Top Dragster Rules
Wednesday, January 30, 2008




Class is for dragster and open bodied altered-type vehicles only.  Altereds must have open front wheels; no full fender and/or running board equipped street roadsters or funny car bodies permitted.  Qualified fields with competition conducted in a dial-in E.T. format.



TD followed by car number. Numbers must be at least four inches high.


Weight Breaks: *


Supercharged or turbocharged big-block altered: 2,000 pounds

Naturally aspirated big-block altered: 1,800 pounds

Supercharged or turbocharged big-block dragster: 1,800 pounds

NOS big-block dragster: 1,700 pounds

Naturally aspirated big-block dragster 1,600 pounds

Supercharged or turbocharged small-block altered: 1,700 pounds

Supercharged or turbocharged small-block dragster: 1,650 pounds

NOS small-block: 1,550 pounds

Naturally-aspirated small-block: 1,500 pounds

Naturally-aspirated 4 or 6 cylinder: 1,400 pounds


* Divisions 6 and 7 minimum weight for all entries 1350 pounds.


Refer to the current NHRA Rulebook and/or rules revisions for additional vehicle/driver requirements, specifications, and general regulations.  Any cars running quicker than 6.00 seconds must meet all comparable requirements for TAD or TAFC.






Carburetors, fuel injection or electronic fuel injection permitted. Two return springs mandatory. Throttle stops prohibited.



Any internal combustion reciprocating automotive engine permitted; any modification to engine acceptable. Four-valves per cylinder maximum. Engine may be in any location in dragster; front engine only in altered.  Harmonic balancer meeting SFI Spec 18.1 mandatory.


Engine-containment System

All cars must utilize an NHRA-accepted lower engine oil-retention device; may use a belly pan in lieu of a device attached to the engine. The belly pan must extend from frame rail to frame rail and extend forward of the harmonic balancer and rearward to the rear motor plate and must incorporate a minimum 2-inch-high lip on all sides. A nonflammable, oil-absorbent liner mandatory inside of retention device. See General Regulations 1:8.


Exhaust System

Competition exhaust systems permitted. Exhaust must be directed out of the car body to the rear, away from driver and fuel tank. If zoomies are utilized must be turned upward minimum three degrees.



NHRA-accepted racing gasoline, gasoline, alcohol, gasohol, ethanol, permitted. Nitromethane and propylene oxide prohibited.


Fuel System

Fuel lines must be isolated from driver compartment with a sub-floor or with steel-braided lines where the engine is located in the rear and the fuel tank is in front of the driver. No part of the fuel system may be mounted on firewall or in flywheel/flex plate area. All entries must have sufficient tank capacity to make full runs; adding of fuel after the engine has started is prohibited. All fuel tanks must be equipped with a positive locking screw-on cap and vented to outside of body.


Liquid Overflow

Catch-can mandatory for coolant overflow; one-pint (16-ounce) minimum capacity.


Nitrous Oxide

Permitted on non-supercharged or non-turbocharged entries only.


Oil Lines

All flexible-pressure oil lines, excluding return lines and any line 30psi or lower in pressure, must pass a minimum 300psi test for 30 seconds with no indications of separation, weeping, leaking, etc.  Competitors may test and tag their own lines.  Label must indicate date, PSI, and tester ID; label must be impervious to fuel and brake-clean.  All lines on supercharged alcohol cars must be routed in such a way that they are not directly in line with cylinder head gaskets at the front, rear, or side of the cylinder heads. 



All entries must be self-starting with an onboard starter and battery.



All supercharged entries may utilize a 14-71 (or smaller) standard or hi-helix supercharger. Screw supercharger prohibited. All front engine cars must have a SFI 14.2 or 14.3 Supercharger Restraint with approved bag from same manufacturer with the restraint straps and bag covered with fire resistant material. Rear engine cars must have a SFI 14.1, 14.2 or 14.3 Supercharger Restraint. Belt guards shielding both fuel and oil lines are mandatory. The blower restraint straps and fuel lines must be installed such that when the restraint straps are fully extended no load is placed on any of the fuel lines. Aluminum studs (supercharger-to-manifold) mandatory. All supercharged dragsters must utilize a torque converter assisted transmission.  See General Regulations 1:10, 1:11.


Throttle Stop

The use of throttle stops, stutter boxes, etc., to control down track engine rpm is prohibited. Throttle stops are defined as being mechanical, electronic or pneumatic. Throttle stop may be present on vehicle but must be disconnected from all controls.



The use of single or dual turbochargers is permitted.  This combination will compete at the supercharged weight minimums.


