2010 UMP DIRTcar West Modifieds

SECTION VIII.  CAR RULES

1.  ROLL CAGES

(A) Must consist of continuous hoops not less than 1.666 inch outside diameter and must have a wall thickness of at least .095-inch.  Low carbon, mild steel tubing is recommended, may also be constructed of 1.5" diameter chromoly or DOM tubing. 

(B) Must be frame mounted in at least six places.  No brazing or soldering allowed. 

(C) Must consist of a configuration of front and rear hoops connected by tubing on the sides or side hoops.  Driver's head must not protrude outside cage with helmet on and strapped in driver's seat.  Must have minimum of one cross bar in top halo of roll cage.  Roll cage must be securely supported and braced. 

(D) Protection of feet is mandatory.  Bar across back of engine with vertical bars and rub rails, or similar protection.  No brace bars forward of cage may be higher than stock hood height.  Main cage no further forward than engine plate. 

2.  DOOR BARS:  A minimum of three driver side door bars, at least 1.5 inch O.D., must be as parallel with the ground as possible and located perpendicular to the driver so as to provide maximum protection for driver, but without causing undue difficulty in getting into or out of vehicle.  The side bars must be welded to the front and rear of the roll cage members.  Must have at least one cross door bar, minimum 1.25 inch O.D., on passenger side of car, either horizontal or angled.  Recommend steel door plates, 18 gauge or .049-inch minimum thickness metal.  If installed, these will be securely welded to outside of door bars on driver's side.  Plate must cover the area from the top door bar to the bottom door bar and from the rear down post to five inches in front of the seat.  Steel door plates must be visible for inspection. 

3.  SAFETY: Helmets are required and must be Snell SA95, SA2000, or SA2005.  Helmet must be worn at all times car is on the track and must accompany vehicle at time of inspection.  Roll bar padding is required in driver compartment.  Fire retardant padding recommended.  SFI approved full fire suits of a flame retardant nature must be worn by all competitors.  Fire retardant gloves are required.  Neck collar or head and neck restraint required.  Fire retardant shoes are mandatory.  Full-size (minimum 16"x20") driver side window net, or arm restraints required.  Window net to be mounted so latch is at top front of window.  Five point safety belts, sub belt, shoulder harness required.  The shoulder harness must be mounted securely to the roll cage.  Seat belts and shoulder harness recommended not being more than one year old.  Aluminum high-back seats only.  Seat must be mounted inside the frame rail and ahead of the rear tire.  Bottom of seat can be no lower than the bottom of the frame rail.  Kill switch required within easy reach of driver.  Switch must be clearly marked 'OFF' and 'ON'.  360 degree drive shaft loop required and must be constructed of at least quarter inch by two-inch steel, or one inch tubing, mounted six inches back from front U joint.  Steel drive shafts and yokes only.  Drive shaft must be painted white. 

4.  ELECTRONICS:

(A) No transmitting or listening devices in car.  No electronic monitoring computer devices capable of storing or transmitting information except tachometers, digital recall telltale tachometer , or mechanical tach allowed on cars.  No digital gauges allowed on car.  No electronic traction control devices allowed.  No adjustable ignition control boxes allowed.  Only one ignition box allowed on car.  The only changes that can be made with ignition box is rev 1imiter settings, and only one high end setting is allowed.  This setting can be changed through one chip only, or an internal setting inside the box. An 8,000 RPM Rev limiter is required.   No timing retard controls allowed.  No electronic traction control devices allowed, electronic or otherwise, penalty is a loss of all points for the season and a $1,000 fine.  Penalty must be paid before driver is allowed to compete in another DIRTcar west  Series race. 

(B) Ignition system may be claimed by any driver finishing the race on the lead lap or by the track promoter for $500. Any Tach may be claimed for $300.  This includes the distributor and cap, coil and electronic control boxes, relays and modules that are wired into the ignition system.  Any driver refusing to sell claimed ignition loses points and monies for that night, lose of all DIRTcar west Series points for the season and must pay $1000 fine to the for the track's series point fund before driver is allowed to compete in another series race at any Series Track. 

5.  EXHAUST:  Exhaust system must be mounted in such a way as to direct spent gasses away from cockpit of vehicle and away from areas of possible fuel spillage.  All exhaust must go through headers.  Mufflers may be required at some tracks.  It is up to the track to state and enforce optional muffler rule.  Each racer should inquire as to the muffler rule at the tracks they wish to compete at. 

