CASPER SPEEDWAY ASSOCIATION
PO BOX 4353
CASPER WY 82604
www.CasperSpeedway.com * email: [email protected]
HOBBY STOCK RULES
The Casper Speedway Head Tech person has the final say in the interpretation of a rule. This say will be final. If
an item is not stated as allowed, it is deemed to be disallowed.
Rule 1- Car Type:
1. Any American made car (no trucks) with a factory wheel base of 108.
2. No Convertibles allowed.
3. No four wheel drive or front wheel drive cars allowed.
Rule 2- Bodies:
1. Must be steel and remain strictly stock.
2. Hoods may be trimmed and liner removed. No aftermarket.
3. No cutting or trimming of any body panel is allowed, except for bar and roll cage installation.
4. All glass and chrome must be removed. This includes any exterior chrome, moldings, emblems and door
handles, bumper guards and plastic grills. Fiberglass parts that may be subject to being broken must be
removed.
5. All flammable materials must be removed from inside the car.
6. Steering shaft must remain in stock location. A removable steering wheel is allowed and highly encourage. A
solid shaft must remain the same length as a stock shaft a collapsible shaft is recommended.
7. Bolt on accessories in the engine compartment may be removed. Bolt on accessories in the driver’s
compartment will be removed.
8. Full uncut floorboard must extend from the front firewall to the new bumper. Must remain uncut., but may
be remanufactured due to rust. Trunk may be cut for roll cage.
9. Inner front fender wells may be removed. Front and rear fenders may be trimmed for tire clearance. All
sharp edges must be rolled or covered.
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10. Doors may be welded or bolted shut. If bolted shut a minimum 1 1/2 strap with 2 bolts on each end must
be used.
11. Bumpers may be welded to help prevent loss. Each end must be turned in to prevent hooking another car.
Bumpers must have OEM mounts, no after-market or extra materials allowed.
12. One bar no longer than 2” O.K. for radiator protection is allowed. Bar must be horizontal to the frame and
behind the sheet metal. Two vertical bars will be allowed on each side of the radiator for support of this hoop,
but not to go through, must stay in front of firewall.
13. Bars for leg protection are allowed.
14. Uni-body cars must have a plate minimum 1/8” thick X 6” square welded under the main cage legs. Plate
may be securely welded to main structure of uni-body or be bolted through the structure with a matching
plate on the underside.
15. Uni-bodies tied together with 2 X 1 tubes.
16. No tinning in passenger compartment
17. Front Hoops are allowed but not mandatory May be connected to frame.
Rule 3 - Suspension
1. No modifying of suspension.
2. All suspension parts must remain absolutely stock for make, model and year of car. No spacers aftermarket
parts of any kind or hold down chains allowed.
3. Rubber suspension bushing only. No polyurethane, plastic, steel, aluminum, brass or any or the material not
OEM for the model used.
4. Stock OEM spring only. No air shocks or shocks with helper springs allowed. No aluminum suspension
components allowed.
Rule 4 -Transmission and Rear Ends
1. All drive train components shall be strictly unmodified stock OEM parts.
2. Stock passenger car type transmission for make and model of car.
3. Stock passenger car type rear end only.
4. Rear end and transmission must match family of car used. Ford for a Ford, Chevy for a Chevy.
5. All cars must have forward and reverse working gears.
6. Automatic and manual transmissions allowed.
7. Automatic transmissions will have a stock working 10” torque converter. An add-on oil cooler is allowed,
but must be shielded from the driver if located near the driver’s compartment. No material may be added to
torque converter to achieve and to equal 10” measurement. ALL converters shall contain 4 quarts of fluid.
Although a quick oil detection plug is not required at this time. Scatter shields optional but not required.
8. Stock clutches and fly wheels only must adhere to OEM specs no Aftermarket Clutches or fly wheels
9. Rear ends may have spider gears welded or posi-traction.
10. No aluminum components allowed.
11. Spools are allowed, but NO ALUMINUM.
12. Rear end gears may be run no deeper than 4.11 gearing.
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Rule 5- Engines
1. No high performance engines allowed.
2. All engine components must be strictly stock and stock OEM production availability for make and model of
car.
3. Engines may be interchanged within their family line only if no medications of any kind are required and all
mounting remains in stock placement.
4. Up to .60 over bore is allowed.
5. Pistons shall be a stock flat top or less. No dome pistons allowed. 9.5 to 1
6. No aluminum manifolds, stock or otherwise.
7. Stock exhaust manifolds only, no center dump Chevy allowed. Exhaust must extend past the driver and
remain under floor board.
8. ABSOLUTELY NO machining, milling, or modifying of cylinder heads, intake manifolds, exhaust manifolds,
carburetors of any portion of the cylinder block. NOTE: Minor milling of the head in the case of an engine
overheating problem which causes a slight warp will be allowed. Hobby Stock Rep must be told of the minor
milling before it takes place. The class rep will have the right to be present or to inspect the work done at
his/her discretion. No angle milling of heads allowed.
9. All engine and components except camshaft and lifters must remain and be OEM factory production
available for engine to be legal. 350 Chevy must run 350 crank and 350 rods.
