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Irwindale Speedway October 26, 2013 Demolition Derby Rules

(Edited from WGAS 2013 Rules) Posted February 27, 2013

The derby is open to any American made passenger car. Full framed Chrysler Imperials {1966 and older} are not permitted. No trucks, vans, suburbans, or commercial vehicles.

Section 01 Car Preparation

(a) All glass must be removed. Windshield OK.

(b) Flammable materials inside the car must be removed. These include the carpet, the rear seat, and interior trim including side and roof liners. Trunks must be free from any debris. The inside of the doors must be clear of all glass and debris as well.

(c) All light covers/bulbs, side mirrors, hubcaps, grills, side chrome, plastic, door handles and pot metal must be removed.

(d) All trailer hitches, related brackets, reinforcements and hardware will be completely removed.

(e) Stock fuel tanks must be removed.

Section 02 Fuel Systems

(a) A limited capacity (of 6 gal. or less) metal tank or boat tank is required as a replacement gas tank. You must solidly mount it in interior of the car, ahead of the rear axle. The tank must be located at least 12” from the inner door panels. The stock tank must be completely removed. If using a boat tank, you must have it placed in a metal frame or securely fastened with metal strapping or chain.

(b) Gas lines and fittings must be leak proof. No exceptions. Rubber fuel lines located inside the

passenger compartment must run through a second larger hose such as a garden hose to prevent accidental spillage on the driver in case of a leak. A hole must be made in the floor board for fuel runoff.

(c) Electric fuel pumps are optional. If an electric fuel pump is used, you must have an on/off switch that is positioned so that up is on and off is down. The switch must be easily visible and "off" must be clearly marked.

(d) Gas tanks may not be bolted to the frame in any fashion. Gas tanks MAY not be used as a kicker to keep the frame from dropping or moving forward or backward. Subject to Tech Approval.

Section 03 Batteries

(a) Batteries must be re-located inside the car. Your battery box must be fully enclosed and securely fastened to the floor. In NO way may it be connected/bolted to the frame. The lid

must be securely fastened shut using 5/16" bolts or 2" straps. (i.e. seat belts). (B) Two (2) batteries maximum

(c) Switches or wires used for powering off the car must be within reach of the driver while harnessed in.

There will be no acceptable excuse for not being able to turn off your car in an emergency situation.

Section 04 Safety Bracing

(a) A front cross brace must be installed above the steering column from window post to window post (in the former position of the dashboard). It must be made of a minimum 2" pipe or square tubing with 1/8"

wall thickness and be securely fastened into position. The dash bar in no way may touch or be bolted to the floor or the frame of the vehicle.

(b) A rear cross brace must be installed from side to side behind the driver as close to the door post (B-pillar) as possible. It must be made of a minimum 3" pipe or square

tubing, with plates welded on the ends. Optional: If floor boards are rusty, you may run MAX 2" Pipe or square tubing over to the inner rocker panel sheet metal. It must be welded, no bolting of this bar! This bar MAY NOT be welded to the frame!!

 (c) Both front doors must be reinforced with a minimum 8" wide, 3/16" thick channel iron Square Tubing or Pipe. The side iron must not be more than 6’ in length.

Section 05 Seat and Seat Belts

(a) Approved safety harnesses or functioning OEM belts are mandatory. They must be mounted to stock mounts or have a 2" minimum flat washer where it is mounted through the sheet metal.

(b) Seat can be OEM stock of any make/model car. A headrest on the upright behind the drivers is mandatory if the seat was not equipped with a headrest.

(c) No fiberglass/plastic racing style seats

Section 06 Building, Welding & Securing


(a) Doors: You may fully weld the doors. You may use filler no larger than 2"w X 1/8"t or 3/8" re-bar or equivalent. If bolting the doors shut, you may use up to 4 1/2" bolts per door. If chaining the doors shut, you may use 1 chain, no larger than 3/8" per door.

(b) Trunk lids, tailgates and hoods must be secured shut with bolts, chains or welds as follows:

(i) Hoods can be bolted in a maximum of 6 places other than stock, in which only 2 may go to the frame. Bolt size must be a minimum of 5/8" and a maximum of 1". MAX plate size is 6" x 6". Bolts must not exceed 4" above the vehicle surface. HOODS MUST BE OPENING FOR TECH!! NO EXCEPTIONS!

(ii) Chains must be a minimum 3/8" & maximum of 1/2" welded type. A bolt no smaller than 3/8" &

maximum of 1/2", with washers, must connect the chains.

(iii) Trunks may be fastened in a maximum of 6 places using chains, bolts or welds of which only 2 may go to the frame. Welds cannot be more than 6" long or if using flat plates, they must not exceed 6" x 2"x 1/8" in each place. If bolting, plate size cannot exceed 6''x6''. All thread (1" max) may go through frame or be welded to the side of the frame. Cars must have an inspection hole in the trunk.

(c) Bumper swaps are allowed, however you must use factory hardware (brackets/shocks) that either came with the bumper or came with the car you are putting it on. You MAY NOT use both!! Any tech.

(d) Front and rear bumpers may be welded solid. (I.e.-bumper to bumper shock, shock to bracket and bracket to frame) No extra metal.

