Piston Speed Calculator
Calculate mean and maximum piston speed.
Piston Speed Limits
| Engine Type | Max Mean Speed | Notes |
|---|---|---|
| Stock/Street | 3,500-4,000 ft/min | Cast pistons, stock rods |
| Performance | 4,000-4,500 ft/min | Forged pistons, good rods |
| Race | 4,500-5,000 ft/min | Full forged rotating assembly |
| Pro Race | 5,000-5,500 ft/min | Titanium rods, race pistons |
| F1 / Extreme | 5,500+ ft/min | Exotic materials, short life |
Understanding Piston Speed
- Mean speed = Stroke x 2 x RPM / 12 (ft/min)
- Shorter stroke allows higher RPM at same piston speed
- Higher piston speed increases stress on rods and bearings
- Ring seal becomes harder to maintain at high speeds