Current nine-week season

Monday Night Racing
DTM Season

Official technical rules and car specifications for the current DTM season at Viper Pit Raceway.

Latest revisionAugust 17, 2026

At a glance

Quick Specifications

Use this summary for setup and tech inspection. The detailed rules below control if a question arises.

Chassis: 4-inch, two- or three-piece metal flexi
Motor: Chicagoland Stage 2 CR102 or Mid-America Road Runner
Gearing: 64 pitch · 14-tooth pinion / 35-tooth spur
Rear axle: 3/32-inch solid metal
Maximum width: 83 mm (approximately 3.26 inches)
Rear clearance: 0.047-inch minimum, including motor
Front clearance: 0.010-inch minimum at pan and center section
Body: DTM style · 0.007-inch minimum thickness unless specified

Complete requirements

Detailed Rules

Cars must comply with all specifications throughout competition.

01

Frame and Chassis

Use a commercially available 4-inch, two- or three-piece metal flexi frame.
Frame cutting is prohibited except for the small amount necessary at the pillow blocks to fit rear bearings, oilites, or bushings.
The motor may be soldered in place.
Motor braces and pin tubes are permitted.
Weight may be added as needed and must be attached to the top of the chassis.

02

Rear Axle

A 3/32-inch solid metal rear axle is required.
Exotic axle materials are prohibited.
Flatted axles are permitted.
Bushings, oilites, or ball bearings are permitted at the rear axle.

03

Dimensions and Clearance

Maximum overall width: 83 mm, or approximately 3.26 inches.
Minimum rear clearance: 0.047 inch, including the motor.
Minimum front pan and center-section clearance: 0.010 inch.
Measurements are taken with the complete car resting on a slotted tech plate.

04

Light Pans

Masters class may use any commercially available lightweight pan.
Pro class may use commercially available light pans produced by the same manufacturer.

05

Front Tires

Front tires are optional.
If used, front wheels may be 3/8 inch, 1/2 inch, or 5/8 inch.
Wing-car-style front wheels are not permitted.

06

Motor

Approved motors: Chicagoland Stage 2 CR102 or Mid-America Road Runner.
Motors must remain factory sealed and unopened.
Internal motor modifications are prohibited.
The motor shaft may be shortened.
The manufacturer’s permanent identifying etching must remain on the motor can.

07

Gearing

64-pitch gearing is required.
Use a 14-tooth pinion and 35-tooth spur gear.

08

Body

A DTM-style body is required.
Unless otherwise specified, minimum unpainted body thickness is 0.007 inch.
Aerodynamic-effect modifications and add-ons are prohibited.