Hot Rod Big Block Tractors

WEIGHT: 6500 #

TIRES: 18.4 x 38 maximum, radials or bias.

AGE OF DRIVERS: 16 years or older, under 18 years must have parental consent.

SHEET METAL: Any sheet metal is allowed. Must be stock appearing in dimensions. Must be in stock location as original and measured from center line of the rear axle. Fenders are required, but do not have to match the sheet metal on the tractor. Fenders can be fabricated.

TRACTOR WHEELBASE: Wheelbase may not exceed 102″ from center of rear axle to center of front spindles. All front axles must be wide, narrow front ends are not permitted. Front wheels must overlap rear tires when sighted from front of tractor. Steering may be rack and pinion or hydraulic.

REAR END & TRANSMISSION: Rear end can be an agriculture tractor type, or a planetary with a truck center section. Internal modification to the stock transmission will be allowed. Bell housing and transmission may be removed if they were designed to be unbolted from the rear end at the factory. After market SCS and Profab type transmissions will be allowed. No differential locks are permitted in the rear end. No automatic or power shift transmissions. No TA’s are permitted. Universal joints, couples and shafts must be surrounded by (1/4) steel the entire length.

ENGINE: Engine must be naturally aspirated V-8, with a cubic inch displacement no larger than

521.16 cubic inch with a 1% variance. Block and heads must be cast iron. Single carburetor, no fuel injection, no turbo chargers or forced air induction of any kind. No tunnel ram, no sheet metal aluminum intakes, no casted sheet metal type, and no welded manifolds allowed. Only off the shelf after- market aluminum manifolds are permitted. Headers must exit in an upward direction. Motor must be parallel with input shaft of transmission and be mounted in the center of the frame. Spark plug guards must be in place to deflect downward or contain spark plug. No crank driven engine cooling fans, only electrically driven fans will be permitted. Crank harmonic dampener hub must be SFI 18.1 rated. Throttle must be dead man type with return spring. Air cleaners must be under the hood. Diesel conversions are allowed but must run on gasoline with no injection.

FRAME RAILS: Front end and frame rails can be fabricated but must be safe for the heaviest weight class. If frame rails do not extend to the rear end, ladder bars are mandatory and will be required and must extend ahead of the rear most mounting location of the engine block back to

the rear end. Maximum overall length, including weights measured from center of rear axle is 12 feet. Tractors with cast iron tub frames will have to be reinforced with steel. These tractors will be Grandfathered in and wm have two years from April 1, 2021 to replace cast iron frame with steel rails.

RPMS: Maximum allowable RPMS will be 7200. No more than 50 RPM variation over 7200. All ignitions must use an MSD box with a 7200 maximum RPM limiter chip or limiter box. No switches or dial operated devices that can control RPMS from the driver’s seat of the tractor is allowed. MSD boxes must be easily accessible for officials to tech. Boxes may not be tampered with or modified. Rivets must be original. If you drill a rivet out, you will have to buy a new box. If factory sealant or sticker is broken, a new box is mandatory. Only the wiring per MSD’s wiring diagram is allowed and must be plainly visible. No other wires may be attached to any of the MSD factory wires other than as specified per MSD’s wiring diagram. Tech inspections performed by using MSD model 89952 RPM Module/Chip Tester, MSD Model 8998 Digital Ignition Tester, and/or Datalog Peak Performance Recorder P/N -2347. All tractors must have a Datalog RPM PLUG KIT P/N – 3316. All wires from the Datalog RPM KIT P/N 3316 to the Datalog Peak Performance Recorder P/N 2347 will have to be exposed for Tech inspections at the bottom of one of the frame rails, from the harmonic balancer to the Datalog Peak Performance Recorder located on the pulling sled. These wires can only be spliced with connectors near the magnetic pickup on the front of the motor, in order to remove the engine. No other cuts, splices or connectors to the wires are permitted going back to the Datalog Peak Performance Recorder on the sled from the Datalog Magnetic Pickup on the harmonic balancer.

KILL SWITCH: Breakaway type kill switch is required and must be wired to the MSD BOX or ignition switch and the fuel pump. Switch must be accessible and functional. Subject to random inspections.

