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Thunder Bomber 2018
Thunder Bomber 2018
GENERAL - Tech man has right to check this every week.
1. No nitrous or traction control.
2. After 3 times of refusing to tear down - you will be disqualified from competing
in this division the remainder of the year.
3. A driver cannot compete in this division and a different division on the same
night. (Will be at the Track Promoters Discretion)
4. Cars must be neat in appearance.
5. Cars must weigh 3300 pounds with driver after race.
6. 8" wheels max .25" tolerance - 14 or 15" - must be same size all the way
around. (no Aluminum wheels)
7. No dot racing tires.
8. Any 70, 75, or 78 series street legal dot tires series radials – no directional or
9. 8" towel city racing recap ok but must punch 50.
10. May run beadlocks but must face outside.
11. May run offset rims and wheel spacers.
12. Stock brakes and master cylinders.
13. OEM brake calipers only - no aluminum.
14. Duel master cylinder ok - adjusters ok.
15. Headers are legal but must exit parallel to ground. NO TRI-WYE
HEADERS, NO H-PIPES, AND NO X-PIPES (Not turn down on pipes)
16. Aluminum radiator with made brackets ok.
17. no electric fan.
18. Fuel cell must be mounted inside of trunk with firewall between driver and
fuel cell. Must run pump gas and/or track fuel
19. Seat must be securely fastened to frame and or roll cage.
20. Cars must have number on sides and top and able to be read by score tower.
21. Stock unless otherwise stated.
BODY - Visual protest only.
1. No late model noses or fender flares.
2. Stock unless otherwise stated.
3. 1968 or newer American made car.
4. No station wagons, trucks, jeeps, convertibles, mustangs, or pony cars. No strut
5. Rear of car must be closed - no holes or flaps.
6. Must have a deck lid.
7. May make front fenders, doors, and rear fenders.
8. No side spoilers. No plastic side skirts.
9. Spoiler may not exceed 60" wide by 6" tall and no spill plates. (no straps or
spoiler supports of any kind)
10. Cannot exceed 48" from ground to the top of the rear spoiler.
11. May run any replacement roof - must be 48" X 50" – Don't do anything crazy.
12. Aluminum door and fenders ok.
13. 13" minimum door and rear glass opening.
14. Interior can be boxed in.
15. Front and rear bumpers - rubber nose ok - stock appearing - no cow scoop.
16. Breather must be boxed in on all 4 corners and cannot exceed 2".
17. May NOT pull air from inside car.
18. Front inside wheel wells can be cut or removed for clearance but not
19. All firewall holes must be covered.
20. Must have stock firewall in original location. Firewall must extend to doors.
21. May replace dash with sheet metal - interior metal cannot be higher than
22. Gutting hood and trunk ok.
23. Bumper cannot exceed past the inside of the rear tire or must run a bumper
24. May use Lexan in rear side windows.
WHEEL BASE / FRAME
1. Frame must match make and model of car - 1" tolerance +/- allowed.
2. No shortening of frame - must be stock - no x-ing or cutting of frame.
3. Length between spring eyes must be stock.
4. Wheel base for make and model.
5. Engine must be in stock location.
6. Radiator must be in stock location
ENGINE - BOTTOM END
1. Any OEM stock size engine - max size 363 - .060 over bore max.
2. Engine must be in original location - aftermarket mounts ok.
3. Repaired engine parts must be approved.
4. ARP Rod bolts ok but must remain stock size - 3/8.
5. 1 piece rear seal block ok.
6. No high performance engines or special order parts.
7. .060 over bore max.
8. Stock blocks only.
9. Must be stock replacement low compression piston. Cannot cut top of piston.
10. No flat top 4 eyebrow piston - must be dished.
11. Speedpro H423 NCP replacement piston ok. No metric ring package.
12. Pistons must be at least .009" in block.
13. No bottoming of lifters.
14. Stock crankshaft.
15. No knife edging or lightening, etc.
16. Cast crank must weigh 48 lbs.
17. No stroking or destroking.
18. Journals may be turned no more than .060".
19. Rod width may not be less than .940. No powder coated rods.
20. Stock timing chain gear set or Cloyes C-3023X adjustable timing chain. No
offset key ways.
21. Balancer 6 3/4 by 1" no machining.
22. May run racing pulleys - no serpentine pulleys.
23. Aluminum water pump allowed.
24. No serpentine pulleys - v belt racing pulleys ok.
25. After market fuel pump ok.
26. After market power steering ok.
27. 2 piece timing covers ok.
