M.A.D.C.R.A. RULES OF COMPETITION 2004
TRACK RULES SUPERSEED ALL MADCRA RULES
1. Body Styles
A. 1928-1948 American made production vehicles only. 5/8 scale two-door sedans, coupes, or pickup trucks. NO Modified Lites.
2. Body Requirements and Specifications
A. Body must be 5/8 scale, stock appearing. Maximum outside tire width 60 inches. Wheel base 73
inches +/- ½ inch.
1. Must have grill shell or simulated open radiator matching original body style, any
2. Doors, windows, and cowlings must retain stock appearance. Hood louvers allowed for
Cooling, but must maintain stock contours.
3. Engine compartment must conform to scale and match contour of body.
4. Must have trunk lid or trunk access panel conforming to original bodylines.
5. No fenders
6. No wings or spoilers.
7. RAM AIR induction system prohibited.
B. Body will be metal construction, 26-gauge steel or .040 aluminum minimum. Fiberglass or plastic grill shells allowed. All exposed edges must be folded or trimmed over. Legend cars may be allowed under local rules. NO Modified Lites.
C. NO open top cars (roadsters or convertibles) NO panel trucks, station wagons, or specialty cars.
1. No car over 50 inches tall, top to ground. Body height maximum 42 inches, bottom edge to top (including frame rail) Maximum outside tire width 60 inches
2. Maximum body width 38 inches.
3. Body contour must be formed by frame and roll cage.
4. Frame ride height must not let car bottom out on track.
E. Doors must be operational and equipped with secure latch.
F. Fasteners on hood, trunk, or panels must be positive locking type.
1. All cars will weigh a minimum of 1240 lbs with driver after race. Empty car weight
minimum is 950 lbs (no ballast, no fuel).
2. Added weight must be painted white and marked with car number. Weight mounted to
frame rails must use two 7/16 bolts and double nuts. No weight outside of car body,
i.e. on nerf bars.
H. Bumper dimensions
1. Front bumper must not be wider than 30, not less than 6 high, and will not be more
than 8high, and will not extend more than 12 forward of front tires.
2. Rear bumper must not be wider than 56, not less than 6 high, and not more than 8
high, and will not extend more than 6 behind rear body panels, and must have 3 vertical bars.
3. Front and rear bumpers must be at least 4 off of the ground, and no more than 14
above ground. No sharp edges.
I. Firewall must be metal or aluminum with a minimum thickness of .050. Engine protruding
into cockpit must be enclosed.
J. Windshield must be Lexan, wire mesh, or protection bars. Lexan highly recommended when
running asphalt. No glass. Windshield bars are required. Minimum of three, must be steel.
K. Dashboard must be metal. Should have push/pull electrical switch on extreme right hand side,
or master electrical switch clearly located and marked. Other switches must be toggle type.
L. Kick-outs must be a minimum of 3-point mounted ahead of rear axle. Full length nerf bars
between front and rear tires are strongly encouraged from a safety standpoint, may not extend
out beyond tread more than 1 at the rear only.
M. Seat must be high-backed aluminum, racing type. All cars will have a permanent bar located
behind top of seat at shoulder level. Bottom of seat will not be more than 63 inches
back measured from upper ball joint. Seat may be tilted back for added driver head clearance, however
no portion of the seat may be back more than 68 inches as measured above.
N. Numbers and graphics
1. Car number must be a minimum of 12 inches in height with a 2-inch stroke. Must be
Displayed on each door and roof or trunk. Numbers in four-inch size should be on front
and rear of car to help with line-ups.
2. The year and make of body style should be displayed in 1 ½ letters.
3. Car should display engine model and displacement
3. Wheels and Tires
A. Steel wheels only, minimum wall thickness .090 inches, 13diameter only. Wheel width 8 max.
B. No Bead lock rims allowed
C. McCreary 215 tires only at Boone and Stuart speedways. (Hoosiers may be allowed at other tracks, call first to see what tire is mandated at track)
D. Must run same size rim on axle.
4. Engine Specifications
A. Motorcycle engines, regular production (500 + units) only.
B. Displacement maximum: 1250cc (+1%) 4 cycle only, 4-cylinder maximum. Car should display engine type and displacement.
B1 Down draft motors are limited to 1200cc maximum with no variance.
C. Must have working transmission, clutch, and starter with all parts in place.
D. Charging system optional.
E. NO auxiliary starters.
F. Engines must be front mounted in engine compartment.
G. Engine setback: The square of the engine (rear fins of the jugs) may not extend
H. rearward more than 17 from the center of front axle. No part of the engine or transmission may
I. extend rearward more than 21 inches from center of front axle.
J. No fuel injection (except factory OEM), NO turbos, NO nitro, or nitrous oxide.
K. Engine must be cooled by original intent. May use extra fan or oil cooler. Engine lubrication open.
L. Carburetors and cams open.
M. No aftermarket cylinder heads.
N. No porting or polishing of the cylinder head. Port matching limited to 3/16 inches into cylinder head.
O. Casting/parting lines must be visible upon inspection.
P. Engine exhaust must be installed so as to not detract from stock appearing hood. Mufflers recommended.
Q. The exhaust must conform to 103 decibel ruling at 75 feet (different tracks may have a lower decibel rule) i.e.
R. Iowa State Fairgrounds is 100 decibels.
S. Maximum cylinder cranking compression is 220 p.s.i. per cylinder, measured with reliable gauge, 15-45 minutes following feature event.
