Bore / Stroke / CH Calculator
Racers Place • Professional Tools
This calculator allows you to test piston + rod combinations for a given block height. It automatically calculates deck clearance and engine displacement.
Deck Clearance: in
Displacement: CID
📘 Theory
- Deck Clearance = Block Height − (Rod Length + Stroke / 2 + Compression Height)
- Displacement = π / 4 × Bore² × Stroke × Cylinders (default: 8)
- A negative value means the piston comes above the deck — which may cause mechanical interference.
📐 Purpose of the Calculator
- Match the piston compression height to the chosen block height, rod length, and stroke.
- Aim for a safe and suitable deck clearance.
- If the value becomes negative, the piston rises above deck — usually meaning the CH is too high for this setup.
- Typical clearances:
0.000" (zero deck) for performance builds
0.030"–0.050" for most street/strip engines