Calculators & unit conversions

The Calculators menu gathers tools that work out the numbers behind a tune — how much air the engine moves, how much fuel that needs, what a turbo has to deliver, the engine’s mechanical geometry, and cam timing. They are reference calculators: they help you arrive at target values, they do not change the calibration themselves. Open any of them from the Calculators menu.

The calculators

• Air Flow Estimation — the engine’s air demand, as CFM and mass flow.
• Fuel Estimation — fuel demand and injector sizing.
• Turbo Calculator — compressor flow, pressure and the operating point.
• Mechanical Calculator — displacement, compression ratio and piston motion.
• Cam & Valvetrain — cam timing, valve/port and spring dynamics.

Passing a result along

Several calculators can hand a figure to another, so you do not have to retype it: Air Flow can send its CFM to the Cam calculator, and the Turbo calculator’s operating point can send its mass flow to Air Flow, its AFR to Fuel, and its CFM to Cam. This lets you carry one calculation forward into the next.

Unit Conversions

The Unit Conversions window converts the everyday quantities you meet while tuning, in five panels:

• Displacement — cid (in³) ↔ cc (cm³).
• Power — hp (PS) ↔ kW ↔ hp (mechanical).
• Torque — Nm ↔ ft·lb.
• Pressure — bar ↔ psi ↔ kPa.
• Temperature — °C ↔ °F.

In each panel, type a value under From and pick the from/to units; the converted value appears live under To, with a button to copy it to the clipboard. Clear All empties the input fields while keeping your unit choices.

Figure 1

See also

• Air Flow Estimation
• Fuel Estimation
• Turbo Calculator
• Mechanical Calculator
• Cam & Valvetrain