V-8 Thunder Stock Division

. Posted in Official Bubba Raceway Park Rulebook


  1. Any 1970 or newer American made production 2 or 4 door sedan. The minimum wheelbase allowed is 101” (1” tolerance) (centerline of front wheels to centerline of rear wheels). (This cannot be altered). Weight 3100 lbs. with original driver after completion of the race.
  2. No subcompact cars. No foreign convertibles, four wheel drive or front wheel drive cars allowed.  No chopping, shortening, or channeling. Both sides must be the same. In case a frame issue comes up from a wreck, get with tech to see how or if the chassis is capable to be put back to be legal.


  1. Completely stock for year, make and model. 
  2. Doors may be replaced with 18 gauge (.047”) steel. 
  3. Stock body panels or self-made body panels, aluminum or steel only, that is as close to stock appearing as possible. 
  4. Car body must be strictly stock.  No modifications or alterations of any kind unless outlined below.  No flaring of bodies. 
  5. Removal of interior parts which can be removed with hand tools are okay. No cutting of any panels allowed. Any interior part that is flammable must be removed.  Left and right passenger doors may be gutted for roll bars. Minimum of 4 bars on driver’s side. Three bars on passenger side.  All exterior trim must be removed. Removal and gutting of roof to install roll cage ok.
  6. Hood must have hood pins in front, hinges or pins at rear.  Hood must close in original stock position. No fiberglass or aluminum after-market or made hoods. 
  7. Inner front fender panels may be removed.
  8. Complete stock floor pan must be retained.  No sheet metal floor pan.  In case of repairing damaged, rusting or rotted floor pan you must use same gauge or heavier of stock floor pan. 
  9. Fenders may be trimmed for tire clearance. 
  10. Stock factory brake pedal must be mounted in original factory stock location. 
  11. The window channel on the front doors of a sedan style body may be removed.  All other window posts must remain as placed by manufacturer in original location.  All glass and plastic must be removed. 
  12. Plastic stock appearing noses only. No slope or late model style noses. 
  13. No side windows of any kind with the exception of factory quarter panel windows may be used.
  14. Factory spoilers and side skirts are okay.  6” by 60” maximum after-market spoiler. No side spoilers. Aftermarket side skirts must meet ride height rule.
  15. Bumpers may be steel tubing with no sharp edges, corners, must be rounded. Pipe may not be larger than 1 ¾” by .095 thickness.
  16. Steel tubing may be used to brace or protect radiator. One hoop bar over radiator attached to frame horns may be used. It may be braced with bars angled to frame horns.
  17. Wire Screen minimum 1” by 1” with three ½” bars must be installed in front of driver in place of windshield. Screen replaced entire original windshield.
  18. Inner skin of hood and trunk lid may be gutted.  Floor of trunk areal may be removed from centerline of rear end back.
  19. May have rub rails (one per side only) made of 1” round or squire tubing, ends must be capped at a 45 degree angle.
  20. Trunk and fuel cell area must be tightly sealed from the driver compartment.
  21. No decking allowed.
  22. Rear spoiler, from deck height to top of spoiler must not exceed 6” at any angle.
  23. Window net must unhook from the top.
  24. Battery must be self-contained and securely mounted in battery tray.
  25. No radios or audible communication devices except raceceiver.
  26. Dashboards are required and may be made of steel or aluminum.
  27. All pedals must remain in stock location, with the exceptions of clutch pedal and slave cylinder on cars converted to standard transmission that had no manual clutch.
  28. Stock OEM body parts are allowed.  May be stock replacement aftermarket. Stock body panels or self-made body panels aluminum or steel only that are as close to stock appearing as possible with no sharp edges or protrusions.
  29. Stock steel roofs are required. No aluminum roofs.  All sheet metal, roof height, firewalls, floor pans, and body mounts must remain in stock location and dimensions.

      Chassis and Suspension

All chassis and suspension components must be stock and mounted in stock location unless herein outlined.

  1. Aftermarket stock mount springs and spring perches are allowed.
  2. No composite leaf springs. Rear springs must fit in stock location and buckets. Rear coil spring bucket spacers okay. Leaf springs may run longer shackles than stock to compensate for bent frame rails, and can be run in any hole on either side.
  3. Lowering blocks are allowed up to two inch max and can interchange from side to side.  Ride height 6”.
  4. One shock per wheel.  Shocks must be in factory stock location only.  No coil over.
  5. May use threaded or non-threaded spring buckets on front only.  Buckets do not have to be same height, but must be welded.
  6. Camber may be adjusted with any length bolts.
  7. Sway bar may be removed. If the sway bar remains on car it must be stock for make and model.
  8. Stock replacement shocks: Steel body, non-adjustable.  Shock must be in factory stock locations.  50/50 or split valve shocks ok.  No external adjustable shocks. Extensions allowed.
  9. Shock claimer rule: $75 per shock and must forfeit own shocks.  Driver claiming shock(s) must have finished in top five (5) and be on the lead lap.  Claim and money must be presented to tech official within ten (10) minutes of race completion.  Claimee must also bring car straight to tech after completion of race for exchange of shocks.
  10. Steering components must be stock for make, year, and model of car.  Quick release allowed.  Quick steer okay.  Aftermarket power steering pump allowed. Quickeners are allowed with a 25lb weight penalty placed in front of the flywheel.
  11. Factory replacement offset upper control arm shaft okay.


