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I'm looking at setting up a "Flex Table" to operate an extra injector fitted to the intake side of the blower on the Dato. The injector is currently operated using a micro switch (in the positive side)on the throttle, so it starts about 2500rpm. I'm not sure what type of figures to install in the table. Should I switch with RPM or Boost? An example table to give me an indication may be a good thing(it doesn't have to be a complete table)
Thanks in advance.

so do you want this injector to only work at WOT and when under boost ? is it currently held open constantly with the micro switch or pulsed ?

It's currently held open, but I'd like to set it up pulsed. My idea would be to have it come on similar to now, so that it can help cool the blower when the car is staged.

i'm not sure how well its going to work ... VL400 can you advise what would be needed to interface it ?

personally i would hook it up to the normal injector pulses, then just lean the whole tune out by whatever percentage it changes ?

on a v6 you have the capacity to run another 2 injectors without any problems.

The flex output is a 32Hz PWM signal, configured as either a digital on/off signal or 0-100% duty cycle signal. The 32Hz signal means its 31.25ms per cycle, with the flex table setup as 0-100% duty cycle each % equates to 0.3125ms - this would be your pulse width resolution if using it to drive an injector. If the table was filled with 10% it would deliver a 3.125ms pulse

The flex table uses spare outputs on the ECU, they cant handle much current - they can drive a relay if you want to keep it as an on/off signal but cannot drive an injector directly.

Now as an extra injector driver the issue is its setup as fixed 32Hz frequency (and its slow, 32Hz = 1920RPM) instead of occuring in sync with the engine revs like the normal injector drivers. So below 1920 RPM it will be deliving more than 1 pulse per engine rev and above less than 1. Might be a problem if your injecting enough fuel to change the engine AFR?

You could have the table as MAP vs RPM. Or even using charge temp vs MAP, so if the intake temp gets too hot under boost it can inject some fuel to cool it. How you set the table up is pretty flexible

VL400 wrote:How you set the table up is pretty flexible

oh that is lame dude

So I could hook up the flex outlet to a relay to operate on the positive side of the injector with the negative side tapped into the pulsed neg. side, correct?
In the mean time I'll tap into the injectors & lean out the VE tables, as we're racing on Sunday at Wellington.

Yeah should be able to do that but might take some playing to get the AFRs back to normal - just dont add too many extra injectors as the ECU might start to get un-happy with the extra load!