Rotary Car Club - View Single Post - Can i use a low/high-imp injector combination?

RotaryProphet · 10-05-2009, 10:22 AM

The problem is, even with resistors on the low impedance injectors, you'll have two high impedance injectors that open at the correct rate (about 1ms before the start of fuel flow @ 13v), and two high impedance injectors (thanks to the resistor) that open more slowly (about 1.4-1.8ms @ 13v, depending on the brand.) If both injectors acted like that, you could tune around it by increasing the injector open time in the ECU, but you'll probably have some trouble tuning the transition from your primary to secondary injectors; bringing them in earlier to compensate for the fact that a 1.5ms pulsewidth is giving you basically no fuel.

It's definitely doable in a mainly street driven car, but it wouldn't surprise me to see some hesitation in there at the boost threshold.

10-05-2009, 10:22 AM	#4
RotaryProphet Rotary Fanatic Join Date: Sep 2008 Posts: 147 Rep Power: 17	The problem is, even with resistors on the low impedance injectors, you'll have two high impedance injectors that open at the correct rate (about 1ms before the start of fuel flow @ 13v), and two high impedance injectors (thanks to the resistor) that open more slowly (about 1.4-1.8ms @ 13v, depending on the brand.) If both injectors acted like that, you could tune around it by increasing the injector open time in the ECU, but you'll probably have some trouble tuning the transition from your primary to secondary injectors; bringing them in earlier to compensate for the fact that a 1.5ms pulsewidth is giving you basically no fuel. It's definitely doable in a mainly street driven car, but it wouldn't surprise me to see some hesitation in there at the boost threshold.