PDTR Wingless Super Modified Rules  for 2015

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 In 2015 Transponders will be mandatory on all cars 

To start the 2015 season any engine will be allowed, any fuel. We may add weight and a harder tire for larger engines to equalize for 360 engine. After the division
has been established an engine rule will be written.

  1. Steel Frames

    1. Fabricated steel frames must meet these specifications: Thickness – to be no less than .120 inch; Frame rail width – must be two (2) inches; Frame rail height – must be no less than four (4) inches and 2X4X.120 inch TUBE STEEL ONLY.  Frame rails may be tapered from front roll cage upright to no less than two and one quarter (2-1/4) inches.  Length – frame rail must begin no more than nine (9) inches behind center line of front axle, and must be continuous to the rear of the fuel tank.  ALL FRAMES MUST BE APPROVED BY PDTR.

    2. Minimum width of the frame inside must be no less than twenty-six (26) inches between the frame rails. This measurement will be taken at the front vertical upright of the roll cage and continue all the way to the rear of the frame. This rule also applies to the lower rails of the chassis and must remain twenty-six (26) inches minimum width inside throughout the entire driver’s compartment.

    3. No round tubular frames of any manner, shape or form will be allowed.

    4. Minimum wheel base allowed will be ninety (90) inches measured from wheel center to wheel center on both sides.

  2. Steel Roll Cages

  1. Roll cages must have a six point mount with rear roll support mounted within eight (8) inches of the top of the roll cage and run rearward to main frame rail.  Front roll cage upright may be extended below belt line with square tubing.  All roll cage tubing must measure no less than one and three-quarter (1-3/4) inches O.D. and .095 inch wall thickness.  All right angles must be gusseted and properly welded.

  2. All roll cages must measure no less than twenty-six (26) inches inside at the top rear and no less than twenty-three (23) inches inside at the top front.

  3. Minimum side protection on both sides between bottom of window opening and floor or lower chassis rail must be two (2) vertical bars, equally spaced and two (2) horizontal bars equally spaced.  Side protection bars are to be a minimum one and one-half (1-1/2) inches O.D. and .095 wall thickness.

  4. Top and rear roll bars and bracing behind seat must be adequately padded in all areas where the driver’s head may contact.

  5. Roll cage must extend above driver’s helmet by a minimum of two (2) inches DIRECTLY ABOVE THE DRIVER’S NORMAL SEATED POSITION MEASURED FROM SIDE TO SIDE.  More clearance is recommended.  No roll cage extensions are allowed.  If there is not two (2) inches clearance above driver’s head, car will not be allowed on track.  Any additional bars or hoops above or around driver must be approved by PDTR.

  6. Side window opening height must be no less than seventeen (17) inches and no more than twenty-four (24) inches, measured from the bottom of the top roll cage bar to the top of the top horizontal side bar.

  1. Driver’s Compartment

    1.  High back aluminum or better seat is mandatory.  Seat must be securely bolted in a minimum of four (4) places; 2 in the bottom and 2 in the back of the seat with ¼ inch minimum diameter grade 8 bolts.  NO DZUS FASTENERS ALLOWED.

    2. All cars must have protective plating securely fastened to protect the rear half of the bottom of the seat and the lower portion of the vertical back of the seat.  Plating can be no less than one-eighth (1/8) inch thick steel or one-quarter (1/4) inch thick aluminum.

    3. Steering wheels must be quick-release type.  No plastic quick releases allowed.

    4. Steering gear box and tubes must be adequately padded to protect driver’s knees.

    5. All cars must have a complete firewall between the driver and the engine and a firewall between driver and fuel tank.  Rear firewall must extend to bottom of the fuel tank.  All cars must have complete floor boards or adequate length to protect driver’s feet.  All sheet metal must be no less than 22 gauge steel or .050 inch aluminum.

    6.  No rear view mirrors of any kind are allowed.

    7. Ignition switch must be mounted on the right side of the dash within reaching distance of the driver when securely strapped in, and clearly marked.

    8. Toe strap on top of accelerator pedal is mandatory


  2.  Bodies and Hoods

    1. Bodies must be identifiable to automobile manufactured bodies.  Suggest using replica or original tail-lights.  You may run topless or open top cars. If you run a roof NO WICKERBILL! PITCH FROM FRONT TO REAR of roof NO MORE THAN 2in.!

    2. Sprint type cars, midget, etc. do not maintain a stock car appearance and will not be allowed.

    3. No late model full bodied stock cars will be allowed to run as a modified.

    4. All cars must have a hood that extends over the top of the radiator.  Hoods must be straight front to rear, and may be rounded right to left.  Cowls and mud deflectors may be part of the hood.  No holes are allowed in top of hood.   All cars must have a 360 degree steel fan guard.