Valve Covers

Cast or fabricated metal valve covers, using all attachment bolt holes, mandatory on supercharged or turbocharged cars.


Vent Tube/Breathers

Mandatory for all supercharged engines. Two one-inch diameter connections. All breathers must be positive locking.



Clutch, Flywheel, Flywheel Shield

Flywheel and clutch meeting SFI Spec 1.1, 1.2, 1.3, 1.4, or 1.5 mandatory. Flywheel shield meeting SFI 6.1, 6.2, or 6.3 mandatory on clutch equipped cars. Engine combination determines the appropriate specifications. See the appropriate SFI specification or NHRA General Regulations for the motor plate and bolting requirements.



Each end of driveshaft must have round 360-degree driveshaft loops within 6 inches of U-joints.



Automatic transmission flexplate meeting SFI Spec 29.1 mandatory.


Flexplate Shield

Flex plate shield meeting SFI Spec 30.1 mandatory. A SFI 6.1 bell housing is permitted on torque converter assisted planetary transmissions.


Rear End

Aftermarket axles and axle-retention devices mandatory. Welded spider gears prohibited. Wheel studs must be 5/8-inch minimum. Aftermarket full-floating or live axle assembly mandatory on any vehicle that runs 5.99 and quicker or 240 mph and faster. Independent rear suspension prohibited.



Clutchless transmissions are limited to five forward gears; aftermarket planetary limited to three forward gears.  All vehicles must employ positive system to disengage from final drive. All automatic transmissions must have a neutral safety start switch and reverse lockout device. All supercharged dragsters must utilize converter-equipped units. All pressurized units must utilize flexible hoses pressure tested to 300psi and be clearly labeled as passing the testing process or solid steel lines and AN fittings to connect with accessory coolers. A minimum 1/8-inch pipe connection using high-pressure line vent to overflow tank (minimum 1-pint capacity) is mandatory.


Transmission Shield

A one-piece transmission shield meeting SFI Spec 4.1 is mandatory on all automatic and planetary transmissions.




Minimum of two rear-wheel hydraulic brakes required. Hand brake, if used, must be located inside the car's body or driver's compartment. Steel brake lines mandatory. All brake lines passing the engine on any rear-engine car must be shielded; recommended in all cars.


Pinion Support

Mandatory that all entries have a rear axle and/or pinion housing anti-rotation device of a rigid design attached directly from the frame or suitable cross member to either the rear axle housing or pinion housing in a manner to prevent rotation in either direction for unsuspended rear ends.



A device must be used to prevent steering shaft from injuring driver in case of frontal impact. Shaft must attach to steering box via a positive locking device; i.e. no rolled/pressed pins. If removable steering wheel is used, commercially available quick-disconnect steering-wheel adapter meeting SFI Spec 42.1 is mandatory.



Any automotive suspension permitted. Rigid-mounted rear axles permitted. Rigid-mount front axles permitted if wheelbase is 120 inches or more. A device must be utilized that will protect the oil pan from coming in contact with the racing surface in case of excessive frame flex and/or tire or wheel failure. Any front suspension using a beam or tubular axle must have the radius rods attached to the frame. Radius rods not required on front axles that are rigidly mounted 18 inches or less from the kingpin.


Wheelie Bars

Permitted. Wheels must be non-metallic.




Permitted, 250 pounds maximum, 100 pounds maximum removable.



Must have NHRA serialized sticker affixed to frame for applicable ET before participation. Rear-engine dragster must conform to SFI Spec 2.1, 2.3M, 2.5B, or 2.7B. Front-engine dragster must conform to SFI Spec 2.2B, 2.4B, or 2.6. Altereds must conform to SFI Spec 10.1E, 10.2, or 10.3. All side steer altereds must meet the requirements of SFI 10.4 for applicable ET prior to competition.



Mandatory.  Must meet SFI Spec 45.1.  See General Regulations 4:11.


Deflector Plate

Mandatory on rear engine cars. Must be installed between roll cage and engine on all rear-engine cars to protect driver. Minimum material thickness: .125-inch aluminum or .060-inch steel.


Ground Clearance

Minimum three inches required from the front of the car to 12 inches behind axle centerline, 2 inches for remainder of car except oil pan and exhaust headers.



Required. Cars running in excess of 200 mph must use dual parachutes with two separate shroud line mounting points using sleeved 1/2-inch bolts. Safety pins must be red-flagged and removed prior to burnout.



Rear-engine dragster minimum 150 inches, maximum 300 inches. Front-engine dragster minimum 150 inches, maximum 300 inches. Altered minimum 120 inches and maximum 150 inches. Maximum wheelbase variation from left to right: 2 inches.




