Fuel flow rate through an injector is affected by a number of different things. This page focuses on the effects of the ECU's internal driver circuitry. Differences in design can influence how an injector responds. This adds yet another layer of difficulty to getting usable numbers from an injector testing service. If they're not using the same driver circuitry as you're using, then the numbers (primarily deadtime) aren't going to mean much to you.

Unless your injectors are being flow tested using the exact same drivers as are found inside your ECU, you can expect to see different behavior (primarily deadtime related) when installed inside your car. A common driver for many flow testing stations is the “standard” 4:1 peak/hold driver.

The problem is that our stock Mitsubishi ECUs (at least everything before the EVO X) uses an entirely different driver circuitry. So the numbers collected on many of these standard flow testing stations for injector deadtime really have no bearing for our factory ECUs.

To illustrate this effect, refer to the chart below showing the exact same FIC BM1450 injector being run with a standard 4:1 peak/hold driver vs. our Mitsubishi ECU driver.

Click to enlarge