2007 Modified Rules

BODIES

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General - The modified division over the last decade has gone from backyard built racecars to cars manufactured by racecar builders.  The cars racing at the speedway are expected to conform to the safety specifications set forth by the car manufacturer.  The following are general rules to guide the class. 

1.  All roofs must be fiberglass or aluminum with stock appearing pleated edges, one piece (roll bars exposed).

2.  Cars meeting D.I.R.T. specifications will be allowed to run.

3.  One Way Radio’s in working condition are mandatory in all modified cars effective first race of the season.  One Way Radio’s will be checked by Tech Inspectors and MUST be working. 

4.  No outside wings, spoilers, airfoils or wind deflectors will be allowed.  No double panels will be allowed that creates a wing effect.

5.  Inside body sheet metal may cover a given area one time only.  No louvers in the interior sheet metal, holes only where necessary.  Louvers allowed in hood only.

6.  No part of hood can exceed 15 degrees, nor can sheet metal have an opening or extrusion between hood and nose.  No front opened air scoops on hood.  No ram air in or outside of body.

7.  Hood scoop can not start any more that 25” forward of center of carburetor.  Hood scoop can be no wider than hood.

8.  Front wheels and tires must be fully exposed.

9.  No wheel covers, or hubcaps.  Foam inserts only may be allowed when track conditions warrant.

10.  Minimum ground clearance 2 ½”.  No fan or ground effect cars.

11.  Inner panels must be aluminum or steel.

12.  NEW STYLE BODY MODIFIEDS Same as the above body cars.

13.  64” maximum height on roof including no more than 3” deflection with no more than 15-degree angle anywhere.

14.  Roof can have no more than 3” down lip on either end (front or back).

15.  Seat and steering can be offset 2” from center.

16.  Rear deck must not exceed 45” from ground not including spoiler.

17.  Maximum height of spoiler is 5” and must be clear lexon.

18.  No part of hood can exceed 10”.  Hood must extend over radiator.

19.  Side door panels may not exceed more than 70” in front of center of rear axle.

20.  Ground clearance 6” on door panels and 8” on rear panels.

21.  No painted windows – clear windows only.

22.  Maximum roof width 52” minimum roof width 44” (DIRT style bodies).

23.  Maximum body width 68”.

24.  Rear quarter panels can extend back to 48” maximum, (measured from center of rear axle to rear of car including spoiler).

25.  Rear bumper can be no further back than 52”, (measured from center of axle).

26.  Side panels must be at least 20” in from the center of front axle.

27.  Front hood, nose and front spoiler can be no wider than 36” and may not extend anymore than 20” in front of axle centerline.  Also, they may have 2” maximum lips on sides following contour of body.

28.  Front bumper cannot be any further than 20” in front of center of front axle.

29.  D.I.R.T. legal ram air hood scoop.

30.  Sail panels allowed.  65” maximum height from ground to top of sail panel.

1.  Minimum frame width must be 26” measured at rear of roll bar.  Left and right frame rails must match each other plus or minus 2” measured from front of engine through driveline.

2.  Chassis width shall be as follows: front 24” min. 32” max; Rear 27” min., 35” max.  All measurements shall be taken from outside of frame to outside.

3.  All 2x4 frame rails must extend to the front of the radiator and extend to a minimum of 14” of the center of rear axle.  All kick up material must be same specs as roll cage or frame material.

4.  Minimum wheel base 106”.  Maximum 110”

5.  Suitable reinforcing must project from the frame to at least the centerline of the tread, and be centered 18” from the ground. 

6.  Rub rails must be outside body panels but can be no more than 2” maximum outside of tires.

7.  Open wheel cars only.

8.  All bumpers must have an 18” center measured from the ground.  Front bumper not to exceed 20” in front of center axle.  Front bumpers must be minimum 6” vertical height between bumper rails.  Rear bumpers must be minimum 10” in vertical height to extend to center of tires maximum outside tires.  Bumper must have rounded ends with no sharp edges.

9.  Only 1 ¼.095 minimum tubular steel for front bumper.  Nerf bars and rear bumper minimum of 1 ½.095.  No bracing less than 1 ¼.

8.      One bar only behind rear wheel.

1.  Rear end of chassis must not be offset anymore than 4 in. from center of the inside tire width, measured from the inside of the rear tire to the inside of the right tire, at axle height.  Front end same.  Maximum outside tire width 88in., minimum 74 in.

2.  Conventional or live axle quick change rear end.

3.  No independent suspensions

4.  Only 2 Universal joints per drive line.

5.  All suspension systems must be mechanical with no form of electrical assistance.

6.  Fuel cell mandatory – 36 gal. Maximum.

7.  All cars must have locked rear ends.  No limited slip, posi-traction, or traction controlled differentials allowed.

All cars must have four-wheel brakes able to work upon request.  All components must be in place.  (Caliper- rooter- hose- etc.)  Remote brake shut-off allowed.

1.  Only American manufactured Engines, (GM, Ford, or Chrysler products).

2.  467/358 cu. in. limit will be maximum displacement use with 3 cu. in. wear allowance.  Cast iron blocks only.

1.      Engine limited to one American manufactured carburetor not to exceed 4 venturies and (1) 4-barrel intake manifold.  No fuel injection or blowers.  Outside carburetor body must remain stock.

 No in line veturies.  No fuel or air shall enter engine by any other means other than stock operation of carburetor.

4.  Fuel- Gas or alcohol allowed per weight and engine spec.

5.  Fuel shut-off mandatory in reach of driver.

6.  No mechanical turbo chargers or superchargers.  Normally aspirated engines only.  No overhead cams.

7.  Any kind of ignition mechanically driven in stock position. 

8.  No dry sump oil system unless center of crank has 11” clearance to ground.

9.  Car must have self-starters, neutral and reverse gear in operating order.  Approved American manufactured transmission only, standard or automatic and must bolt to bell housing.

10.  Self-starter must be in working order.  All cars must be able to leave pits and starting line under their own power.

11.  From a neutral position with motor running a car must be able to go forward and backward.

12.  Only one (1) radiator and must be centered in front of motor in a vertical position.  No auxiliary cooling tanks allowed in driver’s compartment.

13.  Engine must not be offset any more than 4” from center point of front wheels (measured from front or back of crankshaft) and placed in an upright position or setback any more than 42” (measured from the center of front axle, king pin or ball joint to front face of block). No rear engine cars.

14.  Crank triggered ignitions are options.

15.  Alcohol cannot be used in any engine larger than 358.  Everything else will be on gas.

1.  McCreary American Racers

Left rear tire: McCreary American Racers (Must be stamped)  33 or 44

Right rear tire: McCreary American Racers (Must be stamped) 38 or 48

Left front tire: McCreary American Racers (Must be stamped) 33

Right front tire: McCreary American Racers (Must be stamped) 33

If you run a 48 on the right rear, you must run a 44 on the left rear.

Buffing, cutting, grooving, or sipeing will be allowed.  No tires softened.  Tires will be checked with durometer on scales after feature events.

Locked in tire prices for the season will be posted at the track.

2.  Aluminum or alloy wheels allowed.  14 max. on wheels.

3.  No plastic wheels – no carbon fiber wheels.

4.  Bleed off valve allowed.

PLEASE NOTE: Any post race tear-down on cars in this class must have finished in the top five, including the car of the protester. Protesting car MUST also submit to the same tech inspection as that of the car being protested. This type of procedure will prevent any unnecessary “grudge” tear-downs of cars. A $200 tear down fee must be presented to head tech inspector by protesting driver along with written protest no more than 10 minutes after completion of feature.