Minimum diameter of 13 inches on front tires.



Automotive-type wire wheels permitted on dragster front axle only, provided total car weight does not exceed 1,800 pounds, excluding driver. Front-wheel fairings prohibited. SFI Spec 15.1 rear wheels with beadlocks or liners mandatory on any vehicle that runs 6.50 and quicker or 210 mph and faster.




Mandatory if metallic seat is used. See General Regulations 6:2.




A positive-locking device must be used to prevent accidental movements. Side-mounted canard-type units are permitted. No part of canards/wings may be within 6 inches of rear tire. A rear wing is mandatory on all cars that exceed 200 mph; minimum area 360 square inches, maximum 750 square inches, minimum height 55 inches (measured vertically from tailing edge to ground). Spill plates must be flat/straight and parallel and measure a minimum of 50 square inches each. Leading edge of wing may be no more than 10-inches forward of the centerline of the rear axle. Wing may not be configured or installed so as to generate negative downforce or lift. Any adjustment or movement during run prohibited.



Body and cowl may be constructed of metal, fiberglass, or carbon fiber and must extend forward to firewall. Altered entries must use a reproduction pre-1949 roadster or pre-1949 open (front) wheeled NHRA- accepted body (i.e. 1936-48 Fiat, Volkswagen etc. with roof exit). Full fender and/or running board equipped street roadsters and funny cars prohibited. May be converted to center-steer. Driver compartment, frame structure, roll bars, and body must be designed to prevent driver's body or limbs from contact with wheels, tires, exhaust system, or track surface. If driver's body is in contact with belly pan, a cross member and sub-floor are mandatory. Front overhang maximum 30 inches from forward most spindle center.



Mandatory.  See General Regulations 7:7.




Must have battery on board and permanently mounted in place for completion of run. Maximum two.  See General Regulatons 8:1.


Delay Box/Devices

Permitted. Two-step accepted for starting-line use. Down track throttle stops, electronic ignition interrupters (stutter boxes), or use of pneumatics are prohibited. Pneumatic starting line enhancers are permitted for all applications.


One delay box/device is permitted; it may be attached to the transbrake, and/or shift timer only. The wire to the transbrake (or line-loc) may contain a splice that activates the two-step/launch-control device in the ignition system. All wiring associated with the delay device, ignition system, automatic shifter, tachometer, data recorder, and fuel-injection system must be fully visible, labeled, and traceable. Delay devices and associated components (such as transbrakes, automatic shifters, data recorders, tachometers, fuel-injection system, etc.) must be utilized in an unaltered manner consistent with the manufacturer’s installation and instruction books unless otherwise approved. Any ignition system tachometer function or any other RPM function is prohibited from interaction with the delay device on any car that uses a pneumatic starting line enhancer.  See General Regulations 8:2.



After market electronic ignition boxes must be used unaltered from factory specifications. Timed ignition-interruption devices (stutter boxes) prohibited. Starting-line and/or “high-side” rev limiters permitted. Two-steps, rev limiters, or any other rpm-limiting devices, legal unto themselves but altered or installed so as to function as a down track rpm controller, prohibited. The wire to the transbrake (or line-loc) may contain a splice that activates the two-step/launch-control device in the ignition system. For supercharged and turbocharged applications also see the Delay Box/Devices paragraph above. The use of any programmable multi-point rev limiter and/or a rate of acceleration rpm limiter, either by themselves (i.e. MSD 7561) or integrated into the ignition system (i.e. MSD 7531) are prohibited.


Master Cutoff

An external master electrical cutoff switch required. If the switch is the “push/pull” type “push” must be the action for shutting off the electrical system, “pull” to turn it on.  The off position must be clearly indicated on all cars.  See General Regulations 8:4.



One functional taillight mandatory. Flashing, blinking, or strobe lights prohibited.



Data Recorders

Permitted. Data recorders may be used to record functions of a vehicle so long as they do not activate any function on the vehicle. Data recorders may not be activated by the throttle, clutch, brake, etc. Must be activated by a separate switch. Data may be reviewed (printout, replay, etc.) only after the run.  See General Regulations 9:1, 9:2.


Fire Extinguisher System

Mandatory on front-engine alcohol burning or supercharged/turbocharged gasoline burning cars and on any rear-engine car with enclosed cockpit, minimum 5-pound NHRA accepted system. All front-engine open-bodied supercharged/turbocharged alcohol burning cars, minimum 20-pound NHRA accepted system. Safety pins must be red flagged. See General Regulations 9:10 for accepted agents.


