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70’s Stock Class Rules 

Type of Cars: Any American-made sedan or station wagon 1979 and older. No trucks, vans, El Caminos, hearses, 4x4's, limos, Imperials or Imperial sub-frames.


A. Body


  2. If OEM body mounts are used, the portion of the OEM mount between the frame and body cannot be altered, including the metal cone inside of rubber mount.

  3. If you choose to replace OEM body mounts, the OEM mounts may only be substituted with an actual rubber hockey puck (no homemade plastic or metal spacers allowed). They must be positioned in the original location and with the same intent as the factory installs them, but bolts may travel through the top of floor.


  5. A washer, no larger than 4” x 4” x ¼” may be placed on the top (inside car where bolt sticks through floor) and bottom of body mount bolts inside of frame. No welding washers to car body or frame.

  6. Do not add or relocate any body mounts and/or bolts.

  7. Core support body mounts may be replaced with a maximum of 6” spacer using rubber hockey pucks or no larger than 2” x 2” x ¼” round or square tube. If using square or round tube it can NOT be welded to the frame and/or core support.

  8. Maximum space between the top of the frame and the bottom of the core support must NOT exceed 6” regardless of the core support mounting location.

  9. Core support bolts may be replaced with up to ¾” all thread through the core support and hood. A single tab may be welded to the top of the core support for the all thread to run through. No additional metal or welding may be used.

  10. All thread may NOT extend more than 1” above the nut used to bolt down the hood. If you use this option it will count for 2 of the 8 allowable hood locations.

  11. Hood must have at least a 10” x 10” hole near the center for fire personnel access. Hood/trunk cutout bolts may be used. You may have no more than 12 per hood/trunk that are no larger than 3/8” bolts. Bolts must only be placed around perimeter of hole.

  12. If you are using engine driver plastic fan or clutch type fan, hood must cover fan and extend 10” past fan blades.

  13. Hood may be secured in 8 spots (6 spots if using the ¾” core support bolts through the hood) with chain (3/8” max), wire, and/or bolted (max size 3/8”) through angle iron (max size 2” x 2” x 4” ¼”).

  14. Chain or wire may wrap around the bumpers.

  15. All hoods MUST open on stock hinges or be removed completely for inspection regardless of cutout size. Factory hood latches must be removed.

  16. EACH door and trunk lid/tailgate may be secured in a total of 8 places of your choice on each panel by welding metal plates (4” x 4” x ¼” max), chain, #9 wire, and/or banding.


  18. No inside seams may be welded.

  19. If trunk lid cannot be fully opened for inspection, 10” x 10” inspection hole MUST be cut in trunk lid.

  20. No body creasing or shaping. Leave the quarter panels alone!​

  21. Wedging and lowering of trunk area will not be allowed. You may "V" the center of the trunk lid for visual clearance. Do not abuse!

  22. Trunk lids may be cut or bent to tuck.

  23. Quarter panels and tail light panel must remain vertical.

  24. Fender well sheet metal may be cut or rolled for clearance purposes and may be bolted back together in 5 spots using 3/8” bolts on each opening.


B. Cage

  1. Cage bars must be sheet metal to sheet metal.

  2. Bars must be single bars, not stacked or doubled.

  3. All components of cage must be at least 4” from the center of the firewall and floor at any point, including transmission and driveshaft tunnels.

  4. Rear bar may not be any further back than where the kick panel meets the bench seat.

  5. You may have a 24” tank bracket. It must be 4” off of the package tray or sheet metal hump for wagons​.

  6. Front bar may not contour the body. It must run straight across.

  7. All cage bars may be no larger than 5” x 5” except side bars. Side bars may be C channel up to 8”.

  8. Side bars may not go past the firewall or past the center of the rear doors. Side bars may be inside of doors.

  9. All bars must be inside the driver’s compartment except the roll bar.

  10. Roll bar must come off your rear seat bar or door bars (max 5” x 5” or 8” C channel). Roll bar must go straight across.

  11. Roll bar may be bolted or welded to the rood only. Roll bars may not have any tip outs.

  12. Non-door post cars may weld 1 post to each side of the car, centered on the door seams, 4” x ½” max, with no more than 4” extending down the door or onto the roof.

  13. 2 windshield bars or chains may be attached from the roof to the cowl area on the front windshield area only to protect the driver. Maximum size 4” wide by ¼” thick bar or 3/8” chain. They may not extend more than 4” on roof and cowl. This may not be used as a strengthener or to keep a car from bending.

  14. No rear window bars allowed.


C. Frames

  1. No painting or undercoating of the frames inside or out.

  2. No grinding or buffing of frames.

  3. No frame shaping/manipulation is allowed.

  4. No welding of frame seams allowed.

  5. Notching and pre-bending will be allowed. Do not weld notches back together.

  6. Wedging and lowering of trunk area will not be allowed.

  7. Front frame may NOT be shortened past the front of the factory core support location and core support MUST be bolted in the factory location.

