Meth / Fogger / Nitrous external controller

I've been looking around for a controller that would allow PWM control for the Meth injection system and/or Nitrous injector among other things using IAT, Boost, EGTs and RPMs as reference.

Most off the shelf controllers are "dumb" just using a linear control with two knobs.

The car is tuned by ECU reflash so no additional accesory triggers thefore I've been looking at the possibility of building a megasquirt like system just to control all mentioned above.

Any recommendations, suggestions?

Thanks in advance.

A basic ecu is probably the best way of getting the control you want without having to write your own code or rely on something whose operating system doesn't prioritise function control. I'd suggest adding a relay in line with the boost solenoid as a failsafe if you can't integrate control with the engine ecu.

The idea is to be able to have electronic boost control under the same unit too, instead of having different solutions that don't talk to each other. Since it's been tuned using ECU reflash, unfortunately I don't have aux outputs.

Right now the wastegate control is being done by a spring bolt setup, not even actuators with bleed valves and since it's a twin setup in series... it's kinda difficult and time consuming to dial them in using the drive pressure gauge and butt dyno. Going with an EBC would allow more tunability for the meth injection / nitrous and boost management of both turbos.

The issue I see with using an external controller that can't interface with your ECU is that you have no easy way of trimming the timing or fuel when the nitrous is active. Nothing specifically wrong with using an external controller but it's more to do with the interaction between that and your ECU.

I forgot to mention that it's a Diesel. Currently I'm using spring gates but the adjustability by trial and error is just painful hence the journey of an external EBC and other controllers for other accessories.