1. The supermodified chassis (frame) must be made with sae 4130 condition “N” seamless steel tubing. This includes the chassis, all cross members and diagonals. The bumpers and nerf bars can be made from mild steel. The main frame rails, including the roll cage, must be made with 1.5” O.D. and .095” wall thickness. The cross members in the cockpit area must also be made of 1.5” O.D. and .095” wall thickness. The chassis must have adequate diagonals which must be a minimum of 1” O.D. and .065” wall thickness or equivalent. The vertical diagonals in the cockpit area must be properly spaced to prevent a front bumper from contacting the driver in the case of a side impact.
The cock pit area of the chassis, including the roll cage, must be a minimum width of 17” and a maximum width of 24” measured inside the frame rails.
The roll cage must be of a height that the top of the drivers helmet, while strapped in race position, is completely below the underside of the roll cage. A four (4) inch distance between the drivers helmet and the bottom of the roll cage is recommended.
The roll cage shall be incorporated as part of the chassis construction and shall be attached to the frame in four (4) locations to the upper frame rails. However it is recommended the roll cage up rigths connect to the lower frame rails. The roll cage uprights will have a corner gusset a minimum of 3” away from the joint, where the roll cage uprights attach to the upper frame rails, to prevent the separation of the roll cage from the frame. The gussets will be a minimum of 1”O.D. and .065 wall thickness. The roll cage must have an x brace or v brace to support the rear roll bar hoop. These braces must be made of a minimum of 1”O.D.and a minimum wall thickness of .065”. The rear roll cage hoop must have additional braces (one on each side) that extend from the upper frame rails to at least half way up the height of the rear hoop. These braces should be at a 45 degree angle and be made of 1.5” O.D.*.065 wall thickness.
2. The wheel base (the distance from the center of the front axle to the center of the rear axle) can be not less than 90” or longer than 100”.
3. The supermodified shall be rear wheel drive only. 4 wheel steering or rear wheel steering will not be allowed.
4. The 4 wheels shall be located in the standard position; left front, right front, right rear, and left rear.
5. The engine shall be mounted in the standard location; front of the engine facing forward and the rear of the engine facing rearward. The entire engine will be located in the front 2/3 of the wheel base ahead of the driver. No reverse rotation engines.
6. All components, including headers, engine, oil tank, and radiator may not extend beyond the outside edge of the tires.
7. There shall be a firewall between the engine and the driver. A steel or aluminum plate at least 1/16” thick shall be adequately fastened to the frame between the engine and the driver. This firewall must be sealed to prevent fluid or fire from coming in contact with the driver.
8. The drivers torso must be located behind the engine, to the right of the engine, and front of the rear axle.
9. No articulating chassis.
10. Streamline tubing is permitted, but can’t be used for diagonals or cross members in the main structure (center section). Below is a chart that will help enable you to choose the correct streamline tube size. The wall thickness in this case is only an example, but the comparison would be the same if the wall thickness you choose is thicker.
FRONT and REAR SUSPENSION
1. The maximum width of the front end and rear end shall be 85”. This is measured from the outside of the bead area of the wheels.
2. Independent front or rear suspensions are not permitted.
3. The front axle must be made of steel and go directly from the right side spindle to the left side spindle with no interruptions. Any type axle construction may be used. The axle may be 2 piece to prevent binding, but can’t allow the front wheels to work independently of each other vertically. Any spindle may be used.
4. The rear end can be a quick change or non quick change. Front load quick changes are not permitted.
5. The lowest gear ratio allowed is 4.12
6. The rear axle can be steel or aluminum only and must be a 3” open tube design. Titanium is not permitted.
7. The driveshaft shall be steel or titanium and should be painted white for visibility. The driveshaft shall be located outside the main frame rails, and must run directly from the crankshaft flange to the rear end flange. The driveshaft must have 2 driveshaft guards located 3” to 5” away from the joints. They shall be constructed of ¼”x 2” steel and properly fastened to the chassis or nerf bar.
8. No transmissions allowed.
9. A safety chain or cable shall be fastened from the torque arm to the chassis.
10. Streamline tubing is permitted on suspension components providing it has an adequate cross section.
11. No active suspension or semi computer controlled suspensions allowed.
12. Supermodifieds must have 4 shock absorbers, one(1) on each wheel. Shock absorbers can have no more than 2 adjusters. Any shock absorber manufacturer is permitted. Any shock canister is permitted. No knee action or rotary shocks are allowed.
13 Springs must be steel magnetic.
14. Any type suspension can be used providing it meets the previously mentioned rules.
GENERAL SUPERMODIFIED COMPONENTS
1. The supermodified can be weighed either with or without the driver. The supermodified must weigh a minimum of 1825 lbs. after the race without the driver or 2025 lbs with the driver. The maximum left side weight allowed after the race is 68%. No fuel, water, oil or weight of any kind can be added before the car is weighed.