10. All cars must have a hydraulic flat tappet cam with a .450 gross valve lift or less with the following
exception: Ford 429 intake and .486 exhaust gross valve lift and a Ford
460 which is a .437 intake and .481 exhaust gross valve lift. No roller cams, no roller lifters or no roller rockers
stock or otherwise. It will be the driver’s responsibility to prove the legality of his/her cam.
11. No electric fuel pumps, stock mechanical only.
12. Stock OEM ignition only.
13. No out of ordinary add on equipment allowed.
14. Carburetion will be limited to one (1) stock Holly 500 CEM 2-barrel, part number
4412, with a 1/11/16” throttle bore. No grinding or polishing of any kind allowed. All carburetor components
must be for a 500 Holley. no milling or grinding of throttle shaft allowed. Shaft must stay round. Choke can be
removed but not the air horn. Must have stock measurements. Maximum thickness of gaskets and adapter
plat will be 1 3/8”.
Stock aluminum adapters only. No high performance adapters allowed. Spacer opening must be perpendicular
to the bar of carburetor. No adjustable or slider adapters.
15. Stock two or four-barrel intake manifolds only.
16. Maximum of one fixed, no-adjustable space allowed on four-barrel intake. Maximum Thickness of 1 ¼”. No
Marine or van manifolds.
17. No heads allowed that are listed as high performance in the interchange manuals.
18. Chevy heads: NO casting numbers ending with 040, 041, 186, 291, 191, 370, 432,
461, 461 X 462. No bow tie, no SO, no w-2 heads. No 202 intake valves on Chevy or
Chrysler. No air flow devices allowed below carburetor.
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19. After market oil pan is acceptable, not required.
20. The engine must remain in its stock location. You may NOT relocate the motor mounts.
1. Machine work to allow Screw in Studs allowed.
22. Aluminum or aftermarket pulleys allowed.
RULE 6- SAFETY
1. Car must have a Six point roll cage.
2. Four bars required on driver’s side.
3. Three bar minimum on right side.
4. 1 ½” x .095 minimum mild steel tubing on main roll cage.
5. A competition safety harness with 3” belts mounted in five points required. Belts must meet the required
safe age limit for use. Belts must be fastened to a point on the frame or cage. These need to be replaced every
3 years.
6. Race type seats required. No fiberglass
7. Must have window net. Spring loaded only.
8. Must have a screen and/or bars in front of driver.
9. Roll bar padding will be used where the drivers head or arms make contact with the roll bars. This includes
halo and vertical cage bars.
10. Drive shafts shall be painted white.
11. Drive shaft must have a safety hoop 360 degree around.
12. A plate on drivers door required with 1/8 minimum thickness. Must cover from top to bottom bar.
RULE 7- FUEL
1. Pump gas only, 92 octane or less.
2. No additives, alcohol, or exotic octane boosters allowed.
3. Fuel may be tested at any time.
4. No adjustable fuel tanks allowed.
5. Racing fuel cell required. Fuel cell must be enclosed in approved metal or plastic box. Plastic fuel bladders
will not be allowed to be bolted down by themselves.
6. Protection bar around fuel cell required. Bar must protect rear side of tank from collision and extend below
the bottom level of the tank.
7. Fuel system must meet safety requirements at all times.
8. Fuel cell must be mounted above the factory trunk floor level. Trunk floor must be fully tinned in.
RULE 8 -WHEELS AND TIRES
1. Approved steel safety wheels or racing wheels only. No stock rims allowed.
2. Bead Locks not Allowed
3. No tire is to be ground on, cut on, or modified in any way at the track
4. No aggressive tread design is allowed. All season tread allowed. No mud or snow tires allowed.
5. Maximum tire size is p235/70 R15 or up to series tires in actual passenger car type tire.
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Any Hoosier tire allowed no modifying or grinding of tires allowed at the track
6. Maximum rim width 8 inches.
7. Wheel studs will be required to be ½” dia 1’’Lug Nuts. On All Wheels
8. No welding on rims.
RULE 9 -WEIGHT
1. 3500 lbs. Minimum, including the driver.
2. All weight, if added, must be mounted with a minimum of two ½” bolts. Weights must
be painted white with car number written on them.
3. Weight cannot be mounted in driver’s compartment.
4. No unshielded batteries in driver’s compartment.
RULE 10- TEARDOWNS/CLAIMING OF MOTORS.
TEARDOWNS:
1. Protest fees: $250.00 cash for either the top end or the bottom end. $500.00 cash for the whole motor. You
must write down what you want checked.
2. The only person that shall be present at a teardown shall be the following: the driver of
the car in question, the owner of the car in question, up to two pit crew persons of the car in question, the
protesting driver, the Hobby Stock Class Rep, the Casper Speedway official, the Casper Speedway Tech
Inspector, and any helper requested by the Casper speedway Tech inspector. Any other person not listed must
be authorized by the Casper Speedway Tech inspector. Any other driver not involved with the car or Casper
Speedway members will be fined a minimum of $50.00, if you show up at a tear down.
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