all the way down to the cutline, and at the back some material must be maintained at each side of the cut out. The cutting can be done the same as has been std practice for GT 12 bodies in recent years.

Click here to see the approved parts for the GT1 class, including chassis, bodies and motors.

GT-12
Same as described in USRA National rules for GT-12 with the following exceptions:

1. Ball bearing allowed in can end of motor
2. ToyTech Cadillac is legal for SoCal USRA only
3. Amateur class may only use 64 pitch gears

Click here to see the approved parts for the GT12 class, including chassis, bodies and motors.