6.  FUEL SYSTEM:  Racing fuel cells required and must be mounted by at least two solid steel straps, two inches wide around cell.  Fuel cells must be enclosed in steel container and must be mounted securely behind rear axle and between the rear tires, no lower than six inches off the ground, protected by roll-cage tubing.  Protective tubing must cover the rear and extend past both sides of fuel cell.  Fuel cell must be a minimum of four inches ahead of rear bumper and no part of fuel cell shall be lower than protective tubing.  All vents must have check valves.  Fuel cells are limited to 32 gallon maximum capacity.  Pick up must not be underneath fuel cell.  A limit of one standard fuel filter allowed between the fuel cell and carburetor. 

7.  FUEL:  Fuel may be either gasoline or alcohol.  NO Nitrous Oxide or pressurized fuel tanks.  NO performance enhancing fuel additives of any kind.  Penalty of loss of all DIRTcar west Series points and a $1,000 fine.  One two barrel or one four barrel carburetor allowed; must be naturally aspirated.  NO fuel injection; NO electric fuel pumps. 

8.  BATTERIES:  One battery only, must be securely mounted and shielded.  All vehicles must have the capability of starting without being pushed or pulled.  All cars must join lineup on demand, unaided, or go to rear of that race. 

9.  WEIGHT: Loose objects and/or weights must not be used in driver's compartment or outside of the body or hood area.  Any weights added to other areas of vehicles must be securely mounted and must be painted white and have the car number on it, and attached with at least two half inch bolts.  No titanium products, parts or components allowed anywhere on race car.  No gun-drilled, tubular or hollow bolts or studs anywhere on car. 

10.  CAR WEIGHT RULE:  Each track will have the option of using a minimum car weight rule.  DIRTcar west weight rule will be 2350 pounds with driver after race.  This is an optional rule to be used and enforced at the discretion of each series track. 

11.  TIRES AND WHEELS:

(A) D. O. T. approved McCreary American Racer tires, G 60  KK704, or Short KK704 stamped on sidewall or G60 Hoosier. Tires may be regrooved and siped.  No chemical additives, softening or conditioning.   De-glazing or grinding the tread of the tire is allowed but you may not contour or round off the edges (i.e. - No cambering the tire).

(B) All wheels must be 8" wide steel wheels.  No wide five wheel adapters allowed.  Aluminum or steel spacers allowed. 

(C) Right side bead locks allowed front and rear.  External steel bead lock only and it cannot make the wheel any narrower than 8 inches and no wider than 8.75 inches.  Must use only steel bolts.  Mud plugs allowed ,inside and outside.  May weld three tabs, no more than two inches long, on wheel for mounting of mud cap.  Bleeder valves are allowed. 

12.  FRAMES:  No part of race car frame can be lower than four inches from the ground (exception is front cross member and oil pan). 

(A) Factory production complete full 1960 or newer parallel American passenger car frames only.  Frames may be cut in rear only at point not further than 36 inches from center of rear end housing.  No front clips or tube type allowed.  Maximum two inch wide by four inch tall frame stiffener may be welded directly to outside of frame rail. 

(B) Frames may not be widened or narrowed and must be able to support roll cage on both sides.  Must be full and complete both sides.  Front cross member must remain full and intact where joined at the frame rails.  Center of cross member may be notched for radiator and/or steering clearance only. 

(C) No Jeep, Bronco (etc.) or four wheel drive frames allowed.  No sports car frames allowed.  No front wheel drive allowed. 

(D) Minimum wheelbase, 108 inches, both sides.  Maximum overall width (front or rear) shall not exceed 78 inches from outside of tire to outside of tire. 

