I-25 Speedway 2018 MINISTOCK Rules 


  1. No equipment on a racecar will be considered as having been approved because of having passed through inspection "unobserved". If this rulebook does not specifically state that a change, modification, or addition is legal, then a competitor must consider that change, modification, or addition as illegal. If a question arises about the legality of a change, modification or addition that is not covered in this rulebook, the question must be answered by I-25 Speedway in writing, and that decision is final.

  2. Registration: Ministock drivers must turn in a fully paid and completed current year Registration Form with properly assigned car number and pit stall, as well as a current W-9 form prior to competing in any event. (Including but not limited to qualifying races.) Every effort will be made to assign the driver with the pit stall they requested, but 1-25 Speedway reserves the right to move any car to another pit of equal construction (when permissible) at any time. Any car not in their assigned pit spot will be fined $50. There will be no duplicate numbers and/or letters used.

Check Policy: A returned check fee of $30 will be payable in cash prior


1. No stock, ga tanks allowed. Racing cells are required and must be mounted b    at least tw
steel straps,_2  wide around the cell or with a 1" box tubing. Fuel cell must be encl;sed ina    o

metal container, and  be protected  by the roll cage• Theut  bm'
g w1·11h  ave no more than 6" between protective rails on both sides of the fuel celJ protective box. Fuel cells must have check valves and approved foam bladders. Metal fuel filters only, no glass or plastic. Fuel lines are to be enclosed in meta/ conduit from the rear firewall to the front firewall inside the interior of the car. All fuel cells will be grounded at the filler collar, to a hard ground point. Ministock classes MUST run I-25 Speedway approved racing fuel, purchased at the track. No nitrous, alcohol or gas additives allowed.



2. A 4-post roll cage, securely fastened to the frame is required, made of 1.5" outside diameter steel tubing, minimum 0.095-i 11ch wall thickness. No galvanized pipe, threaded connections, or square tubing allowed. A minimum of 2 door bars on the passenger side and a minimum of 3 door bars on the driver's side. Driver's side roll cage must arch outward to the side panel. 1/8" steel plate welded from the forward bar adjacent to the driver's knee and rearward to the support bar behind the driver's seat. Plate wi II completely cover the door bar area of the cage preventing foreign objects from  puncturing the driver's area. The cage must have a triangulation  at left comer and across top loop, made of the same material as the roll cage. Roll cage must be padded at all points within driver's reach. This includes all areas along lower area of cage where driver's left leg and ankle are positioned. Entire roll cage must be inside the car. A front loop is allowed and must not stick out past the bumper. All cage points of connection must be fully welded, with no open areas allowed for water to enter and cause rust. Additional gusseting and triangulation of cage is HIGHLY RECOMMENDED. Officials reserve the right to inspect cages of all cars after accidents to ensure safety. Paneling used inside of the car must be removable to ensure safety. Paneling used inside of car must be removable to ensure cage compliance, and to inspect for illegal perfonnance items. Reinforcing of sub-frames is recommended. No full frame tubular chassis allowed. Off set reinforcing or off set roll cages will be permitted, but all cars must meet 56% left side weight upon completion of a main event, including driver.


2.1 Kick off bars are optional. Outside of the bars should be no more than 2-inches from the body. Bars will not extend past the front or rear wheels and must be in line with the center of front and rear wheels. Bars will be tapered to prevent the "hooking" of other cars. No sharp edges are allowed. Kick off bar must consist of one bar no greater in diameter than 1.5". Front loops designed for protection of the radiator must attach to the bumper and must not be higher than the lowest point of the hood, and must not exceed the width of the frame rail.


3. Bodies will be unlimited. No convertibles, sports cars or trucks. Front windshield is mandatory and must be made of Lexan (no glass) with a minimum 1/8" thickness and must be securely fastened. 3 evenly spaced I" metal safety straps are required for all windshields. No car will be allowed to compete with a broken, discolored or fogged windshield or rear window. No items may be allowed to protrude outside of the vehicle body. No outside chrome, plastic, or lenses.


