We will continue to run these 2 divisions together unless we a good car count in both divisions then we will
split them up...
2018 Thunder bombers rules....
Thunder Bomber 2018 (USRA rules)
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
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
7. No dot racing tires.
8. Any 70, 75, or 78 series street legal dot tires series radials – no
directional or competition tires.
9. 8" towel city racing recap ok but must punch 55.
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.
RULE CLARIFICATION ON EXHAUST (EFFECTIVE APRIL 14TH) - NO TRI-WYE HEADERS, NO H-PIPES,
AND NO X-PIPES
16. Aluminum radiator with made brackets ok.
17. Fuel cell must be mounted inside of trunk with firewall between
driver and fuel cell.
18. Seat must be securely fastened to frame and or roll cage.
19. Cars must have number on sides and top and able to be read by
20. 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
5. Rear of car must be closed - no holes or flaps.
6. Must have a deck lid.
7. May make front fenders and rear fenders.
8. No side spoilers.
9. Spoiler may not exceed 60" wide by 6" tall and no spill plates.
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
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
16. Breather must be boxed in on all 4 corners and cannot exceed 2".
17. May pull air from inside car but no forced air no forced air.
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.
21. May replace dash with sheet metal - interior metal cannot be higher
22. Gutting hood and trunk ok.
23. Bumper cannot exceed past the inside of the rear tire or must run a
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.
10. No flat top 4 eyebrow piston - must be dished.
11. Speedpro H423 NCP replacement piston ok.
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. No balancing.
19. Journals may be turned no more than .060".
20. Rod width may not be less than .940.
21. Stock timing chain gear set only no offset key ways.
22. Balancer 6 3/4 by 1" no machining.
23. Engine must be in original location but may run aftermarket mounts.
24. May run racing pulleys - no serpentine pulleys.
25. Aluminum water pump allowed.
26. No serpentine pulleys - v belt racing pulleys ok.
27. After market fuel pump ok.
28. After market power steering ok.
29. 2 piece timing covers ok.
1. Any open chamber head ok but must meet the following criteria.
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 size of 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.
12. No porting or polishing.
13. Steel valves only.
14. Stock stem diameter.
1. Stock cast iron.
2. No Holley pattern factory intakes.
3. No aluminum intakes.
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 only.
2. Or Cloyes C-3023X adjustable timing chain ok.
3. .390 - .410 lift.
4. 112 lobe separation +/- 1 degree.
5. Advancing or retarding the cam in car with adjustable timing ok.
6. Cloyes C-3023X only - no cam buttons.
7. Stock cam or stock replacement cam only.
8. Duration for intake + 2 degrees / -10 degrees.
9. .006 - 256 degrees.
10. .050 - 195 degrees.
11. .200 - 95 degrees.
12. Duration for exhaust + 2 degrees / - 10 degrees.
13. .006 - 261 degrees.
14. .050 - 202 degrees.
15. .200 - 106 degrees.
16. Must have 18" vacuum at 1000 rpm.
17. Hydraulic cam and lifters only.
18. 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
FLYWHEEL AND CLUTCH ASSEMBLY
1. Stock steel flywheel - 14 lbs. Minimum.
2. Stock type clutch and pressure plate - minimum 10.5".
3. May use hydraulic clutch.
1. Must be stock with all working forward and reverse gears.
2. Automatic transmission torque converter stock type and 11" minimum.
3. May run transmission cooler.
4. Aftermarket throw out bearing ok.
5. Automatic transmissions ok.
6. No lightening of gears.
7. 3 speed straight drive cast iron transmission with all working gears.
8. Straight drive transmission cars must have blow proof bell housing or
scatter shield of 1/8 steel.
9. May use hydraulic clutch.
1. Has to be stock for model of car or may run 2" driveshaft.
2. No carbon fiber.
3. A "U" or square type safety loop on front of drive shaft assembly is
1. Stock type ignition.
2. Stock type distributor only.
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.
3. Shocks must be in stock location - may move for travel only – cannot change angle.
4. May run aftermarket axels.
5. Any gear ratio allowed.
6. Locked or limited slip rear ends allowed.
7. Full spools ok.
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.
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
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, cannot change angle
11. Adjustable buckets in rear ok.
12. All hook up points on chassis must be in stock location.
13. Rear shock location must be stock on top and can be moved on
bottom for travel length only.