    5. Stainless steel screening is compulsory in windshield 2X2X3/16.  Left and right windows must have protective screen to deflect stone, etc.  No glass of any kind permitted.

    6. Numbers must be on both sides of the car and roof if used.


  3.  Mirrors – No rear view mirror will be allowed.

  4.  Engines

    1. Any American made V-8 cast iron block production engine 360 OR smaller may be used.  Stock type aftermarket replacement blocks may be used.  No aluminum block or heads allowed.  No Oldsmobile Rocket blocks allowed.  Ignition must be camshaft driven. No more than one (1) spark plug per cylinder and no more than two (2) valves per cylinder will be allowed.    Any engine not listed must be approved by PDTR. No titanium parts allowed anywhere on car except in valve train.

    2. Intake one piece, aluminum or cast iron. No high rise tunnel ram. Unaltered carburetor, fuel pump mechanical stock type diaphragm only, no piston pumps.  Carburetor heat spacer allowed, a maximum of 1/2 inch thick. Only one (1) air cleaner is allowed, 14” round and 4” tall.  No stack extensions on top of carburetor. If running engine bigger than 360 with fuel injection, we may add weight, harder tire, or increase tire pressure to make the car competitive to a 360 engine.

    3. Stock HEI Ignition ONLY!! NO MAGINETOS NO MSD BOXES!!!

    4.  All cars will use an adequate radiator overflow tank of at least one (1) quart capacity. It is not allowed to be mounted in the driver’s compartment. Overflow may be run through exhaust header as long as no water problems exist.

    5.   No dry sump oil systems will be allowed.

    6.  Exhaust must exit in front of rear tires, and below top horizontal side bar.  Mufflers and elbows must be welded on entirely approved by PDTR.  Cars will be routinely checked with a decimeter and those louder than 100 decibels will be required to modify their systems to lower the level of noise emissions. Muffler systems cannot be changed after decibel reading is taken.  Headers 1 5/8 in. OD, no merge collector.  One collector per side.  No tri Y Header collectors.  No slip connectors. Mufflers part # Schonfield 112535-112530 ONLY!!!

    7.  Engine Placement – The position of the engine is up to the discretion of the car builder, except; No rear engine or mid-engine cars will be allowed. Engine must be mounted between frame rails and driver must sit behind engine.

    8.    Traction control devices of any kind are illegal.

    9. NO super chargers, turbo chargers, nitrous oxide, or timed injection will be allowed.


  5.  Flywheels and Bell Housings

    1. Any type flywheel may be used and the car must be equipped to be self-starting.  All cars must be equipped with one working clutch.  The car must have a neutral gear.  Steel or aluminum drive flanges may be used. 

    2.   All cars must have a BLOW PROOF bell housing.

  6.  Transmissions

    1.  All cars must be equipped with a self-starting, self-propelled type transmission.  Must be able to move under own power to get car moving.  One forward gear and one neutral gear in transmission mandatory.  Driver must be able to shift gears while securely strapped in car.

      No shifter rear ends or shifter drive lines.  No quick change auxiliary or automatic transmissions allowed.  Transmission must be bolted to back of bell housing and must be mounted to outside of bell housing.  Dog type clutches can be run.

    2. All cars running an open drive shaft must have a complete loop of one-quarter (1/4) inch thick by one (1) inch wide steel attached to the frame to support the support the front end of the drive shaft.  An adequate safety chain, strap or other device must support torque arms.  Driver’s compartment must be shielded from open drive shafts.

    3. All open drive shafts must be painted white.

  7. Front Axle, Spindles, Hubs and Shocks

    1. Only steel front axles, king pins and spindles with standard length ¾ ton (Wide 5) spindle snouts will be allowed.  Only standard Wide 5 hubs allowed.  No billet hubs allowed.  Hubs must be interchangeable on all four spindles.  The right front hub does not need brake rotor mounts.

    2.  Welded steel shocks only with removable bearing or rubber ends, No shocks that are adjustable from the driver’s compartment allowed.  No mono-tube shocks allowed. No aluminum shocks allowed, No take apart shocks.  Coil over steel shocks allowed.  No Bilstein XVS series shocks allowed. ALL SCHOCKS MUST BE Approved By PDTR

  8.  Differentials

    1. No restrictions as to manufacturer. Quick change rear ends are allowed. Any car running a passenger car rear end must have conventional full-floating hubs. No open tube rear or aluminum axle tubes are allowed.

