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With the nostalgic look of early stock cars, Dwarf Cars are scaled copies of 1928 to 1948 vintage American coupes, sedans and trucks. They are powered by a motorcycle engine. The bodies are scaled down versions of full size cars.


The following are "COMMON SENSE" type rules. Our objective is to minimize rule changes. Do not attempt to build a Dwarf Car without first contacting a PHRA Board member for rule clarification. No exotic equipment, (meaning unusual or out of the ordinary). If a car is built that does not meet the Dwarf Car specifications, it will not be a Dwarf Car. Interpretations of or amendment to these rules may be made at anytime. The rules and/or regulations set forth herein are designed to provide for the orderly conduct of racing events and to establish minimum acceptable requirements for such events. These rules shall govern the conditions of all events, and by participating in these events, all licensees will be deemed to have complied with these rules. No express or implied warranty of safety shall result from publication of, or compliance with, these rules and/or regulations. They are intended as a guide for the conduct of the sport and are in no way a guarantee against injury or death to participants.
If it doesn’t say it in this rule book, you can't do it!


A. There will be no special class of cars; all oval track Dwarf Cars run under the same competition.

B. Car body will be of 1928 to 1948 vintage coupe, sedan, sedan delivery, wagon, or pick-up truck. Must have been a production car. All frames and roll cages, including firewall, doors, and rear section framing, must be fabricated as a single frame unit, already forming the actual contour and dimensions of the finished body. Sheet metal outside skins must be secured with Dzus type fasteners, or permanently attached by rivets or spot weld no more than 12" between each attachment point located at the perimeter of each panel where it meets the roll cage, firewall, or trunk framing. Skin must not bulge or gap open between attachment points. Any gap or hole exceeding 3/8" must be covered with sheet metal, a plug, or permanent type sealant.

C. No open top cars such as roadsters or convertibles. No convertible bodies with hard tops or "T" tops. The cars must be replicas of factory stock bodies. They must have full roof of metal construction. The roof shall start at the top of the cowl in the front of the car and extend, ending at the top of the trunk. Roofs must incorporate a front window. The windows must be cut to simulate to match the original body and shall extend inward to cover the roll cage in the front and the rear. All roll cage bracing must be intact, permanently welded. Enter and exit by door only. Doors must be functional and driver must be able to exit from either door safely.

D. No foreign makes. Only closed top, meaning hardtop American made passenger cars or trucks.

E .All cars will be of metal construction. No fiberglass, plastic, nylon etc. No aluminum for frame or roll cage. Outer skin shall be a minimum of 26 gauge steel or .030 aluminum. Firewall between engine and manned compartment is mandatory. There must be a complete firewall, front and rear separating engine and trunk compartments from manned compartments.

F. No fenders of any type. No structure of any type to simulate or act as a fender. Doors and windows must remain in stock appearance and location. Body must be skinned to match its type. (I.e. 3-window coupe must be skinned as a 3 window, not as a 5-window). Right and left doors must be operational and allow passage. Windows and door must be near scale size, shape and location. All doors must be hinged as to open.

H. Each car will have grill shell and simulated original grill matching it’s body style or a simulated radiator and vertical loop mounting bar mounted in near stock location and a hood to match radiator size and body style as not to distract from overall appearance. No grill is required if simulated radiator is used. Functional radiator may be mounted in the trunk area.

I. Engine compartment must conform to scale of body length and must match contour of body where it meets the right and left side of body panels. Firewall or cowling outer skin must be stock appearance in size and shape; only inner panel may be altered.

J. Any hood may be notched, bent or cut in such a manner as not to distract from the stock appearance or on car using a radiator/simulated radiator, hoods may not be altered so as to detract from neat appearance.

K. Hood scoop height ( ie: carbs, air cleaners, hood scoop) will be measured from a straight line projected out from the rear most portion of the hood. The maximum cowl height is 24" measured from the top of the frame rail to the top of the cowl. No part of hood scoop (ie: carbs, hood scoop, air cleaners) shall exceed 28". The hood scoop may not exceed 4" above that line and at no place on the hood may the hood scoop exceed 5". A tolerance of ½" will apply. There will be no obstruction of the drivers view.

