Updated: January 9, 2013

This class is all about the factory standouts meeting up to decide which car is the biggest and baddest!


Purse for this class is $3,350/event and broken down as follows:

Winner: $1,250

Runner Up: $800

Semi: $350

Quarter: $150


DESIGNATION: SCS or SuperCar Showdown followed by the driver’s competition number which must be at least four (4) inches tall and displayed on both side windows, the upper left area of rear backlight and the upper left area of windshield as seen from outside the vehicle.

FIELD: The eight (8) quickest qualifiers based off elapsed time will compete on a Sportsman Elimination Ladder Schedule, without handicap start, utilizing a four-tenths of a second (0.400) ”Pro Tree” starting system with “AutoStart” enabled. All qualifying and elimination rounds will be contested at a distance of one-eighth of a mile, (660 feet).

VEHICLE ELIGIBILITY: Any production automobile is eligible for entry in the Xtreme Drag Racing League (X- DRL) SuperCar Showdown. Vehicles which are constructed to accurately represent available production models are permitted. Constructors must apply to the X-DRL Technical Services Department with verified specifications from the Original Equipment Manufacturer (OEM) for each model including, but not limited to, engine, body, chassis and transmission information to be used in validation and authentication for eligibility unless details for the considered model are already on file with the X-DRL. All measurements herein are related in terms of the National Institute of Standards and Technology (US) system. Conversions to the International System of Units (SI) Metric system are permitted to the nearest unit of measurement. All rules are subject to change at the sole discretion of the X-DRL Technical Services Department.



BODY: All OEM vehicle production bodies must be model year 2011 or newer with the following exceptions:

All 2008-2010 Ford Mustangs All 2008-2010 Dodge Challengers

All 2008-2010 Dodge Chargers All 2010 Chevrolet Camaros

All 2010 Chevrolet Corvettes

NOTE: Beginning on January 1, 2014, all vehicles must utilize a currently manufactured OEM production body no older than five years.

All OEM production bodies must be unaltered. Exterior paint colors, paint schemes and graphics other than those available from the OEM are permitted. All OEM vehicles produced with convertible tops must compete with the convertible top raised and secured in the full coverage position. All vehicles must retain a production stance at rest. Modifications to front or rear vehicle height are prohibited. The lowest portion of any fender rocker panel may not exceed the height of the centerline of the rear axle. All OEM body mount insulation may be replaced with solid mounting hardware of equal dimensions. No OEM item on any vehicle may be replaced with an item constructed of lighter material without the prior written approval of X-DRL Technical Services Department.

BODY, Aerodynamic Aids: All equipment designed to assist or enhance vehicle aerodynamics is restricted to the complete and specific OEM production aerodynamic equipment for the vehicle model utilized. All aerodynamic equipment or devices, including but not limited to flared body panels, air dams, air spoilers, wings, spill plates, ducts, diffusers and vortex generators, must be production equipment from the OEM or an X-DRL-accepted partner of the OEM. All fixed elevated wings, spoilers and air dams must retain the original OEM mounted position, location and angle. All active electronic elevated wings or spoilers may not exceed the maximum variation of activity dictated by OEM specifications.

BUMPERS: All OEM vehicles must retain all OEM exterior collision panels including, but not limited to, bumpers and guards. The external appearance of the vehicle must remain as delivered from the OEM. All OEM exterior collision apparatus, including braces, guards, collision-avoidance sensors and energy-absorbing equipment may be removed.

DOORS: All vehicle doors, including the driver door, passenger doors, rear doors and hatches, must be functional and operable from inside and outside of vehicle.

FENDERS: All vehicle fenders must remain in OEM configuration. The front and rear, (but not the top), of each wheel well opening may be modified no more than two (2) inches for tire clearance. All fender wheel wells must remain in OEM configuration. Exhaust header intrusion areas within the wheel well may be trimmed no more than two (2) inches around the exhaust header tubes.

FIREWALL/BULKHEAD: No alterations are permitted to the OEM vehicle firewall and/or its configuration or the OEM forward bulkhead of a rear/mid-engined vehicle without the prior written approval of X-DRL Technical Services Department. All vacant areas remaining after the deletion of non-essential equipment including, but not limited to, OEM heaters, OEM air-conditioning units and accompanying OEM fan motors must be covered by panels of steel, (0.024 inches minimum thickness), or aluminum, (0.032 inches minimum thickness).

FLOOR: The OEM floor panels may not be altered or repositioned from the specific OEM vehicle design unless the revision or reconstruction of the OEM vehicle floor was offered as part of an OEM model package. A floor of greater weight than the OEM floor which replicates OEM floor dimensions may be installed using materials of a heavier gauge/same material type than OEM construction materials.

GRILLE: The complete and specific OEM vehicle production grille must be retained in all vehicles. The impedance of air flow through production grille, including but not limited to the blocking of air flow in front of or behind the production grille, is prohibited. Any OEM device which permits the diversion of air flow to other areas is permitted.

HOOD: All vehicles must retain the complete and specific OEM vehicle hood and accompanying hardware including, but not limited to, latches, hinges, springs, brackets, braces and hydraulic assemblies. All OEM hood scoops, vents and openings must retain all accompanying hardware included in the OEM package. All hood liners, protective coverings, insulation and soundproofing materials may be removed. All hood scoops, vents and openings other than OEM designs are not permitted.

INTERIOR INSTRUMENTATION: All vehicles must retain the complete and specific OEM vehicle dashboard and its components including, but not limited to, analog and/or digital instrumentation, control buttons and knobs, window operation systems, duct vents and display screens. Heating/air-conditioning equipment may be removed but all interior environmental controls must be retained. All OEM interior collision apparatus, including but not limited to air bags, air bag deployment equipment and electronic collision-avoidance systems, may be removed. Any factory-deleted instrument panel, display screen or duct system area must be covered by panels to maintain the appearance of the specific OEM vehicle dashboard. Aftermarket instrumentation, including analog and/or digital gauges to monitor engine or vehicle systems, is permitted.