13.  SUSPENSION AND STEERING:

(A) Front suspension must be unaltered approved OEM and be in stock location, and must be replaceable by stock parts.  Outer tie rod end and adjustment sleeve may be replaced by a minimum .625-inch rod end and steel tube.  Weight jack must be in original center line of spring.  Stock passenger car spindles only; no fabricated spindles.  Spindles can be ground for brake caliper clearance only.  Bottom A frames cannot be altered or moved (exception:  can weld shock mount on A frame).  No offset lower control arm bushings.  Tube-type upper A-frames allowed and can be moved.  Aluminum or steel A arm cross shafts allowed.  Front sway bar must be approved OEM.  No aluminum or fiberglass suspension or rear end parts allowed.  Steering box must be steel approved OEM and must remain within original bolt pattern for type of frame used.  No rack & pinion allowed.  Steel steering shafts and knuckles only.  In cockpit steering may be modified to suit driver's taste, but must be kept on left side of cockpit.  No center steering allowed. 

(B) Aluminum or steel coil over kits allowed on rear only.  

(C) Rear of frame may be altered to accept leaf or coil springs; any coil spring must be at least 4.5 inches outside diameter.  Steel springs only.  No torsion bars allowed in rear.  One coil and/or leaf spring per wheel.

(D) No devices allowed that would enable driver adjustments to alter wheelbase or for weight jacking while car is in competition.  No air shocks or air bags allowed. 

(E) One shock per wheel only.  Additional shocks in other locations permissible.  No covers on suspension parts except clear cover on slider and a shield to protect the shocks.  Trailing arm mounting hole covers allowed.  Schrader valves/fill port allowed, steel body only, aluminum cap ok, no adjustable shocks, no external reservoir/canisters. 

14.  BRAKES: Brakes must be operated on all four wheels during inspection.  No brake shut-off or pressure sensitive devices allowed.  Proportioning allowed, front to rear only.  Brake lines must be outside frame rails and visible. No extra or unused brake lines allowed.  Car may be asked to pass a 4-wheel skid test or rotor heat difference test.  Front and rear lines may not go to the same master cylinder.  Vented rotors only, front and rear, no scalloped rotors.  Rotors cannot be lightened.  Rotors may be re drilled for different bolt pattern or larger studs.  Must be steel, approved OEM calipers, and they cannot be lightened.  Minimum OEM dimensions must be maintained for hubs, rotors, and calipers.  No titanium products, parts or components allowed anywhere on race car.  No gun drilled, tubular or hollow bolts or studs anywhere on car. 

15.  BODIES:

(A) 1970 or newer American compact passenger car only, no panel vans or station wagons.  Stock appearing front windshield and rear window support unit, painted roll bars not acceptable substitute.  May utilize a flat half-windshield, with no wings, mounted to the roll cage.  Mirrors not allowed.  Must have a minimum of three windshield bars in front of driver.  Cowl panel in front of driver can be no wider than cockpit and no farther back than the steering wheel. 

(B) Firewall and floorboards are mandatory.  Minimum .125-inch aluminum or 16 gauge or .060-inch steel, complete floor is recommended.  All body parts should be recognizable as factory production vehicle.  Fiberglass or metal duplicates of body parts are permitted.  Handmade body parts may be constructed of steel, aluminum, or fiberglass, but should be recognizable as a factory production vehicle.  All cars in competition must have a complete paint job, no reflective doors or quarter panels.  Deck must be the same width, front to rear, and parallel to the frame.  Recommend that lower portion of drivers' compartment be reinforced with steel or heavy gauge aluminum at the driveshaft area and rear of seat.

(C) Original roof line of vehicle must be maintained.  Must be fiberglass or aluminum full size roof. Top of doors may have a 1" lip above the deck. The roof supports may have 1" lip above the deck to roof line.  Rear roof stiffener no larger than ½" allowed and must turn down perpendicular to the ground.  No wings, spoilers or any other ground effects are allowed anywhere outside or inside car except 5 inch rear spoiler and two inch nose fins.  The rear spoiler will not exceed five (5) inches in height and not exceed five and one-half (5 1/2) inches of total material.  The measurement will be from the deck to the top of the rear spoiler.  The rear spoiler will be attached to the deck and will not exceed the width of the rear deck lid.  A maximum of four (4) supports may be installed on the front of the spoiler (see diagram 3 at page 12).  Sail panels must closely resemble examples shown on body diagram and be the same on both sides of car. 

(D) All cars must be numbered with large legible numbers on both sides, on top.  Numbers on sides and top of car must be in contrasting color from body, be at least four inches thick and at least 20 inches high.  No rear panel required. Must have minimum of 4" tall car number on spoiler for lineup recognition.