14. Cannot change angle of rear shock.
15. Top trailing arm may be cut for pinion angle only.
16. Leaf spring cars may adjust perches for pinion angle.
17. May adjust rear shackles.
18. After market bushing in a-frames and trailing arms ok but may not
19. No heim joints on any shocks.
20. May run any stock body racing shock.
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
-----------2018 Pure stock V8 rules------
GENERAL - tech man has right to check this every week
· No nitrous or traction control
· may run engine fan, no electric fan
· may run air breather, aftermarket ok. Cannot pertude though hood. No air box
· ford soleniod, radiater, and fan shroud can be made from aluminum
· all 14" or 15" rims
· no dot racing tires
· tires - any 70, 75, or 78 series street legal d.o.t. Tires - doesn't have to be same size
· no truck, mud grips, high performance, directional, special order, snow, trick gumball, fancy,
or exotic tires of any kind
· wheels must be stock steel or may run the aftermarket nomad spoke wheels (wagon style)
· 7" stock offset wheels only - no beadlocks
· large 1" wheelnuts are ok
· battery may be moved to inside drivers compartment and must be enclosed and securely
· rollcage required - must be 4 point with 3 drivers side bars and 2 right side bars minimum
· may run bars to radiator but may not pertrude through radiator support
· may run bars to back but no bumper bars pertruding outside
· fuel cell mandatory with 22 gallon max - hole in trunk may have 3" clearance cut around cell
· must have steel firewall where back seat was
· no lead or any weight may be added to car
· exhaust must be stock cast iron. No center dump manifolds. No x pipes or h pipes. Factory y
· aluminum radiator ok
· fuel cell must be mounted inside of trunk with firewall between driver and fuel cell
· cars must have number on sides and top and able to be read by score tower
· stock unless other wise stated
· stock brakes
BODY - visual protest only
· stock unless otherwise stated
· 1968 or newer American made car
· complete stock body must be retained. Can cut 2" below factory crease to replace body panels
· may use steel 2" below factory crease for quarter panels but must look stock and I do mean stock
20 gage steel
· may use steel doors but must look stock and I do mean stock 20 gage steel
· may run rubber nose - top part only
· no cutting, chopping, channeling, shortening
· hood hinges may be removed
· all chrome, plastic and glass must be removed
· steering column must remain stock but may use quick release steering wheel
· may use hood pins to hold hood down
· all firewall holes must be covered
· must have stock firewall in original location
· may replace dash with sheet metal
WHEEL BASE / FRAME
· stock only
ENGINE - BOTTOM END
· engine must be strickly stock for that make and model and in original mounts
· repaired engine parts must be approved
· 1 piece rear seal block ok
· no high performance engines or special order parts
· .060 over bore max.
· stock blocks only
· must be stock replacement low compression piston
· no flat top 4 eyebrow piston - must be dished
· speedpro H423 NCP replacement piston ok
· pistons must be at least .009" in block
· no bottoming of lifters
· stock crankshaft
· no knife edging or lightening, etc
· cast crank must weigh 48 lbs
· no stroking or destroking
· no balancing
· journals may be turned no more than .060"
· rod width may not be less than .940
· stock timing chain gear set only no offset key ways
· balancer 6 3/4 by 1" no machining
· heads for make and model
· heads cant vary more than 4 cc's from stock
· no angle milling
· stock size of valve for make and model
· valve springs can be z28 springs
· shims can be used under valve springs with a limit of .60 per string
· may use off set locks but not with shims
· rocker arms must be stock, no long slotted rockers
· no porting or polishing
· steel valves only
· stock stem diameter
· cannot run 993 or 441 heads
· no cutting under 45 - no competition valve job - no 3 angle valve job
· stock cast iron
· no holley pattern factory intakes
· aluminum intakes on factory original cars must remain unpainted
· Can block off exhaust gas crossover
· must be a stock 2 or 4 barrel only
· no modifications except choke flap removal
· no removal of choke horn
· No spacer of any kind 1/4 inch gasket only
· stock timing chain only
· or Cloyes C-3023X adjustable timing chain ok
· .390 - .410 lift
· 112 lobe seperation +/- 1 degree
· advancing or retarding the cam in car with adjustable timing ok
· Cloyes C-3023X only - no cam buttons
· stock cam or stock replacement cam only
· duration for intake + 2 degrees / -10 degrees
· .006 - 256 degrees
· .050 - 195 degrees
· .200 - 95 degrees
· duration for exhaust + 2 degrees / - 10 degrees
· .006 - 261 degrees
· .050 - 202 degrees
· .200 - 106 degrees
· must have 18" vacuum at 1000 rpm
· hydraulic cam and lifters only
· Cams CS-274 Sealed Power and CCS-2 Melling 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.
· automatic transmission torque converter stock type and 12" mininum
· may have a cooler mounted in the drivers compartment
· automatic transmission only - no power glide
· man run an aftermarket shifter
· has to be stock for model of car
· no carbon fiber
· a "U" or square type safety loop on front of drive shaft assembly is required
· stock type ignition
· stock type distributor only
· no high performance distributors or high performance parts
· no altering firing order
· must be stock for make and model
· no gear lower than 3.73
· may weld spider gears
· positraction rear ok
· shocks have to be in stock location
· no lightening of any parts
· all components must be made of steel
· stock only for make and model, stock shocks only. No performance shocks. Must have part number, will be
for make model. Stock springs for make and model
· 10" maximum arch height on rear springs
· 1/2" tolerance on front springs on stock height
PROTEST AND CLAIM RULE
· protest bottom - $600
· protest any 3 items - $300
· acceptance fee - $100
· track keeps $100
· claimer rule on transmission - $400 - may buy torque converter for additional $100
· Can use transmssion for one of the three protested items but it is a visual inspection only to check for type,
not be removed from can
· Can protest head for one of the three protested items, but can buy both heads for $500 and intake for $100
· Tech man has final say