STREET EQUIPMENT: Emission controls and accompanying hardware may be removed. Windshield and backlight wiper blades, arms and motors may be removed. Heating systems, air conditioner systems and accompanying motors and hardware may be removed but interior controls must remain in the OEM positions. All OEM vehicle headlights, tail lights, brake lights and reverse lights must be retained and must be functional. All OEM interior lights and light panels, including dome lights and overhead lights, must be retained and must be functional.

WINDOWS: All windows, including windshield and backlight, must be clear except for those equipped with standard OEM tinted or photo-optic tinting safety glass. All OEM vehicle side windows may be replaced with Lexan® windows of the specific OEM side window dimensions. All OEM vehicle window operating systems must be retained and must be functional. All windows must be closed when the vehicle is in competition.

UPHOLSTERY: All vehicles must retain the complete and specific OEM vehicle interior upholstery including, but not limited to, carpet, door panels, headliner, and all seats. The OEM seat mounts may be secured to the OEM vehicle floor. The rear seat(s) may be removed when a roll cage or a roll bar is installed but the rear passenger area(s) must retain OEM carpet and upholstery or an accurate equivalent.



BALLAST: The addition of extra weight (ballast) to the verified OEM vehicle shipping weight may be required for eligibility. No more than five hundred (500) pounds of ballast, including the weight of any ballast containers, may be added to any specific OEM vehicle. All ballast installed to increase the weight of the OEM vehicle must be permanently mounted to the structure of the OEM vehicle and/or contained in an X-DRL-accepted ballast container. Affixing ballast to an OEM vehicle can be achieved by:

The addition of safety equipment including, but not limited to, a roll bar or roll cage, a transmission shield, and/or other safety devices.

The addition of a floor pan thicker than OEM vehicle specifications utilizing material of greater weight than OEM construction materials. The material thickness must be no greater than 18-gauge steel, (0.049 inches). The use of plate steel is not permitted.

The addition of a replacement trunk or cargo floor thicker than OEM vehicle specifications utilizing material of greater weight than OEM construction materials if the OEM production fuel tank is removed from the vehicle. The addition of extra chassis structure to reinforce existing OEM chassis components.

The addition of weight mounted permanently to the OEM vehicle frame attached by two (2 half-inch (0.500”) bolts for every one hundred (100) pounds of ballast with nuts welded to the bolts or one (1) three-eighths inch (0.375”) steel bolt for every five (5) pounds. All other weight attachment must use a minimum half-inch (0.500”) diameter SAE Grade 8 bolt. The addition of weight in a maximum of two (2) X-DRL-accepted ballast containers constructed of eighth-inch (0.125”) thickness material mounted securely to the OEM chassis with at least two (2) half-inch (0.500”) steel bolts. Each ballast container may contain no more than one hundred (100) pounds of ballast including the weight of the container. No ballast may be attached to the roll bar or roll cage. All ballast must be contained within the structure of the OEM vehicle and may not be visible outside the confines of the OEM vehicle body. No ballast may be mounted above the rear tires. All ballast must be secured to the OEM vehicle or enclosed in X-DRL-accepted weight containers. No liquid may be used as ballast with the exception of the fuel in the OEM fuel tank or contained within an X-DRL-accepted aftermarket fuel cell. All OEM turbocharger or supercharger intercooler tanks containing water and/or ice are exempt but all intercoolers must remain in the original and specific OEM location.

BATTERY: All vehicles must use a battery designed specifically for automotive use. The battery must remain in the original and specific OEM location and must be secured with original OEM equipment and hardware. A second battery designed specifically for automotive use is permitted and must be securely contained in the vehicle trunk or cargo area but away from any passenger area. The battery located in the trunk/cargo area must be enclosed in an X-DRL-accepted container constructed of polycarbonate material or enclosed in a container constructed from steel, (0.024 inches thickness), or aluminum (0.032 inches thickness). The battery container must utilize a vent system which directs all fumes outside the OEM vehicle body. The second battery must be secured to the OEM chassis or chassis structure with no less than two (2) bolts of a minimum three-eighths (0.375) inch in diameter. All vehicles utilizing a battery in the truck or cargo area must be equipped with an external Master Electrical Cutoff switch.

BRAKES: A braking system in the configuration of the complete and specific OEM vehicle production braking system must be retained on all four wheels in all vehicles. Aftermarket brake systems, including but not limited to replacement rotors, calipers, pads, master cylinders and brake lines, are permitted. The OEM emergency brake system may be removed if its removal does not interfere with OEM vehicle operation. The use of a front wheel locking system, (known as a Line-Loc®), is allowed if the system used is spring-loaded and automatically returns to the OEM vehicle’s conventional driving operation.

CHASSIS/FRAME: The complete and specific OEM production chassis/frame must be retained. Vehicles with OEM sub-frames may have sub-frames connected with material no larger than two (2) inches by three (3) inches by one-eighth (0.125) inch. Lateral (straight) connections between sub-frames may be achieved by using round tubing extending through the OEM vehicle floor to completely connect to the sub-frames.

DRIVER LOCATION: The complete and specific OEM production driver’s seat position and location must be retained and may not be altered or modified.

ENGINE MOUNTS:  All OEM vehicle engine mounts which include rubber sections may be replaced with steel engine height, angle and position in the OEM chassis. All vehicles must retain the complete and specific OEM engine plates and mid-mounting hardware.

GROUND CLEARANCE: A minimum of three 3” of ground clearance must be maintained from the leading edge of the OEM vehicle body and/or chassis to 12” behind centerline of front axle, 2” minimum for remainder of car.