  1. Stock for make and model. GM350, Chrysler360, Ford351 MAX.  Metric cars will be allowed 350 cubic inches.  Engine location in stock position for make and model in factory mounts.  Engines must remain strictly stock as produced by manufacturer. No modifications of any kind unless outlined herein.
  2. Eagle Rods part # 5700 BPLW non bushed or bushed.
  3. Scat Rods part # 3ICR5700 bushed or non bushed.
  4. Eagle Crank part # 103503480 two piece or one piece.
  5. Scat crank shaft part # 9-10442 two piece or # 9-10526 one piece.
  6. No high performance engine of any kind.  No high performance parts of any kind.  No air boxes.
  7. Heads 70cc minimum. 56cc head is acceptable for Ford Engine only with a 50 pound weight penalty.
  8. Three angle valve job is okay. Final cut no greater than 75 degrees. Must use stock valve size for cylinder head used.  No 2.02 head. Maximum valve size 194/150.
  9. Bronze guides okay.
  10. 1.270” O.D. maximum valve spring diameter. OEM replacement valve spring retainers are okay. No light weight, aluminum, or titanium.
  11. Stainless OEM stock replacement valves. Neck downs and swirl polished are okay.
  12. Screw in studs, guide plates, and poly locks are okay.
  13. No grinding on any engine part or component.
  14. Maximum overbore allowed is .060 + .010 for clearance.
  15. Optional: pulleys, oil pan and engine fasteners.
  16. Aftermarket or racing valve covers and oil pans are permitted.
  17. Aftermarket pulleys permitted. No fluid dampeners.
  18. Aluminum radiator and water pumps are okay.
  19. Cam lift: GM .390/.410, Ford .425/.450, Dodge .390/.420, Pontiac .388/.424. Camshaft may be degreed. No gear drives.
  20. Factory OEM stock 2 or 4 Barrel Quadrajet (choke plate and shaft may be removed) or Holley 4412 500 cfm with Mr Gasket PT#1929 adapter.  May remove choke plate and shaft, change jets, power valve and accelerator pump. Ford my use Mr Gasket 1933, which is a 2 barrel to 4 barrel adapter.  Ford may use Holley 1850. May remove choke plate and shaft, change jets, power valve and accelerator pump. No secondary metering block.
  21. Lifter Valley baffle and screens are okay.
  22. OEM four eyebrow flat top pistons are okay.
  23. Stock type replacement with stock type configuration, (L2256) forged pistons ok.
  24. Pistons assembly, including piston, rod, bolt and wrist pin, must weigh 1194 grams dry.
  25. Any air cleaner, steel top.
  26. Aftermarket power steering pump and engine cooler are okay. 
  27. All internal components cannot exceed factory OEM specs. It is your responsibility to provide factory data to back up your specs and not the tracks.
  28. Stock configuration style solid motor mounts allowed and must be mounted in stock location.  May chain, strap, or use OEM replacement urethane motor mounts. Examples of what is ok, but not limited to are Moroso Kit #62610 and #62630. For any other mounts please check with tech official before installation.
  29. Cast iron intake only. No marine or bowtie intakes.
  30. Z/28 flywheel is okay. Minimum weight is 14 lbs.
  31. All engine fasteners and bolts are builder’s choice.
  32. Crankshaft OEM stock may use cast or forged. May balance on bottom of counter weights only.  No grinding on any part of crankshaft.
  33. Rocker arms 1.5 ratio stamped steel only. No other ratio, no roller tip, no roller.
  34. Connecting rods stock OEM.     

      Drive Train

  1. Rear end must be strictly stock for make and model. Welded rear end is okay. Mini spool is okay. 
  2. C-clip eliminator kit is allowed. No lockers.
  3. May use aftermarket OEM replacement axles.
  4. Can run disc brakes.  Rotor must be solid. No aluminum hats.  Brake pads must remain stock. (No Racing pads)
  5. Engine location in stock position for make and model in factory mounts.
  6. Solid hub clutch discs are okay. Must be full circle.
  7. No lightweight clutch assemblies.
  8. No light weight clutch covers.
  9. Cars that did not come with a standard transmission can use a hydraulic clutch pedal only.     