28. No remote oil filter or evac system
1. Any open chamber head ok but must meet the following criteria. No
2. May run stock replacement screw in studs or pin them.
3. May run aftermarket valve cover.
4. Heads cannot be less than 72 cc.
5. No angle milling.
6. Stock or stock replacement valve for make and model.
7. Valve springs can be z28 springs.
8. No cutting under 45 - no competition valve job - no 3 angle valve job.
9. Shims can be used under valve springs with a limit of .60 per string.
10. May use off set locks but not with shims.
11. Rocker arms must be stock or stock replacement. 1.5 max. No self aligning
12. No porting or polishing.
13. Steel valves only.
14. Stock stem diameter.
15. No Vortec parts.
1. Stock cast iron.
2. No Holley pattern factory intakes.
3. No aluminum intakes.
4. Must have vacuum fitting behind carb.
1. Stock 2 or 4 barrel only.
2. No modifications except choke flap removal.
3. No removal of choke horn.
4. 600 Holley part # 1850 ok - must be box stock with Mr. Gasket adaptor part
#1932 May use (2) .070 gaskets max.
1. Stock timing chain or Cloyes C-3023X adjustable timing chain.
2. .390 - .410 lift.
3. 112 lobe separation +/- 1 degree.
4. Advancing or retarding the cam in car with adjustable timing ok.
5. Cloyes C-3023X only - no cam buttons.
6. Stock cam or stock replacement cam only.
7. Duration for intake + 2 degrees / -10 degrees.
8. .006 - 256 degrees.
9. .050 - 195 degrees.
10. .200 - 95 degrees.
11. Duration for exhaust + 2 degrees / - 10 degrees.
12. .006 - 261 degrees.
13. .050 - 202 degrees.
14. .200 - 106 degrees.
15. Must have 18" vacuum at 1000 rpm.
16. Hydraulic cam and lifters only.
17. Cams CS-274 Sealed Power and CCS-2 Melling and Comp Cam 12-105-3
are a stock produced cam and will be looked at with a little more variance.
All custom ground cams will be required to meet the above specifications.
FLYWHEEL AND CLUTCH ASSEMBLY
1. Stock steel flywheel - 14 lbs. Minimum.
2. Stock type clutch and pressure plate - minimum 10.5" (Pressure plate 12lb
3. May use hydraulic clutch.
1. Must be stock with all working forward and reverse gears.
2. May run 350 or 400 turbo automatic with OEM working torque converter, stock
type and 11" minimum. May run transmission cooler.
3. No power glides.
4. Aftermarket throw out bearing ok.
5. No lightening of gears.
6. 3 speed straight drive cast iron transmission with all working gears.
7. Straight drive transmission cars must have blow proof bell housing or scatter
shield of 1/8 steel.
8. May use hydraulic clutch.
1. Has to be stock for model of car or may run 2" driveshaft.
2. No carbon fiber. No Aluminum
3. A "U" or square type safety loop on front of drive shaft assembly is required.
1. Stock type ignition.
2. Stock type distributor only. No Billet
3. No high performance distributors or high performance parts.
4. No altering firing order.
5. No msd's with boxes.
1. Gm 10 or 12 bolt rear-end.
2. 9" ford or floater ok. 9" Ford mounting points must be stock type with NO
adjustability. 4 1/2" max - 3 1/2" min from center of the axle tube to center
of trailing arm bolt. (ANY ADDITIONAL HOLES MUST BE REMOVED)
3. Shocks have to be in stock location - may move for travel only (max 3 in) No
4. May run aftermarket axels.
5. Any gear ratio allowed.
6. Locked or limited slip rear ends allowed.
7. Full spools ok. (no scalloped)
8. No gun drilled axels.
9. No gun drilled rotors or scalloped rotors.
10. No lightening of any parts.
11. All components must be made of steel.
12. Disc brakes ok - doesn't have to match model of car.
13. Can cut top of trailing arms for pinion angle.
1. Suspension must be stock.
2. May run racing springs with adjustable buckets.
3. Top a-frame can be cut or move top mounting perch.
4. No adjustable blocks - 4" of lowering blocks max.
5. Tube type a-arm on top only ok – nonadjustable - screw in ball joints on top
ok. ball joint must be mounted on top of a frame (no QA-1) no rebuildable
(1/4 inch tolerance)
6. Can use heavy duty OEM steering and suspension parts.
7. Leaf or coil springs can be changed to stronger leaf or coil of the same type.
8. Cutting of coil spring allowed - rear shims on coils are ok.
9. Adjustable or non-adjustable spring buckets ok.
10. Shocks must be in stock location - may move for travel only – no angle
11. Adjustable buckets in rear ok.
12. All hook up points on chassis must be in stock location.
13. Cannot change angle of rear shock.
14. Top trailing arm may be cut for pinion angle only.
15. Leaf spring cars may adjust perches for pinion angle.
16. May adjust rear shackles.
17. After market bushing in a-frames and trailing arms ok but may not swivel.
18. No heim joints on any shocks.
19. May run any stock body racing shock.
1. All lead must be secured with bolts and/or metal clamps. Duct tape or zip ties are not acceptable.
2. 25 lb. weight break for Hans, or containment seat or both. (25 lb max.)
3. Must have working fire extinguisher in car.
PROTEST AND CLAIM RULE
1. Protest bottom - $500
2. Protest any 3 items - $300
3. Cam protest - $300 - track keeps $100.
4. Acceptance fee - $100
5. Track keeps $100
6. Tech man has final say.
Posted by Wayne Clayton