If this rulebook does not specifically say that you can change/modify/add something, then you must consider that the change/modification/addition is illegal. The intent of this division and its rules are to create and maintain a safe, competitive, and affordable racecar.  A modification to the S2 car that deviate from how the supplier initially presents the car is not permitted.



1. Battery:

(a) Only a lead cell or gel cell battery may be used.

(b) Minimum dimensions are 6” wide x 10” long x 7” tall.

(c) Car must run 12-volt electrical system.

(d) Battery must remain in its stock location and securely mounted.

(e) The original stock battery bracket may not be altered or moved.


2. Body:

(a) The only approved body is the Five Star S-2 Sportsman body.

(b) All panels must be run as produced by Five Star Race Car Bodies.

(c) Body must remain mounted to original body specifications and dimensions.

(d) Body must fit SRL template set.

(e) A-post windows must be 10” long maximum.

(f) No excessive trimming of body parts.

(g) Maximum front nose splitter width cannot exceed 75”.

(h) Body mounts and bumpers must be ran as supplied by SRL S2 supplier.


3. Brakes:

(a) All brake parts must remain stock size, shape, weight and material.

(b) Front and rear brake calipers must be stock GM replacement only.

(c) Brakes must be operational on all four wheels.

(d) No proportioning valves allowed. Brake bias adjuster OK.

(e) Only magnetic steel brake rotors allowed.

(f)  Front brake rotor must be minimum .900 x 11.75”

(g) Rear brake rotor must be minimum .800 x 11.75”

(h) Brake rotor must be vented type.

(i) No drilled or scalloped brake rotors allowed.

(j) Master cylinders must be Wilwood 260-6765 and 260-6766.

(k) No brake cooling fans allowed.

(l) No brake ducts or holes allowed in nose.


4. Car Number:

(a) Must have readable number on sides and roof.

(b) Series sponsor decal must be displayed across front window, and front fenders and forward part of door reserved for series contingency sponsors.


5. Chassis:

(a) Absolutely no modifications of the chassis will be permitted.

(b) Chassis must be raced as produced by SRL approved manufacturer.

(c) No altering pick up points on chassis.


6. Clutch and Flywheel:

(a) Flywheel must be 153 tooth OEM magnetic steel only (minimum 16#).

(b) Clutch disc must be magnetic steel (minimum 2.5#).

(c) Pressure plate must be magnetic steel (minimum 13#).

(d) 10.4” stock single disc diaphragm clutch only.

(e) Clutch master cylinder must be a Wilwood 260-1304.


7. Driveshaft:

(a) Must be 2.75” x .060 magnetic steel only.

(b) Must have solid tube yokes.

(c) Must use magnetic steel u-joints.

(d) Driveshaft must be painted white.

(e) Minimum weight is 14#.


8. Engine:

(a) GM 88958602 factory sealed break away bolt engine only.

(b) All engine components must be stock GM only including valve springs, rocker arms and balancer.

(c) After an engine has won three main events in one season, that engine may be purchased by any registered S2 race team that is in the top ten in the current point standings at the conclusion of an event.  Price will be current retail price plus 10%.


(b) Carburetor

(1) Holley 3310C is the only approved carburetor.

(2) Primary jets and power valve may be replaced with OEM type.

(3) Choke flap and linkage mechanism must be removed

(4) No other modifications allowed.

(5) Secondary diaphragm spring must remain stock.

(6) External vacuum ports must be plugged.

(7) Carburetor is subject to exchange by tech officials.


(c) Ignition

(1) Stock GM HEI Distributor only.

(2) Ignition module must remain stock.

(3) No billet distributors allowed.

(4) Stock GM distributor cap, rotor and coil only.

(d) Air Cleaner

(1) Standard metal air filter housing only.

(2) Air filter element must be 4”X14” paper.

(3) No air diverters, shields or coatings allowed.


(e) Mounts

(1) Engine must be centered in chassis.

(2) Minimum crankshaft height is 12.5”.

(3) Transmission mount must remain stock.


(f) Heat Shields

(1) No heat shields allowed on valve covers.

(2) No heat shields allowed on distributor.

(3) No heat shielding allowed on fuel line.


(g) Cooling

(1) One electric fan may be used.

