Engine Builder Calculator
Calculate engine displacement from bore and stroke, estimate mean piston speed and explore power-to-displacement ratios.
✔ 100% free
Mobile friendly
⚡ No account
Loading tool…
Advertisement
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
FAQ
2 × stroke × RPM ÷ 60 000, in metres per second. It is the single best indicator of mechanical stress in the bottom end.
Advertisement