Tow Vehicles

Golf car or three- or four-wheeled, Quadrunner/ATV-type tow vehicle permitted. Full-size tow vehicle prohibited.  See General Regulations 9:10.



Arm Restraints

Mandatory.  See General Regulations 10:3.



NHRA Competition license and NHRA Top Dragster number with appropriate (3A, 3B, 4A, or 4B) license code and NHRA membership required.



Any location permitted in compliance with General Regulations. Any car with no cross member above driver's leg must have a strap or device to prevent legs from projecting outside chassis.


Driver Restraint System

Three-inch driver restraint system meeting SFI Spec 16.1 mandatory. Restraint system must be covered with fire retardant material on all supercharged cars. Restraint system must be updated at two-year intervals from date of manufacture.



Required.  See General Regulations 10:6.



Full face helmet with shield (goggles prohibited) meeting Snell 98, 2000, 2005 or SFI Spec. 31.2A or 41.2A mandatory.  Drivers of all supercharged, turbocharged or nitrous oxide equipped cars must use a full face Snell SA 2000 or SA 2005 or SFI Spec 31.2A helmet with shield (goggles prohibited).


Neck Collar

A head and neck restraint device/system is mandatory for any vehicle running 200 mph or faster. The device/system must meet SFI Spec 38.1 and must display a valid SFI label. The head and neck restraint device/system, when connected, must conform to the manufacturer's mounting instructions, and it must be configured, maintained, and used in accordance with the manufacturer's instructions.  Neck collar meeting SFI Spec 3.3 mandatory for all other cars.  A head and neck restraint device can be used with, or without, a neck collar. Modification of the device is prohibited.


Protective Clothing Requirements

Drivers are required to have as minimum requirements protective clothing labeled as meeting the following vehicle and engine combinations.


Any car with an automatic transmission in the driver compartment (no floor covering transmission):  Jacket and pants or suit meeting SFI Spec 3.2A/15, gloves meeting 3.3/5 and boots or shoes meeting SFI Spec 3.3/5 mandatory.


Front-engine, supercharged or turbocharged: Jacket and pants or suit meeting SFI Spec 3.2A/20, gloves meeting SFI Spec 3.3/15 and boots meeting SFI Spec 3.3/15 mandatory.


Front-engine with nitrous oxide or naturally aspirated using alcohol:  Jacket and pants meeting SFI Spec 3.2A/15, gloves meeting SFI Spec 3.3/5, and boots or shoes meeting SFI Spec 3.3/5 mandatory.


Rear-engine supercharged or turbocharged or equipped with nitrous oxide: Jacket and pants or suit meeting SFI Spec 3.2A/15 (SFI Spec 3.2A/5 jacket and pants or suit accepted until 5/1/2008), gloves meeting SFI Spec 3.3/5 and boots or shoes meeting SFI Spec 3.3/5 mandatory.


Naturally aspirated, i.e. all others: Jacket and pants or suit meeting SFI Spec 3.2A/5 and gloves meeting 3.3/5, and boots or shoes meeting SFI 3.3/5.


Head sock or skirted helmet required on all supercharged cars and all cars with an automatic transmission and/or converter in the driver’s compartment.  Head sock or skirted helmet also required on all open-bodied cars where a neck collar is not used; i.e. where a head and neck restraint only is used.




Qualified fields as designated by each division will be run based on the NHRA Sportsman ladder.  Divisions 2, 3, 4, 5 and 6 will qualify 32-car fields.  Divisions 1 and 7 will qualify 48-car fields.  Division qualifying rules are as follows:


Division 1:

         48-car qualified field w/minimum 7.70 qual. performance required.  Maximum dial-in .10 beyond slowest qualifying time, no slower than 7.70 (5.29 1/8 mile).

Divisions 2, 3, 4 & 5:

         32-car qualified field.  Maximum dial-in .10 beyond slowest qualifying time, no slower than 7.70.

Division 6:

         32-car qualified field.  Maximum dial-in .20 beyond individual qualifying time, no slower than 7.99.

Division 7:

         48-car qualified field.  Maximum dial-in .20 beyond individual qualifying time, no slower than 7.99.



A driver's best five finishes of the first eight NHRA Top Dragster races attended will count toward a division championship. At the time a driver enters a divisional event for the first time of the season, it is required that said driver declare which NHRA division is to be his or her home division. That division will become his or her home division for the season. Up to two "out-of-division" races may be counted. Once a driver has competed for points at the maximum number of eight Top Dragster events, the driver may compete at additional events but will not receive additional NHRA points. To be eligible for official NHRA Top Dragster points and subsequent postseason awards, a contestant must participate at a minimum of three races within his or her home division.