  9.  Brakes

    1.    All cars must have a minimum of three (3) wheel hydraulic brakes, one on each rear wheel. All in good working condition.

    2.  Steel brake rotors only; no aluminum or composite rotors or coated are allowed.

    3. Cars are allowed to run proportioning valves.

  10. Fuel and Fuel Tanks

    1.  Fuel tank must be mounted equal to or higher than the height of the top of the rear axle tubes, in the truck area of the car. No nylon straps allowed.

    2. Fuel cell only enclosed in a steel container, mounted in a safe manner approved by PDTR. [ See Speedway Motors fuel cells or equitant]

    3. If fuel line is run inside driver’s compartment, it must be steel braided line, Aeroquip® push lock line or a line of equivalent structure, or it must be contained inside steel tubing.

    4. Anti-surge fuel filler caps are mandatory.

    5. No form of pressurized fuel system will be allowed.

    6. All cars must have an easily accessible ball valve shutoff mounted inside frame rails at right rear of car

    7. The accelerator linkage must be equipped with two return springs in the linkage.

    8. Cable type accelerator linkage will be allowed if approved by PDTR.

  11. Bumpers and Nerf Bars

    1. Front bumpers must not extend beyond frame rails.  All corners and edges must be rounded.  Main bumper structure must be one and one-half (1-1/2) inch diameter round tubing.  Standards and cross bars must be at least one (1) inch round tubing.  All standards must be properly braced.  Standards must be connected by a horizontal cross bar parallel to the main bumper hoop.  Front bumper must not extend more than twelve (12) inches beyond the leading edge of the front tires.  Single hoop front bumpers will be allowed, but must be between fifteen (15) and twenty-one (21) inches from the ground.

    2. Rear bumper minimum width must be equal to outside width of frame rails, and maximum width no greater than rear tire tread width.  Main bumper structure must be of one and one-half (1-1/2) inch minimum diameter round tubing.  Maximum distance from the ground to the bottom of the rear bumper or standards cannot exceed fifteen (15) inches.  Minimum distance from the ground to the top of the rear bumper or standards can be no less than twenty-one (21) inches.  All vertical standards must be connected by horizontal cross bars no smaller than one (1) inch diameter round tubing.  All standards must be properly braced.  Rear bumper must have at least three (3) vertical standards with one in center line of frame.  Outside corners and edges must be rounded.  When bumper extends beyond the width of the frame rails, it must be looped back 180 degrees to the frame.

    3. Nerf bars must not extend beyond outside of tires.  Materials for nerf bars will be no less than one (1) inch diameter round tubing, and rounded on the edges and corners.

    4. All bumpers and nerf bars must be built of round tubing and painted or plated in a bright color.

  12. Wheels and Tires

    1.   Steel wheels only, fourteen (14) inches wide maximum, plus bead lock. Must be painted or plated a bright color.

    2. Tire pressure bleed-offs will not be allowed.

    3.  * Approved right rear tire for the racing season will be American Racer 33.0/13.0-15GT SD44 compound for cars that meet the engine rule. All other cars,
      American Racer 33.0/13.0-GT15 MD62 with adjusted tire pressure. This tire must measure 14” or less, from Point A to B, as illustrated below. The measurement will be taken on a 14” wheel with bead lock and the tire pressure set at 12 psi.  The tire must also have a durometer reading of 28, or harder with a surface temperature of 150 degrees.  Any tire that does not meet the guidelines in this section will not be legal regardless of the sidewall stamping.

    4.  Foam plugs, Aluminum or Lexan wheel covers safely attached approved by PDTR

  13.  Batteries

    1. All batteries must be safely and securely fastened between frame rails and between front and rear torsion bar tubes (or the equivalent on coil spring cars). Batteries must be protected from the driveshaft or other flying debris with 1/8 inch aluminum or 1/6 inch steel if mounted in the driver’s compartment; subject to the approval of PDTR. Standard acid type batteries must have the positive post and entire top covered to prevent acid spillage in the event of a roll over. Gel or dry cell type batteries must have the positive post covered.

  14.  Weight of Cars

    1. Minimum weight 2,150 cars that meet engine rule. All other cars weight will be adjusted according to engine size.  Cars will be weighted directly from the track, without pitting.  Any parts lost during a race may be used for weighing the car, with the exception of fluids and weights.

    2.  All weights must be painted white, identified with the car number, and securely fastened, subject to the approval PDTR.

    3. Loss of any weight on the track will result in a ten (10) point and money penalty.

    4. Weight will be established with PDTR Scales

  15. Driver’s Safety

    1. See Track Rules.

  16. Drives Must Be 16 Years Old

    Transponder will mounted on the left side rear tortion tubes.