ROLL BARS: An X-DRL-accepted Safety Roll Bar is required in all vehicles recording an elapsed time in the eighth- mile of 6.40 seconds or slower (7.00 seconds for convertibles). Construction guidelines and requirements for roll bar fabrication can be found in the Roll Bar and Roll Cage Specifications document.

ROLL CAGES: In all vehicles recording an elapsed time in the eighth-mile quicker than 6.40 seconds (7.00 seconds for convertibles), an X-DRL-accepted Safety Roll Cage is required. Unlike a Roll Bar which offers basic protection in the event of vehicle inversion or rollover, the Roll Cage must be built to offer multiple angles of driver protection. The Roll Cage structure provides extra protection by surrounding the driver with additional tubing. Construction guidelines and requirements for roll cage fabrication can be found in the Roll Bar and Roll Cage Specifications document.

SHOCK ABSORBERS: The complete and specific OEM production shock absorbers or Aftermarket replacementof OEM type utilizing OEM attachment point and style including, but not limited to,all hydraulic, pneumatic or electric units must be retained  and may not be altered or modified. Auxiliary reservoir are prohibited unless they are OEM production reservoir  units. All OEM production external shock absorber adjustment controls are permitted.

STEERING: Power-assist steering units and accompanying hardware may be removed and the vehicle may utilize a manual steering system.

SUSPENSION, Front: The complete and specific OEM production front suspension must be retained. Aftermarket tie-rods equipped with Heim joints are allowed. Sway bars may be removed.

SUSPENSION, Rear: The complete and specific OEM production rear suspension must be retained. Modifications to coil springs are permitted if the original mounting points remain unaltered. The upper control arm mounting point may be attached to the point of connection to the vehicle‘s rear end or differential. Solid bushings may be used in the rear suspension. The rear trailing arms may be replaced with X-DRL-accepted aftermarket units of OEM dimensions. Aftermarket lower units must be non-adjustable and have bushed ends or Heim joints. Aftermarket upper units may be adjustable and use Heim joints in place of bushings. Sway bars may be removed. Aftermarket or OEM torque arms are permitted only on vehicles which were originally produced with OEM torque arms and OEM production torque arm mounting points must be utilized.

TRACTION BARS: Aftermarket or OEM vehicle Traction Bars or Pinion Snubbers, (used to prevent differential rotation), are permitted. No shock absorber, spring, or other OEM vehicle suspension component may be relocated or altered to install the traction bar except those traction bars which are equipped with a new spring perch. Bolt-on traction devices are permitted if the front mounting point is not forward of the OEM control arm mounting position. The Traction Bar and/or its mounting hardware must not be lower than any part of the rear wheel. No traction devices, including but not limited to traction bars or ladder bars, may be welded to the vehicle chassis/frame.

TIRES, Front:  All front tires are limited to a maximum of a treaded tire accepted for highway use by the Departmentof Transportation (DOT) no greater in width and circumference than the exact specification of the tire originally supplied and delivered by the vehicle manufacturer with speed rating appropiate for vehicle performance and a minimum of a treaded tire which must have at least four and one-half (4.5) inches of tread width. Replacement of the OEM tire must be a tire designed for racing.

TIRES, Rear: All rear tires are limited to a treadless racing “slick” measuring no more than nine (9) inches in maximum width and no more than ninety-four (94) inches in maximum circumference designed for racing or a treaded tire accepted for highway use by the Department of Transportation (DOT) no greater in width and circumference than the exact specification of the tire originally supplied and delivered by the vehicle manufacturer. Alternate tires may be submitted to X-DRL Technical services Department for evualation and consideration for approval.

TIRES, All-Wheel-Drive: For vehicles equipped with OEM All-Wheel-Drive, DOT-accepted treaded tires no greater in width and circumference than the exact specification of the tire originally supplied and delivered by the vehicle manufacturer may be used in conjunction with the aforementioned racing “slicks” which must be mounted in pairs on the front or the rear of the vehicle. Racing “slicks” may not be used on all four wheels.

TIRES, All Vehicles: No portion of any tire may extend outside the fender wheel well opening. A maximum of three (3) inches of clearance is permitted from the tire sidewall to the nearest portion of the OEM vehicle body. All tires must be free of flaws. Any treaded tire must display a measured minimum tread depth of one-sixteenth (0.0625) inch. All vehicles using tires without inner tubes must be equipped with metal valve stems screwed into the wheel rim.

WEIGHT: All vehicles must meet minimum weight requirements determined by the OEM engine and OEM engine induction. All minimum weight requirements are subject to change at the sole discretion of the X-DRL Technical Services Department. Minimum weight requirements for other OEM engine and OEM engine induction combinations may be added at any time by the X-DRL Technical Services Department. All vehicles are weighed with the driver at the conclusion of an official qualifying or elimination round. The SCS minimum weights are:

3150 lbs: All vehicles using a naturally-aspirated V8 engine under 400 cubic inches

3250 lbs: All vehicles using a naturally-aspirated V8 engine over 399 cubic inches

3350 lbs: All vehicles using a naturally-aspirated engine with more than eight cylinders

3600 lbs: All vehicles using a supercharged or turbocharged engine

WHEELBASE: The complete and specific OEM production wheelbase dimensions must be retained with a maximum variance from OEM production specifications of no more than three-quarters (0.750) of an inch. Wheelbase dimension variations from side to side of the OEM vehicle may not exceed one (1) inch. No modifications or alterations are permitted to manipulate the wheelbase or the location of the wheels or axles.

WHEELIE BARS: Wheelie Bars in any configuration are prohibited on all vehicles.

WHEELS: Any OEM or aftermarket wheel is permitted. The diameter of each wheel must measure no less than Fourteen (14) inches  unless the wheel originally supplied and delivered by the vehicle manufacturer is smaller.