Points are awarded at all NHRA Top Dragster events as follows:



Field size

1st Rd.


2nd Rd.


3rd Rd.


4th Rd.


5th Rd.




4 or fewer








5 to 8








9 to 16








17 to 32








33 to 48









Additional points are awarded as follows for qualifying positions for racers claiming Division 1, 2, 3, 4 or 5 as their home division:









5th & 6th


7th & 8th


9th through 12th


13th through 16th





NORTHEAST DIVISION – NHRA Northeast Division Top Dragster Challenge

April 5 & 6                    Atco Raceway – Atco, N.J.

May 2-4                       Virginia Motorsports Park – Richmond, Va.

May 23-25                   Maple Grove Raceway – Reading, Pa.

July 4-6                        Lebanon Valley Dragway – West Lebanon, N.Y.

July 26 & 27                Numidia Dragway – Numidia, Pa.

Oct. 3-5                       Atco Raceway – Atco, N.J.

Oct. 24-26                   Maple Grove Raceway – Reading, Pa.


SOUTHEAST DIVISION – NHRA Hickory Motors Truck & Trailer Sales Top Dragster Series

Feb. 15-17                   Bradenton Motorsports Park – Bradenton, Fl.

Feb. 22-24                   Gainesville Raceway – Gainesville, Fl.

March 7-9                    Orlando Speed World Dragway – Orlando, Fl.

April 18-20                   South Georgia Motorsports Park – Cecil, Ga.

Oct. 3-5                       Atlanta Dragway – Atlanta, Ga.

Oct. 24-26                   Silver Dollar Raceway – Reynolds, Ga.


NORTH CENTRAL DIVISION – NHRA Spitzer Race Cars Top Dragster Series

April 11-13                   O’Reilly Raceway Park at Indianapolis – Indianapolis, Ind.

May 16-18                   Summit Motorsports Park – Norwalk, Ohio

June 13-15                  Route 66 Raceway – Chicago, Ill.

July 12 & 13                Mid-Michigan Motorplex – Stanton, Mich.

July 25-27                    National Trail Raceway – Columbus, Ohio

Aug. 22-24                   Beech Bend Raceway Park – Bowling Green, Ky.

Sept. 19-21                 National Trail Raceway – Columbus, Ohio



Feb. 15-17                   No Problem Raceway Park – Belle Rose, La.

March 7-9                    Memphis Motorsports Park – Memphis, Tenn.

April 4-6                       No Problem Raceway Park – Belle Rose, La.

April 11-13                   Texas Motorplex – Dallas, Texas

May 16-18                   Houston Raceway Park – Houston, Texas

Sept. 12-14                 Red River Raceway – Gilliam, La.

Oct. 17-19                   Thunder Valley Raceway Park – Nobile, Okla.


WEST CENTRAL DIVISION – NHRA West Central Top Dragster Series

April 25-27                   SRCA Dragstrip – Great Bend, Kan.

May 23-25                   Brainerd Int’l Raceway – Brainerd, Minn.

June 13-15                  Bandimere Speedway – Denver, Colo.

Aug. 1 & 2                   Cordova Dragway Park – Cordova, Ill.

Aug. 22 & 23               Heartland Park Topeka – Topeka, Kan.

Sept. 5-7                     Tri-State Raceway – Earlville, Iowa


NORTHWEST DIVISION – NHRA Northwest Top Dragster Series

April 25-27                   Firebird Raceway – Boise, Idaho

May 23-25                   Mission Raceway – Mission, B.C.

June 20-22                  Pacific Raceways – Seattle, Wash.

July 11-13                    Woodburn Dragstrip – Woodburn, Ore.

Aug. 15-17                   Yellowstone Dragstrip – Acton, Mont.

Sept. 26 & 27              Champion Raceway – Eagle Point, Ore.


PACIFIC DIVISION – NHRA Hughes Performance Top Dragster Series

Feb. 29-March 2          Firebird Int’l Raceway – Phoenix, Ariz.

March 7 & 8                 Southwestern Int’l Raceway – Tucson, Ariz.

May 2-4                       Auto Club Dragway at California Speedway – Fontana, Calif.

June 14-15                  Top Gun Raceway – Fallon, Nev.

Aug. 1-3                       Infineon Raceway – Sonoma, Calif.

Sept. 12 & 13              Auto Club Famoso Raceway – Bakersfield, Calif.

Oct. 3-5                       Auto Club Dragway at California Speedway – Fontana, Calif.

Nov. 6-9                       The Strip at Las Vegas Motor Speedway – Las Vegas, Nev.


Schedules subject to change.

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