Afton Motorsports Park Street Stock Class Rules
The Street Stock class rules for Afton Motorsports Park are listed on this and four other pages, linked to below.
Page 1 of Rules: [Go to page 1] Includes Eligibility Requirements, Former Prostock/Super Stocks, Bodies and Aluminum Body Rules.
Page 2 of Rules: [Go to page 2] Includes Seats/Interiors, Roll Cage and Suspension.
Page 3 of Rules: [Drivetrain] [Weight] [Wheels and Tires] [Brakes] [Shocks] [Transmission] [Engine]
Page 4 of Rules: [Go to page 4] (Engine continued) Includes Vortec Head and Intake Heads, Headers, Intake, Ignition, Cooling System, Fuel Systems, Carburetor, Option 602 Street Stock Engine
Page 5 of Rules: [Go to page 5] Includes Body Installation Guidelines Diagram.
[PDF of Street Stock Rules] [Download Adobe Acrobat]
- Stock type rear ends only. May be from different size car.
- Ford 9' floater rears allowed. Components must be steel. (Internal and external)
- No wide 5 bolt patterns allowed.
- Rear lower control arm bracket center hole may not exceed 31/2" from bottom of axle tube.
- Welded or locked rears allowed.
- Spools allowed, no aluminum parts permitted.
- Racing axles allowed but no ratchet type differentials, Gold Trac, or any other aftermarket traction control devices allowed.
- Rear control arms may be aftermarket or fabricated. Lower rear must maintain OEM length, and mount in OEM locations.
- NO slotted holes in either rearend or on frame.
- Upper control arms may be adjustable and may use bushings or rod ends.
- Lower control arms may not be adjustable and must utilize stock style bushings.
- Drive shafts will be painted white and have a minimum of two steel safety hoops near front and rear.
- No chains, bungee cords or tin strapping.
- No aluminum drive shafts or half shafts allowed. Minimum 2 inch diameter steel driveshaft.
- All bolt on lead or added weights must be securely mounted, brightly painted, and have car number on it.
- All cars must weigh a minimum of 3000 lbs after racing with driver, no allowances made for water or fuel.
- ROC SERIES/SPECIALEVENTS: JACKING BOLTS WILL BE PERMITTED FOR SPECIAL EVENTS ONLY. THOSE CARS MUST WEIGH A MINIMUM OF 3,250 LBS.
- 8' steel wheels, may be any offset.
- Aftermarket steel rims highly recommended.
- Bead locks allowed on 4 wheels.
- No wide 5, aluminum or magnesium wheels.
- American Racer 70/245 non DOT racing tire is the track tire.
- No tire softeners or treatments allowed.
- Grooving or siping is allowed.
- Minimum of 5 lug nuts per wheel at all times.
- 1" steel lug nuts mandatory on all four corners with at least 1/2" studs, 5/8 recommended.
- ROC SERIES/SPECIALEVENTS: Both rear tires must be the track tire used by the hosting track. Fronts are not mandated and open to driver's choice.
- Must have operable and effective 4 wheel brakes.
- Dual master cylinder allowed.
- Front to rear brake bias adjuster allowed.
- Balance bars are allowed with external or remote adjusters.
- Right front brake shut off valve allowed may be within reach of driver.
- All right front brake components must be in place.
- Rear stock disc brakes allowed, but must be OEM type systems.
- No aluminum rotors or dual piston calipers.
- No electric brake shut-off.
- Steel bodied shocks only, must be Non-adjustable, one per corner.
- Steel bodied after market shocks with welded heim joint ends are allowed. Upper and lower mounts may be fabricated. Must be non-adjustable. (Example:No multiple holes)
- Stock automatic or stock manual transmissions only, with all gears working, including reverse.
- Automatic transmissions must have functional 11" torque convertor with no internal modifications allowed.
- No hollow converters allowed or any method of creating direct drive systems.
- Manual transmissions must be OEM production type transmissions. Three or four speed transmissions only.
- All forward and reverse gears must be in working order.
- Manual transmission must be operated by manual shifter within reach of driver.
- Clutch must be single disk, OEM style, minimum 10 ½ inch diameter. No metallic clutch disks allowed.
- Hydraulic release bearing allowed.
- Flywheel, pressure plate, clutch disc, and hardware must weigh a minimum of 35lbs.
- Manual transmission must have full steel 360 degree bell housing.
Optional Transmission, Clutch and Weight Rules:
A) Legal open motor with automatic or standard transmission by above rules: 2900 lbs.
B) Legal open motor with aftermarket transmission (Bert, Falcon, Brinn) or modified power glide (no converter) or racing clutch (small diameter/light weight): 3100 lbs.
C) Crate motor with open transmission (Bert, Falcon, Brinn) and Four Barrel Carb. (650 cfm): 3125 lbs.
Note: All standard transmission with clutch and flywheel must be equipped with a 360 degree steel bell housing. Aftermarket transmission cars (Bert, Falcon, Brinn) can use aluminum 360 degree bell housing.
Bert: P/N BERLMZ
Falcon: P/N 60100
Brinn: P/N 70001
I-88 reserves the right to adjust these weight rules at any time if deemed necessary for the purpose of fair competition for the class.
- Non-Performance World Product Replacement Chevy Heads allowed. Part numbers World 043600 or World 043610.
- Bow Tie Allowed
- No hand grinding, sanding, blending, or de-burring where a cutter or stone leaves off.
- Sand blasting, bead blasting, add dipping, porting, polishing, and welding are prohibited.
- No titanium valve train parts allowed. All Rockers 1.5 - 1.6
- Screw in studs and guide plates.
- No relieving or unshrounding of valves in combustion chamber.
- May run double valve springs.
- All factory casting numbers must remain visible.
- No aluminum heads, even If they were OEM parts.
- Maximum cubic inch 360. Maximum displacement:
- GM: 350ci+.060", 4" bore x 3.480" stroke
- Ford: 351ci+.060", 4" bore x 3.5" stroke
- Ford: 347ci+.060", 4" bore x 3.4" stroke
- Chrysler: 360ci+ .060", 4" bore x 3.578" stroke
- Chrysler: 340ci+.060", 4.040" bore x 3.13" stroke
- Blocks may be decked, but piston must not extend above deck at all.
- Wet sump oil pans only.
- Flat tappet cams only.