3.1 Glass is NOT permitted. After market bodies are allowed. Damaged sheet meals must be repaired and painted before the next competitive race.


3.2 All quarter panels, doors, and fenders must be securely welded, bolted or riveted. No sheet metal screws allowed anywhere.


3.3 NO chains are allowed for securing doors.


3.4 Firewall and floor pan will remain stock. If other than stock firewall is used, it must meet thickness and dimensional specifications of a stock firewall. All holes will be covered to protect driver.


3.5 Rear wheel wells may be fabricated from aluminum stock.


3.6 Aluminum doors are allowed.


3.7 No louvers, hood scoops, or holes cut into hood for air cleaners. Any ground effects must meet ride height requirements. Body may not be lowered or cut to create less drag. Hood must fit flush over the engine and even with the fenders. NO tilting of the hood for cooling purposes. Any spoilers must be no wider than the width of the car and must be less than 6" in height.


3.8 Bumpers must be securely fastened and not lower than axe! centerline, measured at lowest point of bumper; and no higher than 6" above the axle centerline. No bumpers shall protrude more than 7" from the body. Bumpers will be bolted or welded to the car. In the event of an accident, tech officials will decide on the care bumper safety. Chains or cables must be attached to the bumpers and then to the frame to lessen the chance of foreign objects on the track. Chains or cables will not be less than 1/8" in diameter. Position the chains or cables on the frame in such a way that it will not allow a bumper to hang below stock location. All fabricated bumpers are allowed, as long as they are the same dimensions, height, width, and depth of a stock bumper. If the front wrap is removed from the car by accident, one week will be given to make the proper repairs. Damaged sheet metal must be repaired and painted before the next competitive race.


4. Chassis, suspension and steering components will be OEM and family to family.


4.1 NO traction bars.


4.2 No independent rear suspension.


4.3 No cutting of the upper and lower control arms. NO exceptions.


4.4 Coil cars may modify upper tower for alignment purposes only. Upper tower must remain in stock location and must have stock measurements. Care must have a minimum of 3" ground clearance at the lowest point of the car. NO exceptions.


4.5 No modifications are allowed to the front cross member to achieve ride height. Leaf springs shackles shall not be adjustable. If used, the hole used to mount the leaf springs must be tack welded. Sway must be mounted under frame in stock location with equally lowering clearance for oil pan. Must mount on top of lower control arms. Sway bars can be adjustable at outer ends of the bar to lower the control arm only.


4.6 No adjustable shock or spring spacers. Rear lowering blocks only. No other forms of "weight jacking" equipment is allowed. Upper springs mount holes must be exposed to inspect such devices. This rule is for most mustangs, where upper mount is covered with reinforcement loop. Shocks must be in stock location and mounted in the factory holes or studs. No exceptions. One stock per wheel.


4.7 No coil over or air shocks. Mustang from shock location may be attached to front loop with the stock mounting attachments and may not exceed 2 degrees from the stock strut locations. All sheet metal will be removed to expose shock locations.


4.8 Racing shocks permitted. No altering of wheelbase. Wheelbase must measure equal, on both sides within l ". All brake components are to remain in stock.


4.9 OEM master cylinder is mandatory.


4.10 No balance bar pedals are permitted. Brake bias adjusters are optional. All cars will have functional four - wheel brakes. Tech reserves the right to inspect at any time.


5. Engine must remain family to family (i.e., Toyota to Toyota) normally aspirated only. No rotary engines. Engine must remain in the stock location. All Ministock cars will be composed of front engine, rear wheel drive compact cars. This class requires 4-cylinder - 2550 or fewer engines with two valves per cylinder.


5.1 Minimum weight will be one pound per CC with driver (maximum 56% left side weight). Right front fender must show engine size used. Stock crank shafts and stroke only. No lightening