DRIVESHAFTS: The complete and specific OEM driveshaft(s) must be retained in all vehicles. All vehicles must be equipped with a full circumference driveshaft retaining device, (known as a “driveshaft loop”), enclosing each driveshaft. The driveshaft loop must be securely mounted to the chassis/frame no more than six (6) inches from the end nearest to the transmission of each driveshaft.

DRIVE UNITS/REAR END: The OEM rear end housing or drive unit may be replaced with any rear end housing or drive unit produced by the OEM for use in a passenger automobile. The width of the replacement rear end or drive unit may be increased or decreased to achieve the exact width of the OEM rear end or drive unit. The OEM width measurement between backing plates must be retained. Any gears which fit completely inside the OEM rear end housing or drive unit may be used to create any gear ratio. Limited-slip or ratchet-type rear ends or drive units are permitted. All OEM spring perches may be reinforced. Spool rear ends or drive units are permitted only when used in conjunction with aftermarket axles. Modifying or reinforcing the rear end housing or drive unit to increase strength and reliability is permitted. The OEM chassis/frame may be modified to facilitate clearance of the OEM driveshaft after OEM rear end or drive unit has been replaced. All OEM measurements between the OEM backing plates and the OEM vehicle wheelbase must be retained. The conversions of suspension components and/or shock absorbing systems to other than the original OEM vehicle configuration is prohibited. In any vehicle clocking an elapsed time quicker than 6.40 seconds in the eighth-mile, X-DRL-accepted aftermarket drive axles must be used.

TRACTION CONTROL: The complete and specific OEM production traction control system may be utilized. Electronic manipulation of the OEM traction control system is permitted.

TRANSMISSION, Automatic and Semi-Automatic: The OEM vehicle transmission may be replaced with any OEM transmission utilizing the same number of forward and reverse gears produced or offered by the OEM for use in a passenger automobile. An X-DRL-accepted plate to adapt the replacement transmission may be utilized.Modifications to the shifting patterns are permitted if  full shift patterns, including “Park” and “Reverse” selections, remain intact. The “Overdrive” gear selection and accompanying gear may be omitted. Gear changes must be a direct result of a driver action or a consequence of the transmission’s normal function induced by OEM vehicle hydraulic, pneumatic or electronic controls. Any aftermarket transmission fluid pan is permitted. Transmission tail shafts may be modified to permit tail shaft bushing replacements. All automatic transmissions must be equipped with a functional neutral safety switch. All vehicles utilizing an automatic or semi-automatic transmission must be equipped with a fully locking transmission fluid dipstick. In any vehicle clocking an elapsed time quicker than 6.40 seconds in the eighth-mile, an X-DRL-accepted flex plate meeting SFI Spec 29.1 and an X-DRL-accepted flex plate shield meeting SFI Spec 30.1 must be used. All transmission brakes are prohibited.

TRANSMISSION, Manual: The OEM vehicle transmission may be replaced with any X-DRL-accepted aftermarket transmission with the same number of forward and reverse gears produced or offered by the OEM for use in a passenger automobile. No OEM manual transmission may be modified or altered to operate as a clutchless transmission. The “Overdrive” gear selection and accompanying gear may be omitted. Gear changes must be a direct result of a driver action or a consequence of the transmission’s normal function induced by OEM vehicle hydraulic, pneumatic or electronic controls. All vehicles must be equipped with a steel flywheel shield meeting SFI Spec 6.1 or 9.1. The flywheel shield may not be modified for clutch adjustment access and/or ventilation. In any vehicle clocking an elapsed time quicker than 6.40 seconds in the eighth-mile, an X-DRL-accepted bell housing meeting SFI Spec 6.1/6.2 and an X-DRL-accepted clutch and flywheel assembly meeting SFI Spec 1.1/1.2 must be used.



AIR FILTRATION SYSTEMS/DUCTS: The complete and specific OEM production air filtration system, including all filtering elements, may be removed. All OEM air ducting may be removed.

CARBURETORS: The use of any carburetor or carburetors is prohibited.

CAMSHAFT/LIFTERS: All non-Helical OEM production camshafts may be replaced with X-DRL-accepted aftermarket camshafts. The original and specific OEM specifications of camshaft lift must be maintained as produced by the OEM for the specific engine configuration utilized. The camshaft lift specifications will be checked at the valve retainer at zero lash position. Replacement aftermarket lifters of OEM configuration are allowed. Aftermarket camshaft gear drives and/or camshaft drive belts are not permitted. Aftermarket timing covers are permitted if timing gears of complete and specific OEM production configuration are utilized. Hydraulic lifter camshafts will be inspected with the pushrod and rocker in place for normal operation and the solid lifter intact at zero lash position. Hydraulic lifters may not be plugged or set at an inoperative position. Adjustable pushrods or adjustable OEM production rocker arms are allowed but the total weight of the assembly may be no less than the specification weight of the OEM assembly. Pushrod guide plates are permitted.

CAMSHAFT, Helical: Helical camshafts may only be utilized in engines originally equipped with OEM Variable Valve Actuation (VVA) systems. The complete and specific OEM production Helical camshaft(s) must be retained. Modifications to any aspect of any Helical camshaft(s) is prohibited. Electronic manipulation of the VVA system, including alteration of the functions of the Helical camshaft(s), is permitted.

CONNECTING RODS: All OEM production connecting rods may be replaced with X-DRL-accepted aftermarket connecting rods. The total weight of the piston and connecting rod assembly, including but not limited to the piston, wrist pin, compression rings, and the connecting rod, may be no less than the specification weight of the OEM production piston and connecting rod assembly. Modifications to the connecting rod, including but not limited to weight removal or exterior polishing, are permitted on the beam of the connecting rod only. Modifications to increase the strength of the connecting rod are limited to the shot-peening method only. The length of the connecting rod must meet OEM production specifications with a variance of no more than twenty-five thousandths (0.025) of an inch as measured from the center of the wrist pin assembly to the center of the crankshaft journal. The size of the cylinder block bore or sleeve bore and the connecting rod bore housing must retain X-DRL-accepted OEM production dimensions.

