Rule a. replaced with: Bellhousing must be mounted as SFI certified by manufacturer with grade 8 studs or bolts that can be identified as grade 8. Socket head bolts allowed only for clearance problems.
Rules e and f. replaced with: Bellhousing must be mounted with grade 8 studs or bolts per manufacturer’s bolt pattern for motor and bellhousing. All bolts must be in place.
Rule i updated: Starting Jan 1, 2024 all SFI bellhousings regardless of material i.e. steel, titanium or aluminum must display a current SFI sticker with an expiration date affixed by the manufacture. The NTPA steel stamp will no longer be acceptable as a replacement for SFI decal after Jan 1, 2024.
Exhaust rule 7, pg. 33 and 34 – added Or, a billet steel cross/cage incorporated into the exhaust outlet supplied by the turbocharger manufacture. (Dimensions still in process)
P7100 Series Pump: For classes limited to maximum size injection pump of P7100 series, pump housing (main pump body) dimensions not to exceed 2-5/8” wide X 9-9/16” long X 8-3/16” tall. Limit one plunger per cylinder. No billet pump housings. Pump will be held to OEM centerline of fuel rack to top of housing and centerline of camshaft to top of housing and OEM plunger bore centerline.
Divisions limited to P7100 injection pump are: Light Pro Stock, Limited Pro Stock, Pro Farm, and Light Limited Super Stock.
P8600 Series Pump: For classes limited to maximum size injection pump of a P8600 series, pump housing (main pump body) dimensions not to exceed 3.175” wide X 10.475” long X 8.665” tall (+ or – .010”). Limit one plunger per cylinder. No billet pump housings.
Divisions limited to P8600 injection pump are: Super Farm and Hot Farm.
Injection pump required to be mounted in the stock location only in affect for Light Pro Stock Tractors which is no change to previous class rules.
All diesel fuel and diesel / bio blends will be measured using a dielectric meter only. A maximum reading of 13.4 / 150 based on which type of dielectric meter used.
Water and soluable oil (lubricant) mixture must measure plus or minus .2 using a water hydrometer or a maximum reading of 5 on a refractometer.
Light Unlimited deleted. Light Modified adopted and offered at SN/GN level.
Limited to two supercharged automotive type piston engines limited to 14/71 size supercharger with no overdrive limit, or may be turbocharged. No single engine tractors, no naturally aspirated engines or turbines. Weight limit is 6,000 lbs.
Maximum weight will remain 2050 lbs. Vehicle no longer required to have any moveable weight.
“New” Sled Bump Rule
a. Any competitor who breaks at the event site will receive hook points for all classes entered, but will not receive place points or any purse money unless there has been a measurable pull by that vehicle in that respective class except under circumstances covered in letter b.
b. Competitor is not required to bump sled if breakage occurs during first session of competition and not able to compete in second session for same class only. Place points issued only in class with 15 or less total entries including per hook, non-member entries. Rule does not apply if vehicle has not competed in first session of class that breakage occurred. Vehicle must make a measureable hook in first session in order to qualify for last place points in second session of same class. If vehicle has already competed and recorded a measureable distance in a different class previous to breakage and is entered in that same class in a later session, then vehicle will be awarded place points under same conditions in both classes.
Example: vehicle competes in UNL in session 1 making a measureable distance and then breaks during competition in MOD class in session 2. If vehicle is unable to compete further in that event, then vehicle would qualify for last place points in second session for both classes under criteria described previous.
First Pull Attempt
a. On first attempt, no matter where the vehicle stops prior to 100 foot, as long as competitor lets off the throttle prior to 100 ft. marker, no matter the circumstance causing (out of bounds, kill switch pulled, lost weight, roll over, etc.), competitor will get a second attempt. Even if vehicle travels beyond the 100 ft. marker, competitor will be allowed a second attempt as long as competitor let off the throttle prior to 100 ft. marker.
b. If no attempt is made to let off the throttle, no second attempt will be granted.
Note: Intent is for driver not to slam on brakes to stop before 100 ft. marker (or at any time), but to come to a smooth, safe stop.
c. All competitors, except “Test Puller”, will have the option to make a second attempt immediately or drop (6) positions after first attempt as long as competitor did not go past 100 feet. Competitor will have one attempt remaining. For “Test Puller” options, see Section…….
Pro Stock Tractors – RN level on trial basis in Region 2
Turbo limited to 5 inch intake and exhaust, no intercooler, all other rules for Pro Stock class in NTPA Rule Book remain the same as GN Heavy Pro Stock including cubic inch, component chassis and weight.
Super Stock FWD Trucks:
(this class will move from the back of the book to the front and be a regular RN class)
1. Super Stock FWD truck shall follow the NTPA Rulebook for Modified Four Wheel Drive except where superseded by rules found therein.
2. Maximum wheelbase of 133 inches for Super Stock FWD trucks. Must have OEM frame of a truck. All rear end housings must be fastened rigid to the frame. Front axle must be a Dana 70 or under automotive front.
3. Engine to remain in stock location as intended by manufacturer plus or minus 3 inches. Mini Truck (S-10, Ranger, Dakota, etc.) are permitted to run V-8 engines.
4. Front axle must remain in intended original location. Center of front or rear wheels cannot exceed plus or minus 2 inches of fender walls being used.
5. Engine must be the same manufacturer as the truck. Center to center bore spacing to be OEM stock on the engine (Ford 4.9, GM 4.84, and Mopar 4.8). Any cam allowed, and intake manifold changed permitted with one single, four-barrel carburetor with working floats and mechanical linkage. Not to exceed standard 4500 series dominator gasket. Engine must run on gasoline fuel only. Aluminum heads are permitted. No hemi or semi hemi style head. Heads must be cast and not billet. Fuel injection and/or air compressing devices are not permitted.
6. Engine block must be OEM stock steel or its replica, no aluminum engine blocks permitted.
7. Fuel samples and or fuel tests may be conducted at any time at the discretion of the competition director.
8. Hitches to be built to specifications in NTPA Modified FWD section. Hitch length to be a minimum of 30% of the wheelbase.
9. Maximum tire size is 35 inches tall by 12.5 inches wide or metric equivalent of 315/75. Must be a D.O.T. tire.
10. Can use aftermarket transmission and transfer case.
11. Any type of rear end may be used. (Military and or 2 ½ ton truck or automotive)
Note: Region 2 is limited to 410 cubic inches
Region 3 is limited to 530 cubic inches
Region 6 is limited to 500 cubic inches