Engine Builder Calculator

Displacement and piston speed

Displacement per cylinder = π ÷ 4 × bore² × stroke × cylinders. Mean piston speed tells you how hard the engine works mechanically.

• Street engines : piston speed under ~12 m/s is safe for reliability
• Race engines push 22–25 m/s with special components
• Bigger stroke raises torque but limits safe RPM
• Bigger bore raises RPM capability and high-end power