L. At the beginning of race night, all cars must have all body parts intact.

M. No airfoils, wings or streamlining of body.


A. Maximum car height, 50", top to ground.

B. Maximum body width, 38". Measured from outside of door post to outside of door post on opposite side.

C. 40" maximum body height from bottom of frame rail to top of car.

D. The slope of the roof may not exceed 3 1/2" measured from the highest point in the rear just before the main cage starts to turn downward, to the lowest point just before the main cage starts to turn downward. The slope on the front hood should remain in proportion to the rest of the body.


A. Steel wheels only 13" wheel only. Use of Bead Lock rims is highly recommended on the right rear. Rim not to exceed 10” in width.

B. Department of Transportation approved tires, 50 duramoter or harder, and/or any hoosier tire or rc1,rc3,UDRA,medium or soft. Can be grooved in any manner. New rule adopted 11/09 reads as follows: Allowed to run any hoosier dwarf car tire, rc1, rc3, soft, medium, udra etc. As approved by the board. Chainlink or dirt boz block only is the intent.


A. Wheel base 73" (1" tolerance allowed) measured at the center of the spindle to the center of rear end housing.

B. Outside tire width not to exceed 62" (must be able to pass through 62" opening)


A. Alcohol or any type of gasoline is permitted.

B. No nitrous oxide, no nitro or propylene oxide type additives.


A. Not to exceed 5 gallons.

B. Tank must be vented so as not leak fuel in any position, non leaking cap. Must include a check valve.

C. Fuel cell must be mounted between frame rails, in trunk.

D. Fuel cell must be mounted with metal straps only.

E. Must have complete fire wall between driver and fuel cell.


A. Motorcycle engines only. No snowmobile or other special application engines. 1250cc is the maximum allowable displacement. Any questions about approved motors, please contact PHRA officials.

B. 1250 cc maximum, 4 cycle, 4 cylinders maximum.

C. Must be a regular production (minimum of 500 units per year).

D. Engine must have all original parts operational, such as transmission and clutch. Clutch and transmission must be in engine and clutch and all gears operational.

E. Charging system optional.

F. No turbochargers, blowers or forced induction .Must be naturally aspirated.

G. Engine must be cooled by original intent. May use extra fans or oil cooler.

H. Exhaust and headers must be installed so as not to detract from stock appearing hood, with the exception of side panels.

I. Muffler are mandatory, 95 dba @ 100'.

J. No auxiliary starter.

K. Fuel Injected Engines: All engine rules above apply plus. No aftermarket boxes allowed.


A. Must use drive shaft from motor to automotive rear end.

B. Driveline loops shall be 360 degree construction of 2" X 1/4" flat bar or 3/4" X .065 wall tubing, minimum. The front loop shall be within 8" of the center of the front u-joint. A second loop shall be within the knee/thigh area. A third loop is to be located in the bulkhead area. Three driveline loops are MANDATORY.

C. Drivelines must be painted white.

D. Quick change rear differentials are allowed.


A. Roll cage must be constructed of a minimum 1.25".065 wall OD or 1.5" OD x .065 wall tubing in the main roll cage. Secondary members will be a minimum of 1" OD x .065. wall.

B. All lower frame side rails will be a minimum of 1" x 2" rectangular tubing with a minimum of .120" wall. The lower frame rails on the right and left side running from the extreme front to extreme rear. Does not include cross member. If frame rail is cut, it must be gusseted with 1 x 2" .120 wall. No round, oval or square tubing in lower side frame rail. No over slung rear frame rails.

C. There will be a minimum of three (3) cross members in the main compartment; one at the forward end, one in the center and one at the rear. The cross members will be made of steel only, with a minimum wall thickness of .120". Cross members may be round, oval, square or angle.

D. The right and left doors must have a minimum of two bars with a minimum of.065" wall x 1" OD tubing welded through the midsection of the door frame. The bar supporting the drive shaft tunnel may be included as one of these, only on drive shaft side. Drive shaft side of car must have one bar, minimum of .065" wall x 1" tubing, welded inside to front and rear door post positioned horizontally.

E. All cars will have a permanent structure support bar, located behind the seat at shoulder level. The bottom of the seat will not be more than 63" back, measured from the upper ball joint to the center of the seat at the height of the permanent structure bar. The seat may be tilted back for added driver head clearance; however, no portion of the seat may be back more than 68" as measured above. A seat pan must be welded in place, using a minimum of 16 gauge steel.