(2) Radiator ducting must seal to nose.


9. Exhaust System:

(a) The headers, exhaust system, muffler must remain stock.

(b) The exhaust components may not be altered in any way.

(c) No header wrap allowed on exhaust or headers.

(d) Exhaust system may be painted with high heat paint.

(e) Exhaust system cannot be ceramic coated.

(f) No grinding on headers or header flanges.


10. Front Suspension:

(a) All front suspension parts must remain stock, size, weight as delivered by series supplier.

(b) No altering suspension parts.

(c) Upper and lower ball joints must be stock.

(d) Low friction ball joints are not allowed.

(e) Lower A-arms must remain stock.

(f)  Upper A-arms must remain stock.

(g) Left front upper a-arm must be 9.5”.

(h) Right front upper a-arm must be 9”.

(i)  No slotted cross shafts allowed.

(j)  No bearing cross shaft allowed.

(k) Spindles must be stock.

(l)  Front hubs cannot be lightened or modified.

(m) Strut tubes must be aluminum hex only.

(n) Tie rod tubes must be aluminum hex only.

(o) Steering box must be a GM Saginaw 12 to 1 ratio only.

(p) All rod ends must be magnetic steel.


11. Fuel and Fuel Cell:

(a) Standard gas station Pump gas only.

(b) No mixing fuel or fuel additives allowed.

(c) Fuel cell must remain securely mounted in stock location.

(d) Fuel cell must be vented to rear bumper cover.

(e) Fuel cell must have a ground strap from fuel cell ring to the chassis.

(f)  No cooling fuel at any time.

(g) Fuel line must be steel braided hose.


12. Hardware:

(a) All nuts and bolts must be solid magnetic steel only.


13. No Push Rule:

(a) Cars must be driven to tech and from tech to staging area for qualifying.


14. Post Race Tech:

(a) Top three finishing cars must report directly to tech area.


15. Heights:

(a) All heights will be checked with driver in racecar.

(b) Nose Height: minimum 4.5”.

(c) Side Skirt Height: minimum 4.5”.

(d) Frame Height: minimum 4.5”.

(e) Rear Quarter Panel at Tail and Deck lid: maximum 36”.


16. Radios:

(a) Two way radios are required.

(b) Each team must monitor race control during practice, qualifying and race.

(c) Radio frequency must be registered with the series.


17. Rear End:

(a) Full floater rear end with minimum .188 axle tubes only.

(b) Ford 9” mini spool only.

(c) Rear gear ratio must be 4.56 only.

(d) No lightening or back cutting gears.

(e) No lightweight yokes allowed.

(f) Solid magnetic steel axles only. (minimum diameter 1.200”)

(g) No cambered rear end housing.


18. Rear Suspension:

(a) All suspension mounts and pick up points must remain stock.

(b) All trailing arm tubes must be aluminum hex tubing.

(c) All rod ends must be magnetic steel 3/4” diameter.

(d) No quick adjusters allowed on track bar or top link.

(e) Brackets on rear end housing may not be moved or slotted.



19. Rear Wing:

(a) The rear wing must be mounted in original location.

(b) Rear wing must be mounted with approved mounts.

(c) Rear wing must fit Sportsman wing SRL template.

(d) Nothing can be changed on the rear wing.

(e) Rear wing tether must be attached at all times with approved hardware.


20. Safety:

(a) Lap belts must be 3” wide latch and link style.

(b) Seat belts must be SFI rated and dated within two years.

(c) Window net must be SFI rated and dated within three years.

(d) A professional racing seat is required.

(e) Seat must be made out of aluminum.

(f)  Seat must attach to chassis at six points w/3/8” grade 8 hardware.

(g) Approved 5# fire suppression system mandatory.


21. Shocks:

(a) Shock numbers must remain stamped on shock.

(b) Must use the following approved shocks:

(1) SRL310-42173/5

(2) SRL 310-42174

(3) SRL310-42175

(4) SRL 310-42174/6

(c) Bump stops are not allowed.


22. Springs:

(a) Coil over springs must be 2.5” ID x 14” tall.

(b) No barrel springs.

(c) Minimum front spring rate 200#.

(d) Maximum rear spring rate 500#.

(e) Only one (1) spring per shock allowed.