CYLINDER HEADS: The complete and specific OEM production cylinder head must be retained and must retain its OEM appearance. All OEM production cylinder heads must carry the correct identification and/or casting number for the specific engine and chassis/frame application. All modifications or alterations to the OEM cylinder heads or combustion chambers, including but not limited to porting, polishing, welding, grinding, sandblasting and revising dimensions or airflow via material or chemical processes, are prohibited. All OEM cylinder heads must retain OEM production intake and exhaust valves with a variance of no more than one (1) degree from the OEM production intake and exhaust valve angles. All OEM production cylinder heads must retain the complete and specific OEM production cylinder head volume. The OEM production cylinder head port runners must retain the complete and specific OEM production cylinder head runner volume. No modifications are allowed to the OEM production cylinder head intake or exhaust runners. The OEM production cylinder head may be modified to provide clearance for pushrods with dimensions larger than the OEM pushrods. The addition of O-Rings to seal the cylinder head to the engine block is prohibited. The addition of exhaust plates is not permitted. Adapters for spark plugs are prohibited. All bolt holes for the valve covers must remain unaltered. All passages for heat risers may be blocked from the intake portion of the OEM production cylinder head but all valve pocket passages must remain open. The additions of PolyLock rocker arm nuts, low-profile “jam nuts”, BronzeWall valve guide liners, screw-in rocker arm stud upgrades and “Umbrella” valve spring and valve stem seals are permitted.

CYLINDER HEADS, Valves: All OEM production intake and/or exhaust valves may be replaced with X-DRL-accepted aftermarket intake and/or exhaust valves if the aftermarket valves are constructed of the same material as the OEM production intake or exhaust valve valves. The replacement intake and/or exhaust valves maintain must the OEM production dimensions of the valve head and valve stem in the valve guide area. The valve head diameter of any replacement intake and/or exhaust valve is permitted a variance of no more than five thousandths (0.005) of an inch more or fifteen thousandths (0.015) of an inch less from the valve head dimensions of the OEM production intake and/or exhaust valve. All OEM production variable valve timing (VVT) and variable valve actuation (VVA) systems are permitted if the complete and specific OEM VVT and/or VVA system is retained. Electronic manipulation of VVT and/or VVA systems is permitted. ENGINE: The complete and specific OEM production engine for the specific vehicle model claimed must be retained. The engine used in any vehicle must have a specific relation to the OEM body and chassis/frame in which it resides. Engines produced by an acknowledged OEM may not be used in a vehicle which is not a verifiable part of the same OEM corporate family of production vehicles. Aftermarket engine blocks retaining all OEM production engine specifications are permitted if the replacement engine block has been accepted for use by the X-DRL Technical Services Department. All engine equipment and accessories must be available through the OEM or an X-DRL-accepted partner of the OEM. The OEM production engine must remain in the specified location with no alterations to engine height, angle or position within the OEM chassis/frame. All engine cylinder bores may enlarged to a maximum of seventy-five thousandths (0.075) of an inch beyond the OEM engine specifications. Cylinder bore dimensions will be inspected and verified by measurements taken at the top of the cylinder bore where there is no evidence of wear caused by piston rings. All engines must retain the OEM production crankshaft. All engine rotating assemblies may be balanced to OEM specifications but must remain at the OEM production weight for the component or assembly. The distance of the connecting rod stroke is permitted a variance of no more than fifteen thousandths (0.015) of an inch from OEM production specifications. All OEM engine cylinder blocks may be equipped with steel cylinder sleeves. All engines must be equipped with a fully locking oil level dipstick. All vehicles clocking an eighth-mile elapsed time quicker than 6.40 seconds must be equipped with an aftermarket harmonic balancer meeting SFI Spec 18.1.

EXHAUST SYSTEM: A full and functional OEM production exhaust system is permitted but not required. All catalytic converters and emission control equipment and/or systems may be removed. Aftermarket exhaust headers are permitted but may not use adaptor plates, exhaust port plates or exhaust header plates. Crankcase evacuation systems are prohibited. FAN, ALTERNATOR, WATER PUMP: All vehicles must be equipped with a functioning alternator capable of powering all OEM production electrical equipment and accessories. Aftermarket alternators and/or aftermarket alternator pulleys are permitted. The alternator may be relocated from its OEM production mounted position. Aftermarket engine cooling fans and aftermarket electric cooling fan motors are permitted. Aftermarket water pumps are allowed but the aftermarket water pump must occupy the OEM production water pump mount without alteration. FUEL: All vehicles must use an X-DRL-accepted gasoline as fuel. Additives, including but not limited to propylene oxide, nitrous oxide, methyl alcohol, nitro methane and nitro methanol, are strictly prohibited.

FUEL SYSTEM: All OEM production fuel pumps may be replaced with one (1) X-DRL-accepted aftermarket mechanical fuel pump and/or one (1) X-DRL-accepted aftermarket electric fuel pump. All fuel pumps must be located outside of the vehicle passenger compartment and away from the vehicle suspension and tires. All electric fuel pumps must be operated by the vehicle ignition system switch. All components of the fuel system must be located more than six (6) inches from the vehicle firewall or engine bulkhead. All OEM production fuel lines may be replaced with metallic fuel lines of any size. Aftermarket rubber fuel lines not to exceed a combined total length of twelve (12) inches may be utilized in areas prone to vibrations. Fuel pressure gauge isolators must use steel-braided lines and may be mounted on the vehicle firewall. A maximum of one (1) container to externally cool liquid fuel is allowed.

