I have one Renesis engine to set up with a Microtech ecu. If its successfull I'll have another 14 to do. The only problem I see is the OMP. The MIcrotech can't control it, can a simple circuit be made that uses the 360 TPS as a reference? I believe the OMP works on 0 - 5v, does it need 5v at idle or WOT? Has anyone done something like this?

Thanks

 

I don't have any answers for you but I do have some suggestions.
Get ahold of a datalogger. I think rpm, throttle position, and MAP would be most important for comparison to the input to the OMP motor. If you can determine how the OMP preforms under a known set of circumstances it should be pretty easy to mimic with a little hardware, mybe even off the shelf stuff if you are lucky. I doubt that the OMP is driven off 5V maybe controlled with 5V most likley PWM.

 

It's a 4 wire stepper motor with a potentiometer that provides position feedback to the ECU. It's way beyond a simple PWM.

 

What application are you going to be using the RX-8 motor on?
If it's in the stock location then use the Microtech as a piggy back and leave the stock ecu to control all the regular functions.
If it's on a transplant setup then you got a couple of choices. You can pre-mix or select an ecu that can control the omp.

 

These engines are for aircraft so the factory ecu is out of the question. Motec is too expensive and I would like to stick with microtech as I'm familiar with them and they're good value for $. Premix is also out of the question, the renesis uses 2 oil injectors per housing sqirting directly onto the irons. This isn't just for lubrication but also to keep them cool around the exhaust port area. Obviously earlier engines don't need this cooling function so premix is fine. Apparently microtech are have developed a 'box' to control the OMP from Series 5 onward, I'll know in the next few days if they're available.