  8. Patching and rust repair to body and/or frame will be allowed only if cleared in advance.


D. Bumpers

  1. Front & Rear bumpers may be welded no more than 6" from the end of frame. You may collapse the factory to that make and model shocks in factory locations and weld them solid. You may also hard nose the bumper following the guidelines of no more than 6" of weld on the frame rail. If you choose to hard nose, you can use no more than one 4" x 6" x ¼” mounting bracket per frame rail. Whether you choose to weld factory hardware or hard nose, you may only weld your 6" on one side of the frame rail.​

  2. Maximum front bumper height is 22” from the bottom of the bumper skin to the ground.

  3. Minimum rear bumper height is 14” from the bottom of the bumper skin to the ground.

  4. 76 & older Cadillac front frames cannot be shortened past the front edge of the larger round hole inside the frame horn. This hole must remain visible for inspection. If not we will be measuring from the front of the engine cross member to the back of the bumper at mounting point. This measurement can be NO LESS than 17 ½” NO EXCEPTIONS!!!

  5. Loaded bumpers will be allowed. All work MUST be done on the inside of a factory bumper.


E. Drivetrain

  1. Engine and transmission swapping between manufacturers is allowed.

  2. Do not strengthen frames or crossmembers with mounts.

  3. Motor mounts/cradle may be bolted or welded to crossmember ONLY.

  4. One engine chain per side may be used. The chain may be

    • Bolted to a factory hole in the frame (bolt may NOT act as a pin through frame)

    • OR

    • Wrapped once around the frame only (not welded)

    • OR

    • One link on each side may be welded directly to engine cross member or k-frame only

  5. A factory transmission crossmember must be used but may be altered in center for transmission mounting purposes only (4” wide x 12” long x ¼” thick max).

  6. If the car is equipped with a floating crossmember and you use a different crossmember, the free floating crossmember mounts and/or legs MUST be 5” from the factory crossmember that you use.

  7. Aftermarket shifters, gas pedals, ignitions switches, drive shafts (slider), suspension shocks, transmission coolers, electric fans, lower engine cradles with or without full front plate, pulley protector, aftermarket ball joints, and throttle linkages are allowed.

  8. Lower engine cradle must NOT be used to strengthen the car in any way before, during, or after the event.

  9. Pulley protector may not be used in any way to strengthen the car and cannot be used as a motor mount or connected in anyway other than to the engine cradle.

  10. Distributor protectors and transmission braces are NOT allowed. Aftermarket transmission bellhousings and tail shaft housings are NOT allowed.

  11. Steering may be altered from the steering box to the steering wheel.

  12. Water only in cooling system. Please drain antifreeze prior to arrival at the track.

  13. No solid metal engine fans allowed.

  14. All cooling fans must be under hood.

  15. No external radiator guards/protectors. A piece of expanded metal or screen may be used between radiator and cooling fan under hood.

  16. Exhaust may exit under the car or straight up through the hood.

  17. Some type of air cleaner must be used.

  18. No open carbs will be allowed.


  20. Metal fuel cells or approved marine style metal tanks are required when mounted inside of car. No gas cans or plastic tanks.

  21. Two batteries per vehicle are allowed.

  22. Batteries must be mounted securely to the passenger side floorboard and covered with a rubber mat. We recommend metal frames bolted or welded to the floor or chains. Do not use zip screw or rubber straps.

F. Suspension

  1. Cars may use any rear-end provided it is from a car (5 lug or less).

  2. Aftermarket axle shafts are permitted.

  3. No added braces or axle-savers allowed on rear-end housings.

  4. Any remnants of prior rear end braces must be COMPLETELY removed.

  5. Front suspension may be raised or locked by using torsion adjustments, spring spaces, a metal rod (1” diameter max) from the top of LOWER control are to BOTTOM of vehicle’s frame (no chains) OR front shocks may be replaced with 1” threaded rod in the stock shock location no combinations allowed. If you use the 1” thread option nothing can be welded this includes washers and/or nuts. If rod options is used, rod may not overlap side of frame.

  6. Front control arms and spindles may be interchanged between manufacturers provided no extra metal or welding is added to frame of vehicle.

  7. If you use an aftermarket ball join the collar you weld in or bolt in can only be ½” bigger than the ball joint without reinforcing the a-arm.

  8. Rear suspension may be locked or chained. One loop of chain (3/8” max) per side in rear is allowed. Chain must extend straight up and down from rear-end housing to package tray area OR around frame rail. Chain may not be welded to frame.

  9. Factory leafed vehicles must have factory spring packs with correct step-downs (minimum 2” step). No more than 2 replacement clamps will be allowed on each spring pack. They may not exceed ¼” x 2” x 5”.

  10. Factory OEM trailing arms may be shortened or lengthened (using same thickness material) to accommodate pinion angle with a maximum of 2” overlap, no additional material may be added. This includes Watts link style cars.

  11. ZTR brackets may be used. Upper mounting brackets must be bolted ONLY to the package tray. Lowers can be bolted OR welded on the side of frame. ZTR brackets cannot be mounted inside, on top or on the bottom of the frame and can be no larger than 9” x 8” x ¼” and cannot be used to stiffen any other part of the frame.

  12. If using the ZTR style brackets you MUST use factory OEM trailing arms (upper and lower) which may be shortened or lengthened (using same thickness material) with a maximum of 2” overlap. No additional material may be added.

  13. Rear shocks may be clamped or may be sleeved with pipe, but pipe may not be welded to frame of vehicle.

  14. OEM shocks may be replaced with aftermarket shock replacements up to 1.5” x 1.5” max square or 1.5” round. All shocks must be mounted in OEM locations.



G. Tires

  1. Valve stem protectors are allowed.

  2. You may use bead locks.

  3. You may use weld in wheel centers.

  4. No studded tires.

  5. No wheel weights.

  6. No foam filled tires allowed for safety reasons.

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