T. Manufactures Engine Identification number (Serial Number)must be on engine block in its original location, and must not be altered in any way
U. Engine must be in production for 2 model years before deemed legal for use
5. Battery, Fuel System
A. Battery and fuel pump must be mounted outside driver compartment. Battery must be secure and
held with non-rubber strap. Electric fuel pump allowed. Car should have master electrical switch, clearly located and marked.
B .Fuel cell mandatory, maximum 5 gallons, located in trunk.
C. Gasoline, CAM-2, or alcohol only, according to local preference. No fuel additives allowed.
D. Cars on alcohol must display an A near fuel cell.
E. Direct manual battery cutoff (Recommended).
6. Drive Train
A Must use steel drive shaft from transmission to automotive rear end. Minimum 2.50 x .083 or
2 X .120.
B. No quick-change rear ends allowed.
C. Drive shaft must be painted white or Day-Glo orange.
D. Drive shaft tunnel must have a minimum of 3 360 degree hoops between firewall and seat back. must be fabricated of minimum .1875 x 1.5 steel bar. 1.25 x .095 steel tube highly recommended.
Fra Frame and Roll Cage
D. A. Main frame members will be a minimum of 1 inch x 2 inch x .120 wall rectangular steel tubing
only. No aluminum allowed in cage or frame.
B. Main frame will have a minimum of 3 cross members between firewall and back of seat. Cross
bracing in floor under driver strongly recommended.
C. All roll cage components including uprights and cross members must be steel, minimum size 1.25 x .083
(.095 recommended) in all cars
D. Rear door post must be minimum 1 x 2 x .120 rectangular steel or structural equivalent.
E. All cars must have bars installed across door openings on both sides. Bar should be welded in place as part of
roll cage. Minimum size 1 x .065 (1.25 x .083 recommended). Cars with full-length doors should have full door frame and a minimum of 2 horizontal cross bars. Minimum 1 x .065. Cars with full length doors must have Ό x 2 steel stops welded on each side of opening totaling a minimum of the 4 inches on each end of door. Steel plate on drivers door bars recommended.
F. It is required to have a steel bar with a minimum size of 1 x .065 inch from door post to door post under the dash.
G. It is recommended that, if using rivets, body panels should attach to tabs welded onto cage instead of drilling multiple holes into cage bars.
A. Front suspension must not extend rearward past the most forward panel of the firewall. May be
hidden under frame rail, out of view from either side.
B. Rear trailing arm/radius rod specifications:
1. Arms located outside frame rails may not extend forward beyond rear door post.
2. Arms located inside frame rail are not restricted in design or length.
3. Torque absorbing devices are permitted.
C. Wheel offsets are allowed.
D. Hub offsets are NOT allowed. Hubs must be an equal distance from frame rail on both sides of car
E. Coil over shocks are the only means of supporting the chassis. One shock and spring per wheel
F. Shocks must be of all steel construction, non-adjustable type. May not be of a type that allows
G. No driver shall have the ability to adjust suspension from inside the car.
H. Straight front axles are prohibited.
I. No leaf springs or torsion bars allowed.
J. No birdcage type rear linkage.
K. Anti-roll (sway) bars permitted front or rear
A. All steering components must have safety fasteners such as cotter pins or self-locking nuts.
B. Manufactured quick-release steering wheel hubs mandatory.
C. Rack and pinion steering is recommended
A. Four wheel brakes are mandatory. .Can have right shut off.
B. Rotors and calipers:
1. Steel rotors mandatory.
2. Steel OEM calipers or Wilwood Dynalite single calipers or equivalent. Maximum
C. Adjustable brake bias allowed.
D. Competition type master cylinders allowed.
11. NO radios
12. NO mirrors allowed
The rules and/or regulations set forth herein are designed to provide for the orderly conduct of racing events and to establish the minimum acceptable requirements for such events. These rules shall govern the condition of all events, and, by participating in these events, all participants are deemed to have accepted and complied with these rules. No express or implied warranty of safety shall result from publication of or compliance with these rules and these regulations. They are intended solely as a guide for the conduct of the sport and are in no way a guarantee against injury or death to a participant, spectator, or official. Any interpretation or deviation of these rules is left to the discretion of M.A.D.C.R.A. and the decision is final. No express or implied warranty of safety shall result from such deviation of specifications.
Changes for 2004 are in Yellow.