Supercharger Pulley Ratio & Boost Calculator
Liguori Drag Racing • Forced Induction
All calculators / Forced Induction
Supercharger Pulley Ratio & Boost
Compare drive speed and an ideal positive-displacement airflow ratio.
Starting values are examples. Enter your measurements; results update as you type.
Method & assumptions
Positive-displacement blower only. Rotor speed = engine speed × crank / blower pulley × internal multiplier. Ideal volume ratio = 2 × blower displacement × drive ratio × blower VE / (engine displacement × engine VE). Gauge boost assumes equal inlet and manifold temperatures; leakage, heating and restrictions change actual boost. Check manufacturer rotor-speed limits separately.