Injector Data

Dead Times (latency)

Fuel injectors are designed to deliver a specific volume of fuel every minute, for example, Flow Force Injectors deliver 640cc of fuel every minute they are open. When your engine is running at lighter loads, the injectors deliver short pulses of fuel. The engine computer will power the injector on for, say, 5 milliseconds, however it takes time for the injector coil to power up and open the valve to let the fuel out, and again to depower at the end of the cycle. The difference between the expected flow from a pulse

5ms x 640cc/min x 1min/60000ms = 0.053cc

and the actual fuel delivered in that pulse (0.04cc) is the injector dead time, also called injector latency. The example above implies a 1.25ms dead time:

(5ms - 1.25ms) x 640cc/min x 1min/60000ms = 0.04

Dead Times by Voltage and Fuel Pressure

Small (non-linear) Pulse Widths

All injectors become non-linear at very small pulsewidths. This is caused by things like the pintle half opening and such. Below are the small pulsewidth settings for MS3. As you can see, it's pretty close to linear, so a lot of folks don't bother changing this setting.