A. All engines must be front mounted, in stock location for model of car.

B. Engines may not be extended more than 12" to either side of car body center line.

C. Engine set back is the square of the motor (rear fins) may not extend more than 17" from center of front axle. No part of the engine or transmission may be more than 21" set back, as measures above.


A. Front suspension must not exceed 25 inches measured from the ground to the highest point of any front suspension, or extend rearward past the most forward panel of the firewall, except under frame rail, where it can not be seen from either side.

B. Steering components must have safety fasteners, such as cotter pins or self locking nuts.

C. If steering box is mounted in front cowling, the pitman arm may not extend more than 1 ½ inches outside the natural contour of the body near that point, and must not prevent proper door operation.

D. No straight axles.

E. No leaf spring or torsion bars.

F. No bird cage type rear linkage or Jacob’s ladder.

G. Trailing arms, located outside the frame may not extend beyond the rear door post.


A. car must weigh 1,200 pounds with driver


It is the driver’s responsibility to ensure that their car is within the prevailing technical inspection at all times. It is the driver’s responsibility to ensure that their car will meet the minimum weight requirements when exiting the track after each event.

The Technical Committee may choose to weigh the cars after a race which would require any car and driver to report to the scales by virtue of their finishing position. Any driver who fails to exit the track and drive immediately and directly to the scales shall be disqualified. Any car weighing less than the minimum weight shall be disqualified. Disqualification due to a violation of the minimum weight rule will result in forfeiture of all points and prize monies earned at all events on that date and the car and driver will not be allowed to compete during any further competition on that day.

It is the sole responsibility of the driver to know their finishing position and their obligation to report to the scales. If any driver is uncertain of their finishing position, they should drive directly to the scales to ensure that they are not disqualified.

Only the PHRA technical inspection staff or their appointees, and the car drivers shall be permitted at the scales. Sportsman like conduct on the part of all drivers, pit persons, or car owners is required. The driver shall be held responsible for any unsportsmanlike like conduct of his or herself, their pit persons, or their car owner.

B. No ballast will be mounted outside of body or frame. All ballast must be securely bolted or welded inside of body or frame rail and extend no lower than frame rail. Ballast will be painted white and have the car number clearly marked.


A. Front bumper must be no wider than 36" and a minimum of 24" and will not extend more than 6" forward of front tires.

B. Rear bumper must be no wider than 50" and a minimum of 40" and will not extend more than 6" from extreme rear body panel or 8" if the car has a simulated fuel tank. Rear bumper may not extend past the rear tire tread.

C. Front and rear bumpers must be a minimum of 4" above the ground, and a maximum of 14". A 2" extension bar may be allowed on top of the bumper, but must not exceed 16" high from the ground.

D. Bumper will be a minimum of 6" wide vertically.

E. Bumpers are to be made from 1" round tubing .065" minimum, and .095" maximum wall.

F. There will be no sharp points or edges.

G. Nerf bars must be mounted on both sides in front of rear tire and be no more than 18" from center of rear axle to rear of nerf bar. A minimum of a three (3) point mounting is required. The lower bar must be parallel to lower frame rail from the rear of the car then curve or bend toward lower frame rail. The upper bar is to attach to the roll cage a maximum of 18" above the rear attachment point of the lower bar. An additional diagonal brace from frame rail to lower bar is strongly recommended. Nerf bars must not interfere with the opening of either door and must roll through a 62" opening.

H. These nerfs will be constructed of round tubing 065" x 1" OD, and a maximum of .095" x 1" OD wall tubing. Lower bars may not extend more than 1” past the tire tread in rear only. Must roll through 62" opening. Must roll through 62" opening.


A. All batteries must be rear mounted (trunk area). Batteries must be securely mounted with a top restraint made of metal. Restraint must also hold battery caps.

B. Cars should have master electrical switch clearly located and marked.

C. No electronic (i.e. computer) traction devices. No electronic or manual devices will be adjustable by the driver during a race. Any such devices shall be mounted outside the driver’s compartment.


