• Kyle Fella

3.0 Smooth Bore Diesel 4x4 Truck

Updated: Jan 19

1. Maximum weight 8000lbs.

2. The OEM chassis is mandatory. The vehicle must retain the full OEM chassis.

Wheel tubs, back- half conversions, tube chassis are prohibited. Maximum wheelbase

158” and 102” maximum width (outside tire to outside tire.) Rigid suspension

allowed. Hydraulic steering is allowed.

3. The body must be an OEM truck body, including the complete OEM floor pan and

must retain complete OEM firewall. Complete bed floor, hitch is allowed to protrude

thru the bed floor w/minimum amount of floor removed. No flatbeds permitted. The

body must retain the full sheet metal, aftermarket steel hoods are permitted. The

hood must be closed and securely latched while hooked to the sled.

4. Maximum engine size will be 460 cubic inch. Engines must come from factory in

one ton or smaller diesel pickup truck. Engine must remain in stock location as

intended by manufacturer. Engines may be interchanged between manufacturers.

a. No aftermarket blocks permitted

b. Head must be OEM or OEM one piece cast replica for that brand engine. No billet

heads of any material. Outside dimensions of cylinder head must measure factory

width and length. Head must retain OEM valve angle.

5. Front of engine block can be no farther forward than 17” of center line of front


6. Engine must have cable surrounding block and head. Cable must be minimum 3/8”

diameter located between cylinders #1 and #2. Cable must pass thru manifolds.

Cable will have 4-6” of slack with a minimum of 4 cable clamps at splice.

7. All engines will have a deflection shield, running the complete length of the block

casting. Shield must be securely fastened and must be .060” thick. (This equates to a

steel inner fender)

8. Hook point must be no closer than 44” of center line of rear axle, hitch height

maximum of 26”, with a minimum of a 3.75” X 3.0” opening. Hitch point must be

easily accessed. No “trick” type hitches permitted. Hitch must be stationary in all

directions. Hitch must be frame mounted. Hitch must be mounted center line of rear

hook point. No hitch supports or adjusters fastened to the rear axle housing shall be

above the centerline of the rear axle. Pivot pin of drawbar can be no farther forward

than center line of the rear axle.

9. Secondary hitch required. Minimum of 3/8” steel, located 12” below primary hitch

on the same vertical plane. (You should be able to look directly through both

at the same time – they need to be lined up.)

10. The turbocharger is smooth faced intake housing, limited to a maximum of 3.0”

inlet, (no map ring) with all air entering through the 3.0” opening. Intake wheel must

protrude 1/8th inch inside of opening.

11. Exhaust must exit straight up, with (2) 3/8” bolts mounted in a cross pattern no

more than 1” apart as close to the turbine wheel as possible, no more than 6” away

from turbine wheel.

12. Intercoolers allowed. Dumping or draining intercoolers without a catch pan

within 100 feet of competition track is prohibited.

13. Water injection is prohibited. All components must be removed from the truck.

14. Air shut off must have a cable that goes to the rear of truck operated by the sled

operator and also one to the cab of the truck. Kill switch will be securely mounted to

the back of the vehicle and have a two (2) inch diameter metallic ring to attach the


15. Fuel Systems: Maximum of one P7100 pump, limited to one plunger per cylinder.

The use of multiple high pressure common rail fuel pumps is allowed. Ford

Powerstroke engine may utilize a second HPOP. Electronic fuel injection is permitted.

A 3-way dump valve mounted before the injection pump is mandatory which can be

operated by the driver while strapped in the seat.

16. No fuel lines or tanks permitted inside of truck cab unless securely mounted in

marine box.

17. Fuel limited to diesel fuel. No alcohol, nitrous, propane or any oxygen enhancing

agents allowed.

18. Must run DOT approved tire. Maximum tire height 35”, no studded tires or

chains. No alteration to DOT tires allowed. Dual rear wheels are permitted on rear

axle only. Maximum of 6 tires.

19. Front weights must be no more than 60” from the center line of the front axle to

forward most point and be securely fastened. No weights are allowed in cab of the

truck. If weights are located in the bed of truck they are to be securely fastened to

the bed of the truck.

20. Drive train will consist of the following: Any front axle, any transfer case and any

rear axle. No planetaries permitted.

21. Axle shields are required. Shield to be .060” thickness steel or aluminum. Shield

not to be mounted to axle ends or hub bolts. A hole may be cut in one to allow

locking in of hubs.

22. No cast iron clutches or flywheels permitted, must be SFI approved. Trucks with

automatic transmissions, refer to General Rules.

23. SFI bellhousing blankets and/or SFI blow proof bellhousing required.

24. All U-joints must be shielded 360 degrees with 3/8” thick aluminum w/1/8” steel

liner or 5/16” thick steel. Shield will be 6 inches long minimum and centered on u-

joint. Inside diameter of shield will be no more than 2 inches larger than u-joint.

25. All intermediate shafts between the transmission and transfer case will be totally

enclosed in 3/8” aluminum or 5/16” steel, 1⁄4” of shaft may be visible.

26. Fire extinguisher (2.5#) or fire suppression system, Helmets-Snell 90 or better, SFI

fire suits, head sock, gloves, shoes, and seatbelts required.

27. All other rules may be found in 4X4 Truck and General Rule sections.

New for 2020


Drawbar height adjustment link if attached to rear differential housing the attaching point must be at axle centerline or below.

The drawbar adjusters cannot attach to anything above centerline of the rear axle. The adjusters must go down from drawbar. The adjusters can only go straight downward vertically or towards rear differential housing. No slotting of holes for adjuster attachment.


Must have a full metallic cab floor pan.

Update #2

The OEM chassis is mandatory. The vehicle must retain a full ¾ or 1-ton size chassis. Wheel tubs, back-half conversions, tube chassis prohibited. Maximum wheelbase 158” and 102” maximum width. (outside tire to outside tire). Rigid suspension allowed. Hydraulic steering permitted. (Intent= no Isuzu or compact diesel chassis)

Add –

No traction control permitted.


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