Cool. Thanks a ton! Now I just have to figure out the unit/scaling used in Kpro

 

255 is the maximum value because the base fuel table is based on 8 bits (0-255).

Multiply the value in the table by the MicroSec/bit value to determine the length of the injector pulse in microseconds. Most calculations are done in milliseconds, so divide that answer by 1000 to convert from microseconds to milliseconds.

The time for one complete engine cycle in milliseconds is 120,000 divided by the rpm.

The duty cycle is the pulse width divided by the time for one complete engine cycle.

Here's an example:
Pulse width = base fuel * MicroSec/Bit / 1000
Pulse width = 200 * 30 / 1000 = 6 milliseconds

Time for one engine cycle = 120,000 / rpm
Time for one engine cycle = 120,000 / 5500 rpm = 21.8 milliseconds

Duty cycle = Pulse width / time for one cycle
Duty cycle = 6 / 15 = 27.5%

You can check all of these calculations by right clicking on the fuel table and changing from raw, to pulse width, to duty cycle.

Tim

 

This isn't quite right.

100% duty cycle could be reached before 255.

You can also reach 255 without being at 100% yet.

The calculations above can explain.

If anybody wants it, I have an Excel spreadsheet with all of this inputted.

Tim

 

LOL, finally somebody who knows what they are talking about!