A. DIRT: Must have at least three (3) brakes controlling 3 wheels. 1 per wheel. Electrical shutoff devices allowed on right front only(must have 4 working brakes to use). The only devices allowed within the reach of the driver is a mechanical brake bias valve and electric brake shut off valve.


A. All inside suspension mounts must be shrouded from drive compartment. No sharp edges or protruding objects which could endanger driver shall be inside driver’s compartment. All cut and free standing edges must be folded, molded or filed smooth (i.e. window and door edges).

B. All cars must have an approved 5 point racing harness, equipped with a quick release buckle. Both ends of harness must be attached to the frame of the car with, not less than 3/8" grade 8 bolts. All seat belts will be installed at a 45 degree angle to the driver’s hips. Shoulder harness comes from behind the driver, and will go over both shoulders so that they will be held securely in the seat. (All safety restraint harnesses will be installed in accordance with manufactures guidelines). PHRA highly recommends belt replacement or recertify every 2 years

C. Approved racing type helmet with current snell rating are to be used. (SA-2000).

D. All cars will have a production made quick-release, removable steering wheel.

E. All cars are required to have an on board fire system. Must be a minimum 5 lb. system with 2 nozzles installed. All pits must have a minimum of a 2 lbs. fire extinguisher accessible in their pits.

F. All drivers must wear an approved driving suit. Single layer fire suit is minimum.

G. All drivers must wear an approved neck brace and fire proof gloves. It is strongly recommended to use a head restraint device. These devices may become mandatory by the tracks in the future.

H. When racing on asphalt, a catch can for oil and water is required.

I. All door latches must be a positive locking device, so as not to open from vibration or up set, and not to jam if door is damaged. All hoods and trunks must be securely fastened by, spring latch, nuts and bolts or dzus fasteners (no screws)

J. No glass of any kind will be permitted a 1/2” mesh windscreen is required. A rock guard grill made of a minimum three (3)-1/4” steel rods evenly spaced across the windscreen opening, one centered and the other two evenly spaced and centered between the remaining openings. A rock guard grill with more than three (3) bars is highly recommended.

K. No listening or transmitting devices.

L. No rearview mirror of any type.

M. No radiator or oil cooler will be mounted in the driver’s compartment, or on the rear deck.


A. All cars must have numbers in five (5) locations: Numbers on right & left door and roof must be a minimum of 12" high, and the width must be 2/3 of the height, except for the number #1. On the roof, it should be as large as possible. The number on the rear of the car must be a minimum of 6", and located above the bumper so to be viewed by the driver behind. The assigned association letter must be a minimum of 6" high on the roof and the doors and 2" high on the rear of the car. A minimum 2" number and letter must be displayed on the left front upper corner of the windshield. All numbers must be permanent (ie: vinyl or painted). All numbers should be made to be as large and clear and plain as possible to assist in scoring.

B. No Roman numerals, or Gold leaf.

C. The issued assigned number must be used within twelve (12) months of issuance starting in February of the current season. Club membership must be current with P.H.R.A. Any number not used within a twelve month period automatically reverts back to the ownership of P.H.R.A.


The only device allowed within reach of the driver is a brake bias adjuster.

ThePacific Hardtop Racing Association has established its policy with regard to use of on-board computers on race cars competing pursuant to the PHRA Rulebook. Except those computers installed on stock motorcycles by the new vehicle manufacture for the proper operation of such vehicles, no vehicles may be equipped with computers which in any way effect the operation of the vehicle. All related wiring, sensors, etc., must be identifiable to the Tech Inspector. A computer is defined as any device (electrical, mechanical, pneumatic, hydraulic, etc.) that activates any function of, or in any way effects the operation of the vehicle based on measurement, sensing, processing, etc. of any Data related to the performance of the vehicle. Display or transmission of any data gathered or processed, to the driver or any remote location is strictly PROHIBITED!

Data recorders may be used to record functions of a vehicle, so long as they do not activate any function of the vehicle. Data recorders may not be activated by the throttle, clutch, brake, mechanical mechanisms, radio transmissions, sensing of wheel speed, inertia, laser device, or transmission of track position or location, must be activated by separate switch. Transmission of Data gathered or processed by Data Recorder, to the driver or any remote location is strictly PROHIBITED! Data (print out, replay, etc.) may only be reviewed at the completion of a Race, after the vehicle has stopped.