2. Bolt on weight is permitted, provided the weight is securely bolted to the chassis. Weight cannot be bolted to nerf bars or bumpers. Weight can’t be placed on or inside
the nerf bars. Lead shot is not permitted.
3. All exhaust pipes must run into a common collector for each side. Headers may be made of either steel or stainless steel.
4. All cars shall run a fully functional Schoenfeld muffler connected directly to the ends of the collectors. Either a 10” or 11” is acceptable. No other muffler is acceptable.
5. No modified’s, small block supers, sprint cars or cars identified as such will be allowed to compete.
6. No fan type cars are allowed.
7. A 12 volt wet cell or dry cell battery is permitted provided it is securely fastened to the chassis inside the main rails and outside of the drivers compartment. The battery must have a protective cover to prevent acid from spilling.
8. No in-cockpit adjustments allowed except for brake bias and fuel control systems. This includes but not limited to weight jacking devices and adjustable shocks.
9. No radio or computer controlled devices of any type are allowed. This includes traction control and recording devices. Tachometers with memories are allowed.
10. Carbon fiber components are allowed only to provide for driver safety. Carbon fiber cannot be used in place of metal for body panels or chassis construction.
BODY DESIGN AND DIMENTIONS
1. No body panels or any other material shall extend below the bottom frame rails.
2. Wear or skid plates are allowed provided they are no thicker than 3/8” and no wider than 2”.
3. All body panels shall be made of metal or fiberglass. No Lexan, Plexiglass or transparent material shall be allowed, except for windshields.
4. The intent of these body rules is to provide for the construction of safe, aerodynamic and attractive supermodifieds. This is for the benefit of both the competitors and the spectators.
5. FRONT SECTION: From the center of the front axle to the outermost portion of the front bumper.
A. Length of the front section will not exceed 34”.
B. Width shall not extend beyond the inside dimensions of the tires.
C. A single element nose wing may be used. The wing can’t be wider than the inside of
the front tires, no higher than the bottom of the front bumper and must be behind the leading edge of the front bumper.
D. Front bumper is mandatory. The bumper shall be at least 12” wide (at its narrowest point) and no wider than 16”. The bumper shall be at least 3” high. It shall consist of 2 hoops with at least 2 front verticals. The bumper shall be constructed of 1” O.D. and .065” wall thickness or larger . All bumpers shall be mandrel bent to prevent sharp corners. The top loop of the bumper can be no lower than 13” and no higher than 22” from the ground. The lower loop of the bumper shall be no higher than 10” from the ground. If a jacking device is used it may be no longer than 2” and must point straight down.
6. CENTER SECTION: Area from the center of the front axle to the center of the rear axle.
A. Hood height shall not be higher than 2” above the steering wheel. The hood can be no wider than the outside dimensions of the chassis. A shroud to cover the throttle linkage can be used, but may not cover the sides of the intake manifold.
B. A Lexan or similar material windshield can be used providing it is not wider than
the roll cage and is no higher than 5” above the steering wheel.
C. Side body panels shall be no higher than shoulder level of the driver while the
driver is strapped in the seat. The driver shall have a minimum of 135 degrees of unobstructed vision on each side while strapped in the seat. No sheet metal shall extend into the cockpit beyond the inside dimensions of the upper frame rails.
D. Right side body panels may extend to the inside dimensions of the tires. (the inside dimensions of the tires is measured by drawing a line from the inside of the front tire side wall rearward to the inside of the rear tire sidewall.) The vertical panels may not be higher than the side cockpit panels and cannot obstruct the drivers vision. If a horizontal panel is used, it must follow the contour of the lower right side frame rail with a 1” tolerance and be a solid 1 piece panel with no openings. The front and rear edges of the panel may be reinforced for strength.
E. Left side body panels may extend 6” beyond the inside edge of the left side tires. These panels may extend further to protect the oil tank and/or oil cooler but not further forward than the rear of the engine or beyond the nerf bar. If a horizontal panel is used, it must follow the contour of the lower frame rail with a 1” tolerance. This horizontal panel may have cut outs for oil coolers or other components.
F. No body panels can be attached to the roll cage above the drivers shoulders with the exception of securing the rear body work to the chassis.
G. Nerf bars are mandatory on both sides of the car. It shall be made of steel only (mild steel is acceptable) with a minimum of 1” O.D. and a minimum of .065” wall thickness. The nerf bar shall extend to within 1” of the outer edge of the tire, but can’t extend beyond the outer edge of the tire. The nerf bars must not be further than 10” from the face of the tires and shall be at a height the same as the centerline of the axles. Each nerf bar must be attached to the chassis a minimum of 4 locations. Nerf bars must be attached to the chassis at the front, rear, and 2 positions at the center bulk head, (the bulk head behind the engine that the drivers legs go through)1 to the upper frame rail and 1 to the lower frame rail. This configuration will help protect the driver in case of a side impact and prevent the nerf bar from bending or deforming as a result of side impact which will protect the driver
H. All supermodifieds must have a continuous (1 piece appearing) flat belly pan,that will be attached to the bottom of both the left and right frame rails. The belly pan must extend the entire length of the center section, from the center line of the front axle to 18” beyond the center line of the rear axle. The belly pan can be no higher or lower than the bottom of the lower frame rails. A belly pan is also required under the engine. This pan must hold the entire liquid contents of the engine. A fire proof absorbent pad in the bottom of the belly pan is recommended to prevent a car from sliding on its own liquid.