FUEL TANK: Fuel may be carried onboard using the OEM production fuel tank or an X-DRL-accepted fuel cell. If the production fuel tank is used, the vehicle must retain the complete and specific OEM fuel tank and accompanying hardware including, but not limited to, OEM fuel inlet(s) and outlet(s) in the OEM locations. The OEM production fuel lines, fuel tank pickup and fuel tank pickup tube may be replaced with units delivering a greater capacity. The replacement X-DRL-accepted fuel cell must be no greater capacity than sixteen (16) U.S. gallons. If the replacement fuel cell is used, the OEM production fuel tank must be removed from the vehicle and a firewall bulkhead constructed of steel, (0.024 inches minimum thickness), or aluminum, (0.032 inches minimum thickness), must seal the passenger compartment from the fuel cell. If the OEM production fuel tank is removed from the floor of the trunk or cargo area, the vacant area may be replaced with material of at least the weight of the OEM production trunk or cargo area floor.

GASKETS: All OEM production engine cylinder head gaskets may be replaced with aftermarket cylinder head gaskets. Additional engine block deck clearance may be used to offset the use of a cylinder head gasket of less than OEM production thickness. A maximum of two (2) cylinder head gaskets of OEM thickness may be used.

INDUCTION SYSTEM, Fuel Injection: Any OEM fuel injection system(s) available on the specific OEM engine utilized are permitted including, but not limited to, Throttle Body Injection, (TBI), Central Fuel Injection (CFI), Central Port Injection (CPI), Multi-point Injection (MPI) and Direct Fuel Injection (DFI). The complete and specific OEM production induction system must be retained and may not be modified including, but not limited to, the throttle body, the plenum chamber and the intake manifold supplied with the complete and specific OEM induction system. Aftermarket electronic fuel injection systems are allowed if accepted by X-DRL Technical Services Department. Electronic manipulation of electronic fuel injection systems is permitted. Electronic Throttle Control systems (ETC or “Drive By Wire” systems) may be replaced by a mechanical throttle linkage. Fuel injectors of any size are permitted if installation of the larger fuel injectors can be achieved without modification to the intake manifold or engine cylinder head.

INDUCTION SYSTEM, Intake Manifold: The complete and specific OEM production intake manifold must be retained and must maintain its OEM appearance. All OEM production intake manifolds must carry the correct identification and/or casting number for the specific engine and chassis/frame application. All intake manifold modifications or alterations, including but not limited to porting, polishing, welding, grinding, sandblasting and revising dimensions or airflow via material or chemical processes, are prohibited.

INDUCTION SYSTEM, Supercharger: The complete and specific OEM production supercharger supplied with the complete and specific OEM production induction system must be retained for the vehicle model and engine utilized. No modifications of any kind are permitted. The supercharger inlet must remain in the OEM production location and position. Supercharger drive belts must retain the specific OEM model production configuration. All OEM production vehicles equipped with superchargers utilizing gear drive must retain the complete and specific OEM production supercharger supplied with the complete and specific OEM production induction system and must use the complete and specific OEM production gear set. The X-DRL Technical Services Department maintains a list of OEM superchargers originally offered for production vehicle use. Supercharger eligibility for the SCS is not guaranteed and constructors should consult with the X-DRL Technical Services Department prior to committing to a specific supercharger model. At present, the 4.0 liter, (244.20 cubic inches), displacement Ford Racing/Whipple unit is not eligible for SCS participation. All OEM production superchargers must be operated at OEM specifications of supercharger-to-crankshaft speed ratios including, but not limited to, rates of underdrive or overdrive. Aftermarket supercharger drive pulleys are not permitted. All OEM production superchargers must be equipped with rotors, vanes or impellers which utilize a helical rate no greater than the OEM helical rate of the rotors, vanes or impellers contained within the complete and specific OEM production supercharger. The injection of any liquid or gaseous substance into the supercharger housing, case or body is strictly prohibited. All OEM production supercharger intercooler tanks must remain in the original and specific OEM location.

All vehicles equipped with OEM production centrifugal superchargers must retain the complete and specific OEM production model supercharger casing, housing and impeller. No modifications are permitted to the supercharger casing, housing, impeller, supercharger compressor wheel, supercharger compressor wheel dimensions, centrifugal supercharger inlet port dimensions, discharge port dimensions, impeller inducer dimensions or impeller exducer dimensions. All vehicles equipped with OEM production positive displacement (Roots) superchargers must retain the complete and specific OEM production model supercharger casing, housing and rotors/vanes. The rotation direction of the supercharger rotors/vanes must be consistent with the complete and specific OEM production model supercharger. No modifications are permitted to the supercharger casing, housing, rotors/vanes, inlet port dimensions or discharge port dimensions. All vehicles equipped with OEM production positive displacement screw compressor superchargers must retain the complete and specific OEM production model supercharger casing, housing and rotors/vanes/screws. The rotation direction of the supercharger rotors/vanes/screws must be consistent with the complete and specific OEM production model supercharger. No modifications are permitted to the supercharger casing, housing, rotors/vanes/screws, inlet port dimensions or discharge port dimensions.