(f)  Only one (1) spring rubber per spring allowed.



23. Sway Bar:

(a) One piece 1.25” sway bar only.

(b) Sway bar mounts must remain stock as produced by SRL supplier.

(c) No quick adjusters allowed.

(d) Sway bar must attach to right side lower shock mount only.

(e) Left side sway bar must run on slapper plate.

(f) All sway bar components must be magnetic steel.


24. Tires:

(a) Hoosier 970 Tire only.

(b) Each car with be allowed five (5) branded tires at their first race.

(c) At each race event they will alloted one (1) branded tire per race.

(d) No other tires will be allowed for competition.

(e) You may practice on any 970 tire.

(f) No chemically altered tires, tire must remain as manufactured No shaving or grinding of tires, No “siping” or grooving

25. Tread Width:

(a) Front 63” max from center of tire to center of tire at spindle height.

(b) Rear width must be 62.5” from center of tire to center of tire.

(c) No wheel spacers allowed.


26. Transmission:

(a) Must be magnetic steel.

(b) Must be 3 speed Saginaw.

(c) Stock OEM transmission with three forward and one reverse gear.

(d) Transmission cannot be lightened or altered.

(e) Transmission must weigh 75 pounds without shifter.

(e) No polishing or coating internal parts.


27. Weights:

(a) Minimum weight before event is 2750# with driver and safety gear.

(b) All added weight (lead only) must be in left side lead rail.(3” x 4” tube)


28. Wheelbase:

(a) Wheel base must be 108” +/- half inch.

(b) Wheelbase must be within 1⁄2” from side to side


29. Wheels:

(a) SRL S2 stamped 15” x 8” steel wheel only.

(b) All wheels must be 4” backspace only.

(c) Minimum wheel weight is 19#.

(d) Lug nuts must be 5/8”-11 threads with a 1” hex outer dimension.

(e) No gun drilled wheel studs.


30. Transponder:

SRL-approved timing and scoring transponder mounting brackets must be installed on the right side frame rail, 24 inches behind the rear axle, mounted vertically with the square tab on the bottom, not higher than the bottom of the container. The bracket must be fastened with 3/16 inch diameter small head pop rivets (from the outside) through the holes in the center of the bracket with 3/16 inch diameter rivet washers on the inside.


No equipment or racecar will be considered as having been approved by reason of having passed through inspection ‘unobserved’, regardless of an S-2 car passing prior inspections, compliance with all rules must be made at each post inspection. Official’s decision will be final.


The basis of this race series is that the race car, parts and all component remain unchanged.  If you are interested in working to make modifications to your race car to help the cars performance other than the minimal set up options you have, then this series is not meant for you.




SRL S2 manufacturer and supplier is: Race Car Factory.

855 Meridian St

Irwindale, CA 91010

Phone 626-256-3322

Fax 626-256-3399





Personal Safety



In all matters pertaining to safety, Car Owners, Drivers and Crewmembers must review and educate themselves in all safety standards. It is the responsibility of the Car Owners, Drivers and Crewmembers to install, wear and maintain all safety equipment as specified by manufacturer’s instructions. This includes, but is not limited to; helmets, fires suits, racing suits, gloves, shoes, flame-resistant underwear, head and neck restraint systems, driver’s racing seat and safety belts. Any Safety infraction will deem the car ineligible for competition until the infraction has been repaired or corrected and the car re- inspected.


      Seat Belts and Shoulder Harness

1.        Each car must be equipped with an SFI 16.1 or SFI 16.5 – approved 5-point or 6-point seat belt restraint system and display a valid SFI 16.1 OR SFI 16.5 label. Unapproved seat belt restraint systems or components will not be permitted.

2.        An SFI 16.5-approved shoulder harness may be two (2) inches wide as it passes over the approved head and neck restraint device.

3.        Approved seat belt restraint systems must have a latching mechanism attached to the lap belt or , if cam lock latching mechanism is used, it must be attached to, the lap belt, the shoulder harness or the anti-submarine belts. This latching mechanism must provide a common connection and release for the lap belt, shoulder harnesses and anti-submarine belt(s), and must be designed with a quick and easy one-handed, gloved release of all belts in all conditions. It must either have one (1) of two (2) approved release designs.


