To determine the corrected displacement for classing purposes, the following formulas will be used:

1. Rotary: Actual displacement X 2.0

2. 2-Cycle Engines: Actual displacement X 2.0

3. Forced induction: Actual or corrected displacement X 1.5

A. For each additional forced induction unit 0.5 should be added to the forced induction displacement modifier (e.g., twin charged, twin turbo: Actual corrected displacement X 2. Quad turbo: Actual displacement X 3).