I have a ms1 with vr2 circuit and ignition control, can the ecu control high imp primary inj, and low imp secondary inj?

 

if you use resisters for the low imp injectors you will be fine.

 

I'm doing it. I just use 10 ohm resistors on the low z injectors.

 

ok, i guess i can use the rx7 s4 resistor, thx.

 

depends on the injector.

Measure the injector with a good multi meter. If you put a pair of 4.5 ohm injectors onto the 2nd injector driver, I have proven they can work just fine.

#1 They are secondaries so most of the time they are not used.
#2 By that time there are 4 injectors so the duty cycle is lower if you used big secondary injectors
#3 You can set the staging settings to make sure secondary injectors are not used until you absolutely need them ie until you hit 85-90% duty cycle on the primary injectors
#4 When the injectors are in use they are still subject to the pulsewidth in your fuel map so its not like you are putting a short circuit on an injector driver not designed for it they are an inductive load and it takes time for the current to ramp.