Ladder Type: Sportsman

Field Size:       Up to 32 qualifying cars

Qualifying:     3 scheduled rounds for 1-day events, 4 rounds for 2-day events

Light Type:     0.400 Pro

Staging:          Courtesy Staging Encouraged, Deep Staging Allowed

Min. Qualifying Time:           12.49 seconds (12.99 sec. at Bandimere Raceway)


Class Summary

No turbo, no nitrous, no problem! The IDRC PRO-AM ALL-MOTOR class features the nation’s top unibody max-effort racecars. High-tech, four-cylinder, venerable air cooled and wild rotary engines are all welcome. We expect top performers to run low-to-mid 10s.

Eligible Platforms

Any import or domestic sport compact FWD or RWD platform is allowed. Engines may be an inline 4 or two-rotor rotary. Engine type and manufacturer will dictate minimum weights.


All vehicles must have functional taillights and at least one functional headlight. Fiberglass, fiber-reinforced plastic (FRP) and carbon- or aramid- (Kevlar®) fiber body panel replacements are allowed. One-piece front ends are not permitted. Both doors must be functional, with the ability to open the doors from the inside and outside of the vehicle.

Chassis and Suspension

“Full tube chassis,” “3/4 chassis” and “1/2 chassis” conversions are not permitted. Vehicle must remain unibody with all factory shock towers functional in the OEM location. Rear suspension must remain the same design as OEM. If the rear suspension was originally Independent Rear Suspension (IRS), it must remain IRS. Driver position must be in OEM location (i.e. no center-driver conversions permitted). Wheelie bars are not permitted.


No restrictions


OEM and IDRC approved 4-cylinder engines are allowed. Two-rotor rotary engines are also allowed. Currently, the DART B-series engine is the only approved non-OEM engine. Racers wishing to certify other non-OEM engine platforms must submit a request for approval to the IDRC technical department. Engine “swaps” are allowed, as long as the swap is from the same manufacturing group (i.e. Honda/Acura, Toyota/Scion/Lexus, Nissan/Infiniti, etc.). Billet engine blocks or cylinder heads are not permitted. Cast aftermarket cylinder heads are permitted. Engine location may be setback up to six inches from the original location. Engines MAY NOT run a dry sump oil system in this class. Engines may run only distilled water for coolant. Up to 16 ounces of surface-tension reducer (i.e. Royal Purple Purple Ice additive) per cooling system is permitted. No ethylene glycol or propylene glycol coolants are allowed.

Approved Fuels

Pump E85, E98, VP Racing C16, VP Racing Pro Import, VP Racing Q16, VP Racing C85. No propylene oxide or nitromethane is permitted.

Transmission and Axles

Open to OEM manual or OEM automatic transmissions only. Case may be upgraded to a billet version. Gearsets and internals can be upgraded to straight-cut and/or dog engagement H-pattern. No sequential conversions are allowed.

Fuel Cells

Aftermarket fuel tanks and fuel cells may be used as long as the factory location is maintained.


No restrictions.

Nitrous Oxide Systems

Not allowed.

Wheelie Bars

Not permitted.


FWD and RWD slicks limited to 25.0 inches in height and 8.0 inches in width.

Minimum Competition Weight


Minimum       Engine/

Weight                        Platform

1,900 lbs.       K-series Honda FWD

1,850 lbs.       H-series Honda FWD

1,850 lbs.       Non-specified 4-cylinder OHC engine

1,800 lbs.       B-series Honda FWD

1,750 lbs.       D-series Honda FWD

1,725 lbs.       Type-I Case RWD VW Air Cooled

1,675 lbs.       Non-Type-I Case RWD VW Air Cooled


All vehicles must weigh-in after a qualifying run to ensure that the minimum weight was not violated during the run. The vehicle must make its way to the scales under its own power or with an IDRC supervised tow. This eliminates the possibility of teams adding weight between the end of the run and scales.


All crewmembers accompanying the vehicle on track (up to three) must be in like uniforms. Uniforms can be as simple as matched t-shirts and jeans. All crewmembers must also sign the additional release waiver.


Class payouts will vary based on each event. However, larger fields will receive larger payouts. Fields smaller than eight vehicles will receive a pro-rated payout based on the number of qualified entries. Eight-vehicle fields will only payout winner and runner-up. Fields with 16 and 32 cars will also payout semifinalists.

IDRC West Coast Nationals & International Finals (1day event)

32-Car Field16-Car Field8-Car Field