INDUCTION SYSTEM, Turbocharger(s): The complete and specific OEM production turbocharger(s) supplied with the complete and specific OEM production induction system must be retained for the vehicle model and engine utilized. No modifications of any kind are permitted. The turbocharger inlet(s) must remain in the OEM production location and position. The X-DRL Technical Services Department maintains a list of OEM turbochargers originally offered for production vehicle use. Turbocharger eligibility for the SCS is not guaranteed and constructors should consult with the X-DRL Technical Services Department prior to committing to a specific turbocharger model. The injection of any liquid or gaseous substance into the housing, case or body of any turbocharger(s) is strictly prohibited. All vehicles equipped with OEM production turbocharger(s), (defined as a centrifugal compressor powered by a turbine driven by engine exhaust gases), must retain the complete and specific OEM production model turbocharger casing, impeller/diffuser/volute housing, and compressor wheel/impeller/turbine. The rotation direction of the turbocharger compressor wheel/impeller/turbine must be consistent with the complete and specific OEM production model turbocharger(s). No modifications are permitted to the turbocharger casing, housing, turbocharger compressor wheel/impeller/turbine, turbocharger compressor wheel/impeller/turbine dimensions, turbocharger compressor wheel/impeller/turbine inlet port dimensions, turbocharger compressor wheel/impeller/turbine discharge port dimensions, impeller inducer dimensions or impeller exducer dimensions. All turbocharger Compressor Bypass Valves (CBV), (also known as “blow-off” valves or “pop-off” valves), are considered to be an integral component of the intake system and may not be physically modified or altered. The OEM production values at which the CBV is activated must be retained. Modifications to the OEM production turbocharger waste gate size and/or location are not permitted. Physical alterations to the OEM production Variable Geometry Turbine (VGT) system(s) are prohibited. Electronic manipulation of turbocharger systems is permitted. All OEM production turbocharger intercooler tanks must remain in the original and specific OEM location.

IGNITION: All ignition systems utilizing the general characteristics of the OEM production ignition system are permitted. The number of ignition coils must remain consistent with OEM production engine specifications. Electronic manipulation of the ignition system is permitted.

OIL PAN: The OEM production oil pan may be replaced with an X-DRL-accepted aftermarket oil pan. The addition of windage trays and/or baffles is allowed. No modifications to the general configuration of the oil pan are permitted. Alterations to the OEM chassis/frame for oil pan access are permitted but any material removed in the alteration must be replaced with permanent or removable material which does not compromise the integrity of the OEM chassis/frame.

OIL PUMP: The OEM production oil pump may be replaced with any X-DRL-accepted aftermarket oil pump if mounting in the OEM production location requires no modification. The OEM production oil pump, replacement oil pump, oil pump drive, OEM oil lines and complete oiling system must remain in the OEM production location. Vehicles equipped with an OEM production dry sump lubrication system must retain the complete and specific OEM production dry sump system.

PISTONS: All OEM production pistons may be replaced with aftermarket forged or cast pistons if the replacement pistons retain the specific OEM production piston design and configuration. No piston may create a compression ratio which exceeds the OEM compression ratio of the complete and specific OEM production engine for the specific vehicle model claimed. No pistons may be altered or modified in any way including, but not limited to, reconfiguration to the piston dome, dish, valve, piston ring, deck height relation or general engine cylinder location. Each replacement piston must display the exact design, configuration and dimensions of the OEM production piston. The total weight of each replacement piston assembly must be no less than the weight of the OEM production piston assembly. Replacement steel piston wrist pins are permitted but the replacement pin must retain the diameter of the OEM production pin. Pistons may be balanced to OEM production specifications. The drilling of holes in any piston for the purpose of manipulating cylinder pressure, (known as “gas porting”), is strictly prohibited. Any piston may be installed without regard for the manufacturer’s “arrow” directional stamp.

RADIATOR: The complete and specific OEM production radiator cooling system may be replaced with any X-DRL-accepted aftermarket unit. Radiator must be installed in the original location. All vehicles must be equipped with an X-DRL-accepted liquid overflow containment system.

ROCKER ARMS: All OEM production rocker arms may be replaced with X-DRL-accepted aftermarket rocker arms if the aftermarket rocker arm retains the exact specifications of the OEM production rocker arm. The use of adjustable OEM production rocker arms or the use of adjustable pushrods are allowed but adjustable OEM production rocker arms cannot be used in conjunction with adjustable pushrods unless the combination of both was offered by the OEM. Roller rocker arms are permitted only if roller rocker arms were available with the specific OEM production engine.

SPARK PLUGS: All engines are allowed the use of any spark plug designed for automotive applications. All engines are allowed the use of any ignition wiring designed for automotive applications.

STARTER: Any OEM production starters may be replaced with an X-DRL-accepted aftermarket starter if the replacement starter remains in the OEM production starter location.

THROTTLE LINKAGE AND CONTROLS: A progressive and/or mechanical throttle linkage is allowed. Electronic Throttle Control systems (ETC or “Drive By Wire” systems) may be replaced with a mechanical throttle linkage. Special X-DRL-accepted hand-operated throttle controls are permitted for competitors facing specific physical challenges.

TORQUE STRAP: A torque strap, designed to connect the engine to the chassis/frame during acceleration, is allowed but may only be connected to one side of the engine.

VALVE COVERS: Any OEM production or aftermarket valve cover is permitted if installation requires no modification to the engine cylinder head.

VALVE SPRINGS: All vehicles are permitted to use any valve spring if installation requires no modification to the engine cylinder head. Valve spring cups, which provide a stable seat for the valve spring, are permitted if installation requires no modification to the engine cylinder head. Steel valve spring retainers are mandatory.


HELMET: All drivers must wear a helmet meeting the rating specification of Snell M2005, M2010, K2005, SA2005, SA2010, SFI 31.2A, or 41.2A. In any vehicle clocking an elapsed time quicker than 6.40 seconds in the eighth-mile, the driver must wear a full-faced helmet meeting the rating specification of Snell M2005, M2010, K2005, SA2005, SA2010, SFI Spec. 31.2A, or 41.2A.

MASTER ELECTRICAL CUTOFF: All vehicles utilizing a main or secondary battery in the truck/cargo area must be equipped with an external Master Electrical Cutoff plunger contact switch capable of disrupting all electrical functions throughout the vehicle. The Master Electrical Cutoff switch must be conspicuously located on the outside of the rear of the vehicle and must be clearly and legibly labeled “PUSH OFF”.