COMPUTERS: No computers allowed that control any mechanical operation of the competing vehicle. No automated or computer operation of traction control devices. The use of electronic control for ignition timing i.e. (MSD 8973, Power Grid, Six Shooter, MSD Digital, and Davis Electronics) is not allowed. (Wiring of any components Tach, Coil and MSD Box must be readily visible for inspection.) The use of Data Loggers and Map Censors are not permitted. All engines must be controlled directly by the driver through a manual throttle.

FUEL: Gasoline fuels only with a Maximum of 750 specific gravity, no alcohol, no pressurized fuels, no nitrous oxide, no oxygenated fuel, no nitrogen methanol, and no propylene oxide.

BELL HOUSING: Bell housing, fly wheel, clutch, and pressure plate must be SFI rated competition design with SFI rating of 6.1, 6.2, 6.3. Must have bell housing, no blankets are allowed.

DRAW BAR: Drawbars must not exceed 20 inches in height or less then 18 inches from center of axle to hooking point. No part of drawbar is to be attached to any point higher than the center of rear axle. Drawbar must be stationary in all directions. No clevis, absolutely no turnbuckles.

SAFTY EQUIPMENT: Roll bars or cages are required. Roll-over protection must extend higher than the drivers’ helmet. Five-point seat harness, helmet and fire suit, fire extinguisher, wheelie bars, front skid bars, and neutral safety start switch are required.

  1. When starting engines, operator must be in the seat. Starting engines while standing on the ground is prohibited. Unattended tractors with engines running are prohibited. These rules apply to the pit area, staging area, and track.
  2. All pullers will have two (2) attempts to start the sled. If the puller tries to stop their tractor before the sled passes a pre-marked spot, usually 75 to 100 feet from the starting line point on their first attempt, they may have a second attempt. The puller may also adjust their tractor at that time, including moving weights.
  3. All rules will be interpreted by Class Officials. The Class Officials will rule on any unforeseen problems or oversights with their ruling being final. Penalties for illegal pullers and /or vehicles will range from a friendly warning to a one year and ten-day suspension.
  4. Drivers must always stay on the seat of the tractor. Hands must be on the steering wheel, or throttle at all times.
  5. Any part falling off the tractor after being hooked and until the tractor is unhooked, could result in disqualification. Further, if any part of a tractor would fall off in the first 100 feet of a pull and the driver would want to stop and re-hook, “it’s still a disqualification,” you cannot hook again.

TECHNICAL INSPECTIONS: All tractors must be pumped for cubic inch and two oil pan bolts sealed with a wire seal before any tractor can pull in competition. Tractors already checked for cubic inch by Full Pull Productions (USA EAST) with a sealed oil pan can pull. Any tractor that has had its sealed oil pan wire removed will have to be pumped again. When performing the pump test, engine cubic inch can be a maximum of 521.16. A 1% variance will be permitted.

Protest Procedure: There will be no tear downs to check cubic inch. All cubic inch will be checked with the pump only. Protest fee for pumping for cubic inch will be $500.00. Protest fee for removing a carburetor will be $250.00. If the protest is sustained, the protest fee, will be returned to the protesting member. If the protest is not sustained, the fee, will forfeited to the protested member. When protesting another tractor, there will to be a form filled out and signed by the Protesting Member stating his protest. The Tech Official will have this form. Protesting Member will also present cash money when the form is turned in to the Head Tech, or one of the Committee Members. This procedure must be done within thirty (30)’minutes after the Hot Rod Big Block Tractors have finished pulling.


COMMITTEE. Tech Officials and/or tech people have the right to check and look at anything on a tractor at any time to ensure that the rules are being enforced and the tractor is safe for

competition. The only exception is for Protest, (checking cubic inch and carburetor removal, then Protest Procedure will apply.).


RULES LOCKED IN: All rules for the Hot Rod Big Block Tractors will be locked in for a period of five

(5) years from the start of the 2021season with the exception for safety. Any rule changes in the future, approved by the Big Block Tractor Member’s would also have to be voted on and approved by the Board of the Central Ohio Tractor Pullers Assoc-iation.

Membership: You must be a paid-up member to pull at any Central Ohio Tractor Pullers Association Event. Only one vote for per member for any rule changes or any other business associated with COTPA.

COMMITTEE CHAIRPERSON: Dean Kibler 330-831-3022

COMMITTEE MEMBERS: John Pitts, Les Pitts, Mike Yusko

TECH MAN: Kevin McIntire 330-428-4572