(E) Sponsors' names must not interfere with car numbers and must be neatly lettered. 

(F) Engine compartment will remain open except for optional engine side panels; hood sides may have maximum four inch drop and must be enclosed at rear of hood; maximum hood scoop height   six inches.  Passenger side of deck must be no further forward than rear of block.  No panel in front of right door to engine compartment.  No inner panels.  No car covers. 

(G) Engine side panels will be allowed for decal purposes only.  These may not extend past the back of engine block.  Must run parallel with the body of the car, perpendicular to the ground, and must be easily removable for inspection at any time. 

(H) Driver and passenger side windows must have at least 12-inch opening, measured at center of window, between the lowest point at the top of window, whether the roof or roll cage, and the highest point at the bottom of window, whether the interior or body. 

(I) Two nose fins, no larger than two (2) inches tall and no longer than the length of the nose will be allowed.  Must be bent the same side to side.

(J) Door panels may extend past engine block; the top of the door will be even with the back of the block but may gradually slope down, up to eight (8) inches past the block at the bottom. Door panels can extend 1" above deck.

16.  TRANSMISSIONS:  With motor running and car in a still position, driver must be able to engage car in gear and move forward, then backward.   

(A) All disc pressure plate style clutches or non sfi approved flywheels will be required to run a scatter shield. 

(C) Internal clutch racing transmissions are allowed with any type of bell housing.  Flywheel scatter shield suggested on aluminum bell housings.

17.  BUMPERS: Center of bumper bars, front and rear, must be 18 inches, plus or minus two inches, from ground. 

(A) Steel bumpers must be used both front and rear.  Two bar front bumpers must be mounted frame end to frame end, no wider than the width of material outside frame horns, with the bottom loop parallel to the ground.  Top bar must be directly above bottom bar so bumper is perpendicular to ground.  Must be made of minimum 1.25 inch tubing and must be able to support car if lifted by wrecker. 

 (B) Rear bumper, steel nerf bars and bodies must not extend beyond width of rear tires, and must not contain any sharp edges.  Rear bumper will be no more than two inches wider than body on each side.  Rear Bumper must protect fuel cell and line up with front bumpers.

(C) Rear bumper must resemble one of three configurations: (1) Straight bumpers can be no wider than five inches outside each frame rail, (2) If the bumper is wider than that it must be bent forward on the ends at a 90 degree angle.  (3) A bumper constructed in a loop design. 

(D) Front bumpers will be 6.5 inches apart from top to bottom. 

18.  REAR END: Any approved OEM passenger car type or truck rear end may be used. 

(A) No aluminum allowed, except lowering blocks, axle cap, and drive flange.  Fully locked differentials only.  Ford third member housings must be made of iron. Steel axles only. 

(B) Quick-Change Rear ends allowed/optional - must have steel tubes, hubs, suspension mounts, etc... no titanium anywhere.  No cambered rear ends, one piece drive flange only. 

(C) No electronic or mechanical traction control devices allowed.  Penalty is loss of points and $1,000 fine payable to track points fund. 

19.  ENGINES: No aluminum heads or blocks!  GM to use 23 deg valve angle heads only.   Must retain valve angle of 23 degrees measured with an angle finder plus or minus 2 degrees total. Measurement will be taken from valve retainers . Must measure between 40 to 48 degrees from a horizontal line above the two heads.

(A) Any American make engine may be used as long as rear of engine (bell housing flange) is mounted at least 72 inches forward from the center line of rear axle.  Engine offset must be kept within two inches of centerline of front cross member.  Engine height minimum will be 11 inches from ground to front center of crankshaft. 

(B) All engines used in competition must be able to be used in conventional passenger car without alterations.  Motor mounts cannot be removed or altered.  Castings and fittings must not be changed.  No machine work on outside engine or on front or rear of camshaft.  NO magnetos. 

(C) No total 'dry sump' systems allowed.  'Wet' system must be operative, oil coolers must not protrude above interior.  Recommend accumulators not be mounted between driver and left-side door. 

(D) Cooling system may be modified.  Any overflow tubes must be directed to the ground, between frame rails.  Radiators are to be mounted in front of engine only. 

20.  EXCEPTIONS:

Anything deemed not within the spirit of the rules by the Tech Team or Rules Committee will not be allowed.