PRO3 Rules & Specifications

PRO3 Guiding Principle

PRO3 is a spec racing class for BMW E30s in the Pacific Northwest. It is the intent of the PRO3 class to  create a restrictive formula for BMW cars designed to emphasize driver ability rather than design and preparation of the car. The spirit of the formula will not allow any modifications that would increase the cost of competition, nor lend to an unfair performance advantage.


Example Images of a PRO3 Build (Courtesy of Advanced Auto Fabrication)


Specifications (at a glance)

  • Body: 1987-1991 BMW E30 325i, 2-door or 4-door
  • Engine: Stock M20 6-cylinder (std. performance chip allowed)
  • Tire: Toyo RA1 or RR
  • Differential: OEM ratios: 3.73, 3.91, 4.10, 4.27, 4.44 and 4.45
  • Wheels: 14" & 15” diameter allowed
  • Brakes: Rotors and calipers stock, aftermarket pads allowed
  • ABS: Not allowed
  • Suspension: Open except remote reservoir shocks not allowed
  • Minimum weight with driver: 2,650 pounds
  • Minimum ride height: 5 inches to rocker panel

Full 2014 ICSCC Rule Book

PRO3 Specific Only (Link)