G. Under chassis tunnels are not permitted.
7. REAR SECTION: Area from the center of the rear axle to the outer most portion of the rear bumper.
A. Length of the supermodified body shall not exceed 40” from the center line of the rear axle.
B. Rear height shall not exceed 36” from the ground with the driver sitting in the driver’s seat. This includes all body panels and fuel tanks, but does not include the head rest. A head rest is mandatory, but may not be higher than the top of the driver’s helmet.
C. Body panels may extend from the front edge of the rear roll bar uprights to the front edge of the rear wing, (with the exception of the fuel tank container which may extend to the trailing edge of the rear wing). The panels cannot be taller than 36” from the ground with the driver in the driver’s seat and cannot be wider than the rear bumper excluding rear wing end plates and rear wing support panels which may extend to the inside dimensions of the rear tires.
D. Rear wings may be used and may be free standing. The wings may not be movable while the car is on the racing surface. Any design or combination of wings may be used, up to 3 elements. The combination of wings must fit within the 22”long x 15” deep imaginary box.
E. The lower body work (under the fuel cell) must follow the contour of the bottom of the fuel cell and cannot create a tunnel.
F. A rear bumper is mandatory. The bumper may extend rearward 46” from the center of the rear axle, but must extend rearward at least 40” from the center of the rear axle. The bumper shall consist of at least 2 hoops and be constructed of a minimum of 1” O.D. and a minimum of .065” wall thickness .The bumper must be mandrel bent and have a minimum of 2 vertical tubes made from the same material. The lower hoop of the bumper may be no higher than 10” from the ground. The bumper shall be a minimum of 16” wide, but no wider than 24”.
1. Any brake manufacturer may be used.
2. Dual master cylinders are mandatory.
3. All cars must have 4 wheel disc brakes with 1 caliper and rotor on each wheel.
4. Rotors must be magnetic steel or iron only. Rotors may be ceramic coated for improved wear and stopping power.
5. Brake lines must be steel or stainless covered Teflon.
FUEL BLADDERS AND FUELS
1. All supermodifieds shall be equipped with an approved fuel bladder. No hard rubber bladders or plastic cells allowed. All bladders must be fully enclosed inside a metal container. The fuel bladder container must be completely sealed to prevent fuel leaks in the event of a bladder failure. All fuel bladders must be above the bottom frame rails.
2. All bladders must have an aircraft type flush mounted fuel cap. No flip type caps permitted.
3. All fuel cells shall have an approved check valve vent that will prevent the loss of fuel if the vehicle is involved in an accident. No homemade vents or check valves are permitted.
4. Electronic fuel pumps that supply fuel directly to the engine are not permitted. Electric or mechanical fuel transfer pumps are allowed. If an electric pump is used, it must have a clearly marked switch on the dash board.
5. Front, rear or left side fuel bladders may be used.
A. The left side bladder cannot extend beyond the inside dimension of the left side
nerf bar and must be located between the rear of the engine and the front surface of the
left rear tire. The fuel bladder and container cannot be higher than the side body panels.
B. Front fuel bladders must be located inside the frame rails and be adequately
protected from all suspension and steering components, engine heat and exhaust header heat.
C. Rear bladders must be protected by either the frame or the bumper.
6. 100 % methanol is the only fuel allowed with no additives except valve train lube providing it doesn’t enhance the specific gravity of the methanol.
2012 SAFETY UPDATES
1. All areas of the upper roll cage, that the drivers helmet could come in contact with, must be adequately padded with an approved roll bar padding.
2. All supermodifieds must be equipped with a head rest. This head rest must be properly padded. The head rest must be constructed in a manner that it can't be manually moved or deformed in any direction. It is recommended that the head rest be removable to enable the driver to evacuate the cockpit.
3.All drivers must wear a HANS or hutchens device while on the racing surface.
4. All supermodifieds must have two (2) engine kill switches. One (1) must be located on the dash board and properly marked as such, and the other must be located on the throttle peddle toestrap. A throttle toe strap is mandatory and must connect to both left and right sides of the throttle pedal to ensure it will not bend or flex. Brake kill switches may also be used but aren't mandatory as they are less effective. L shaped toe straps are not acceptable.
5. For the 2012 racing season, all drivers must wear a full-face SNELL approved helmet with the rating of 2005 or 2010.
SMALL BLOCK SUPER RULE UPDATE
1. Both steering boxes or rack and pinion steering are allowed.