NECK COLLAR: In any vehicle clocking an elapsed time quicker than 6.40 seconds in the eighth-mile, the driver must wear a neck collar meeting SFI Spec 3.3 or an X-DRL-accepted head and neck restraint device.

PROTECTIVE CLOTHING: Drivers must wear a fire resistant jacket meeting SFI Spec 3.2A/1, full length pants, socks and closed shoes in any vehicle clocking an elapsed time in the eighth-mile of 6.40 seconds or slower. In all vehicles recording an elapsed time quicker than 6.40 seconds, drivers must wear a fire-resistant jacket and pants meeting SFI Spec 3.2A/5 and SFI Spec 3.3/1 gloves. Open-toe and/or open-heel shoes or sandals prohibited.

ROLL BAR AND ROLL CAGE PADDING: All Roll Bars and Roll Cages must be covered with SFI Spec 45.1 spec padding in any area where the driver’s helmet can make contact while the driver is seated in the OEM vehicle driving position.

SAFETY BELTS: All vehicles must be equipped with a quick-release Driver Restraint System meeting SFI Spec 16.1 utilizing main belts no less than three (3) inches in width and a crotch belt ne less than two (2) inches in width. A quick-release Driver Restraint System meeting SFI Spec 16.5 may also be used. The Driver Restraint System must include legible labels which certify compliance with SFI Spec 16.1 or SFI Spec 16.5. The Driver Restraint System must include legible labels of the date of manufacture affixed by the manufacturer. The seat belts must be securely attached to the vehicle chassis/frame or a reinforced mounting to align all mountings to the direction of pull. The seat belts may not be wrapped around any chassis bars or rails. Cast steel mountings or U-bolt mounts may be used to secure the seat belts. Flat steel plates of no less than one quarter (0.250) inch thickness may be used for seat belt mounting if the plates have been relieved of sharp or ragged edges which may compromise the integrity of the seat belts. In vehicles without steel floors, a fabricated cross member constructed of two (2) inch by two (2) inch square tubing (of no less than 0.083 inches wall thickness), must be added for accepted seat belt mounting. Any penetration of the seat belt webbing is strictly prohibited.

WINDOW NET: In any vehicle clocking an elapsed time quicker than 6.40 seconds in the eighth-mile, a ribbon or mesh window net meeting SFI Spec 27.1 must be securely mounted on the inside of the Roll Cage with a permanent attachment at the bottom of the net. All attachment points must be designed to protect the driver and avoid contact with the racetrack surface or the racetrack retaining wall. Any penetration of the net webbing, except as performed by manufacturer, is strictly prohibited. Any modifications to the net may only be performed by the specific net manufacturer.



BURNOUTS: Burnouts or test launches over the starting line are permitted prior to staging for a qualifying or elimination round.

COMPUTER: The OEM production vehicle onboard computer may be replaced with an X-DRL-accepted aftermarket computer. Onboard data recorders are permitted.

CREDENTIALS: All competitors must possess proof of a valid X-DRL membership at all times. Any driver clocking an elapsed time quicker than 6.40 seconds in the eighth-mile must possess a valid X-DRL, NHRA, or IHRA competition license to compete. Valid IHRA and NHRA competition licenses may be transferred when presented with a current physical. Any driver clocking an elapsed time slower than 6.40 seconds in the eighth-mile must possess a valid and current driver’s license issued by the competitor’s state of residence or the United States government. All competitors must be at least eighteen (18) years of age.

LAUNCH CONTROL DEVICES: Engine RPM launch controls (“Two-Step” or “Rev Limiter” controllers) are permitted but must be activated by the driver’s foot via the brake pedal, the clutch pedal or a pressure switch. The movement of any vehicle may not be initiated by hand unless prior consent is given to permit special X-DRL-accepted hand-operated throttle controls for competitors facing specific physical challenges.

QUALIFYING AND ELIMINATIONS PROCEDURES: The eight (8) quickest qualifiers, determined by elapsed time after a maximum of four (4) qualifying sessions, will compete on a Sportsman Elimination Ladder schedule utilizing a four-tenths of a second (0.400) “Pro Tree” starting system. All qualifying and elimination rounds will be contested in a distance of one-eighth of a mile, (660 feet). Racing will be conducted without handicap starts or performance limits. The Sportsman Elimination Ladder will pit the Number 1 qualifier against the Number 5 qualifier, the Number 2 qualifier against the Number 6 qualifier, the Number 3 qualifier against the Number 7 qualifier and the Number 4 qualifier against the Number 8 qualifier. The act of “Deep Staging” is permitted. All competitors must immediately report to the staging lanes when requested for qualifying or elimination rounds or face possible disqualification. All qualifying and elimination rounds will be conducted under the existing rules of the X-DRL which dictate all violations and disqualifications. If a qualified competitor cannot report for the first round of eliminations, the quickest nonqualified, based on elapsed time after the conclusion of all qualifying sessions, will be inserted in the qualified field as an alternate competitor for the first round of eliminations and the alternate will assume the qualified position of the competitor unable to appear for eliminations. If any winning competitor is unable to compete in any subsequent round of eliminations, the driver recording the quickest losing elapsed time in the previous round of eliminations will be reinstated for the next round of eliminations in the position of the vehicle unable to compete provided the losing driver did not commit a foul start, boundary infraction or technical infraction. If more than one winning competitor is unable to compete in any subsequent round of eliminations, losing drivers will be inserted in the open positions on the basis of quickest elapsed time, (in order), without committing an infraction followed by losing drivers who committed an infraction on the basis of quickest elapsed time, (in order).

TOW VEHICLES: Tow vehicles are prohibited.