(e) Bumper shock itself may be collapsed and welded. No added material.

(f) You may weld outer skin to inner structure of bumper.

(g) Frame seams may be welded from the firewall forward. You may only weld the top seam. Width of the weld will not exceed 1/2''.

Section 07 Window / Window Screen

(a) A protective screen of ½" wire mesh or smaller may be installed in front of the driver. A car with a sunroof is allowed as long as the opening is securely covered with sheet metal and deemed safe by tech officials.

(b) A maximum of 2 3/16" thick x 2-1/2" wide flat stock must be installed down the center of the windshield from top to bottom. Window bars may be bolted or welded with a minimum of 5/16'' and maximum of 1/2" bolts. No sheet metal screws allowed fastening window bars.

 (c) Optional rear window bars may be added no more than 6" extension on roof and in no way contact the deck lid, trunk pins, trunk plates or frame. They may be no bigger than 2-1/2"x 1/2" inch thick flat stock. Max 2 each parallel with roof. Window bar(s) will be bolted or welded with a minimum 5/16'' and a maximum of 1/2" bolts. No sheet metal screws may be used to fasten window bars.

Section 08 Radiator

(a) No cooling system other than stock is permitted. Radiators and/or fans can be removed. Expansion tanks must remain in engine compartment as close to the stock location as possible. Radiator support or radiator attachment will be no stronger than stock. Tech decision is final.

(b) Transmission coolers other than stock, if used must be in an enclosed box inside the vehicle.

(c) Transmission coolers and components may NOT be bolted to the frame in any fashion. Transmission coolers are NOT to be used as a kicker to keep the frame from dropping or moving forward or backward!!

Subject to Tech Approval.

Section 09 Motor Mounts / Suspension

(a) Motor mounts and transmission mounts may be strengthened with bolts, welds or chains. Motor straps welded to the frame and bolted to the motor are allowed.

(b) Any 5 lug rear end may be used.

(c) Upper/Lower control arms maybe shortened or lengthened to achieve pinion angle. You may NOT reinforce the rear end control arms (trailing arms).

(d) Leaf conversions are NOT allowed on non factory leafed cars. Suspension must remain stock.

(e) Maximum of 9 leafs.

Section 10 Distributor Plates

(a) Distributor protectors allowed must be attached to engine and transmission only. Be no wider than 10 inches, must not contact dash bar before, during or after the event. If you run a DP do not mount your dash bar closer than 5 inches behind the rear most point of the firewall/cowl. It may not be welded, bolted or connected to body, hood or frame. Forward supports must be inside normally positioned headers and not extend past the water pump.

(b) If using an engine cradle, it must not be connected to the distributor plate.

Section 11 Exhaust

(a) Stacks must be a minimum of 18" from exhaust port.

Section 12 Carburetors

(a) You must have either an air cleaner or suitable flame arrestor. Two large holes, at least 6" in diameter, must be put in the hood for fire extinguisher access. Stack holes are acceptable for fire access holes. No alternative starting methods i.e. stating fluid etc....

Section 13 Brakes

(a) Cars must have a minimum of two working hydraulic brakes.

Section 14 Tires/Wheels-Tie-Rods

(a) Any tire may be used. Doubled and forklifts are ok.

(b) Wheel wells may be trimmed. No shackles or reverse spring shackles will be allowed.

(c) Valve stem protection is permitted.

(d) Tie rods may be reinforced. Must have stock tie rod ends. No pipe ties rods.

Section 15 Sign Boards/ numbers.

(a) Car numbers must be clearly visible on the car in a contrasting color. Numbers must be a minimum of 18 inches in height mounted on roof.

Section 16 Repairing Damaged Cars

(a) When repairing damaged cars, you may use for four (4) 4''x4''x1/8'' plates per frame section. Pieces cannot be any closer than 3". They may not attach to each other in any fashion. Repairs pieces must have an inspection hole drilled in the center of plate.

Section 17 options.

(a) You may cut firewall for distributor clearance. You must cover with tin or thick rubber material.

(b) You may clamp leaf springs, 4 clamps per leaf. 2"x1/4" MAX, two 3/8" bolts per clamp.

(d) Body mounts may be removed. If replacing bolts, you may use bolts/all thread no larger than 3/4", MAX 3"x3"x1/4" washer/plate. Washer may not cover body mount hole on exterior of frame. Must be able to see in the frame. NO EXCEPTIONS!!! In addition you may add two (2) body mounts. No larger than 3/4" bolts/fasteners. MAX washer size is 3"x3"x1/4". Must be brightly painted for easy viewing.

(e) You may re-bolt hood skins. 15 bolts maximum. 3/8''max bolt size. 1" max washer size.

(f) You may re-bolt wheel wells. You are allowed 5 3/8" bolts with 1" diameter washers per wheel well.

(g) Fire extinguishers ARE mandatory. The fire extinguisher must be securely mounted and within drivers reach.

(h) You may chain the humps. You will be allowed 1 wrap of chain. It may go around the rear end 1 time and up through the body and around the frame 1 time and be bolted together.

(I) All cars should be brightly painted.- This is for the promotion of the sport.

These rules are designed to offer a fair and unbiased opportunity for all drivers to compete on an equal level.

To see the WGAS callendar of events go to