  1. 12 volt battery fired ignition only.
  2. OEM points or HEI distributor only.
  3. May use billet distributor housing.
  4. Distributor may be locked.
  5. No printed circuit board modules.
  6. Alternator is okay.


  1. Stock OEM cast iron manifold or under chassis header with 3 inch collector.  $200 max on header. Must show receipt or part number for header.  Exhaust pipe must exit even with or behind the driver and no larger than 2 ½” all the way.
  2. No step headers.
  3. Mufflers are okay.


  1. No additives allowed.
  2. Pump or racing fuel is allowed.
  3. Maximum of 22 gallon fuel cell.
  4. Cutting the trunk for the fuel cell is permitted.
  5. No electric fuel pumps.
  6. Fuel cell must be in 12 gauge can and centered.
  7. Must be securely mounted with at least two 2” by 1/8” steel straps. 


  1. Stock factory OEM 4 wheel working brakes only (calipers must be the same size).
  2. No brake bias devices of any kind.
  3. May remove OEM proportioning valve.
  4. No aftermarket brake pedals.
  5. Brakes must retain OEM stock master cylinder and stock pedal assembly.

      Wheels and Tires

  1. Tires must be passenger car DOT 70 or 75 series radials only. No LT, no SUV, off road or purpose built snow tires or any tire with mountain and snowflake symbol. No recaps. All tires must be same size except for right front which is mandatory 8" Hoosier or RC4.
  2. 3 steel wheels 15x7 or 15x8  -- offset 3 or 4 inches but all must be same except rf.
  3. No wheel spacers.
  4. Right front tire will be either 8" Hoosier with 8" wheel or 10" wheel with Hoosier RC4 tire(sportsman). This is mandatory.
  5. 2” maximum offset on RF only.
  6. Beadlock ok on right rear only.
  7. NO tire softeners. NO soaking of tires. NO pre-heating of tires. NO chemicals of any type inside of tires except oxygen or nitrogen.  All tires are subject to a punch rule.


The Bubba Raceway Park officials may inspect any car and equipment at anytime for compliance.  All cars must have a safety inspection each season before they race.

  1. All required safety equipment and apparel must be in use while the car is on the track.
  2. Racing helmet with min Snell 95 rating. Neck brace or hans device recommended.
  3. Fire suit with SFI min rating of "I". No holes or torn fire suits allowed.
  4. Fire resistant gloves, shoes and socks must be worn at all times car is on track.
  5. A MINIMUM 4 point roll cage must be steel pipe or tubing, a minimum of 1 1/2" (1.50") outside diameter with minimum .095" wall thickness.  No square tubing or galvanized pipe allowed. No exceptions. Roll bar padding required around driver.  Unibody cars may be tied together not to exceed 10" overlap at joint front and rear.  No double frame.  All rear & front roll cage tubes must sit on original frame.
  6. An engine kill switch must be mounted in the window net area and easily accessible by the driver and from the outside of the car.  The switch must be clearly marked "Ignition switch" and show on and off position. 
  7. All cars must have a fire extinguisher minimum 2 lbs. securely mounted within easy reach of the driver. 
  8. A single quick release 4 point harness (minimum 3" belts) dated within the last 5 years or newer is required in all vehicles. All required belts must be in use anytime the car is on the track.  Racing harness must be attached to the role cage.
  9. Window nets are required on the driver’s side of the car and must be securely mounted.  Nets must latch at the top and be operational from inside and outside of car.  Drivers must be able to exit both sides of the car.
  10. Aluminum racing seats mandatory.
  11. Drive shaft must be painted white and include the car number. Drive shaft hoop will be a 5" diameter steel loop.  1" wide and 1/4" thick. It must be securely mounted to the frame 12" from the front universal. Must have one on rear drive shaft.
  12. One 12v battery shall be secured to frame of car and must be encased.
  13. All lead ballast must be painted white with car number and secured with one 1/2" bolt per 50lbs.  It is your responsibility to make sure your ballast stays in your car for everyone’s safety. Penalty weights must be painted red or orange.
  14. Throttle toe strap is mandatory.  Throttle linkage must have two return springs.
  15. All cars must have front and rear hook ups for towing.
  16. All cars must have a radiator over flow can. Water only for coolant.
  17. All standard transmissions must have a scatter shield.

If it's not stated in the rules it doesn't mean it's approved.  Please consult with the tech-man for approval.  All tech decisions are final.  The track reserves the right to add weight to any driver in the fairness of competition.