Cam Lock

4.       A center (crotch) belt must be securely mounted to the lower seat frame at the bottom and to the lap

seat belt on top.

5.       Where the belts pass through the seat edges, it must have a grommet installed, be rolled, and/or

padded to prevent cutting of the belt. All seat belts and shoulder harness must connect at the lap belt with an approved quick release buckle. Untagged, undated belts will be considered out of date. The label cannot be in the adjuster.

6.        Seat belts and shoulder harness systems must have a production date within three years of the event date.


      Driver Seat

All driver seats must be manufactured by a recognized manufacturer of seat and safety equipment, multi-layer aluminum seat and approved by SRL Officials. Seats must remain “as purchased and produced”, no holes or other modifications made for weight reduction. Homemade seats or sprint car type seats are not permitted.

1.  Seat construction must be solid aluminum sheet material from the seat bottom to above the driver shoulder area; must be fully padded, with padded pelvis, shoulder supports on both the left and right side.

2.  A head restraint system, manufactured by a recognized manufacturer of seat and safety equipment, is mandatory and subject to SRL Officials approval. Bolt on systems are approved for competition.

3.  Seats recommended being equipped with left and right leg extensions, fully padded, running from the edge of the seat to the entrance of the foot box area.


      Fire Control and Safety

1.        A fully charged five-pound on board fire system with a minimum of two nozzles is mandatory. Gauge must be easy to read. The bottle must be certified from the manufacture every three (3) years. This cylinder must contain a minimum of five (5) pounds of DuPont FE-36 or equivalent.

2.        Driver uniform must be a multi-layer, full-coverage, one-piece fire-retardant uniform specifically designed for racing; Nomex-type or equivalent fire resistant uniforms mandatory. Nomex gloves, socks and racing shoes are mandatory. Nomex fire resistant underwear is recommended. Uniforms must be kept clean and in good repair. Soiled, torn, worn, or poorly fitting uniforms will not be allowed.

3. Drivers must wear a full-face helmet carrying at least one of the following certifications: Snell SA 2005, Snell SA 2010, Snell SAH 2010, FIA 8860-2004, FIA 8860-2010, or SFI31.1/2005 label at all times on the race track. SFI or Snell approval sticker must be visible for SRL Officials inspection.

  1. “M” type not allowed.
  2. Eye protection is mandatory at all times.
  3. Any helmet with the inside identification labels defaced, obliterated or removed will not be approved.
  4. Helmets showing wear or abuse, such as chipping or cracking, will not be approved.
  5. Helmet chinstrap must be Nomex covered.


Head and Neck Restraint Devices/Systems

At all times during an Event (practice, qualifying and competition), drivers must connect their helmet to an approved head and neck restraint device/system which is SFI-approved and acceptable to the SRL. The device/system must meet the SFI 38.1 specification and must display a valid SFI 38.1 label.

The head and neck restraint device/system, when connected, must conform to the manufacturer’s mounting instructions, and it must be configured, maintained and used in accordance with the manufacturer’s instructions.



The following are SFI 38.1 Head and Neck Restraint Devices/Systems are acceptable to SRL, other head and neck restraint device/systems meeting SFI 38.1 specifications may also be used:


DEVICE                  MODEL                  OPTIONS

HANS Device             Professional Series      Fixed or Sliding Tethers

HANS Device             Extra/Economy Series      Fixed or Sliding Tethers

HANS Device            Sport Series            Fixed or Sliding Tethers


More Safety


  1. Recommended: All entrants should have in their garage or pit area as part of their equipment, at all times, a fully charged 10- or 13-pound dry chemical, Halon, or its equivalent, fire extinguisher.


Two-way radio communication between driver and crew is required whenever car is on the track. Spotter must be in designated area at all times while car is on track, and must monitor Race Control at 460.0625.


PLEASE READ: It is ultimately the obligation of each participant to insure that his conduct and equipment comply with all applicable rules as they may be amended from time to time. No expressed or implied warranty of safety shall result from publication of or compliance with these rules. These rules are intended as a guide for the conduct of the sport and are in no way a guarantee against injury or death to participants, spectators or others. The SRL and its officials reserve the right to refuse entry to any event under their jurisdiction.  3.1.13