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M1 RPM based Auxiliary Output

MoTeC M1 Software Tutorial

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Greetings all.

Looking for a means to trigger VTEC solenoid based on engine RPM using an M130 with GPR. Looking at the Aux outputs, they seem to be limited by choice to either MAP or throttle percentage. Is this possible without having to use Build?

Honda F22C AP2 in a S2K race car.

I did that (use Aux Out 1, and just disable the Throttle Axis, but keep the Engine Speed axis, use 0 and 100% duty cycle) and was really unhappy with the results -- you want to have some hysteresis in the application of the VTEC solenoid (ie, goes on at one RPM, and doesn't go off until you go 100 RPM below that point) Because the moment you switch it, the engine might slow down slightly, turn VTEC off, then back on. Made a rough transition for the K20 with lightweight drivetrain installed in a Formula Atlantic race car.

In my case, I decided that the standard GPR package wasn't a good fit for this engine. I was going to modify it with M1 Build, but in looking around a found a better package to use for use with the Honda from, I used the K-Series engine swap package found here:

You can use the Aux outputs to achieve this aim. Depending on which aux output you use, you can set up the output duty cycle table based on rpm alone, rpm vs TPS, or RPM vs MAP. For a switched cam control system you just use 0% and 100% duty cycle and I'd suggest setting break points in the table very close at your changeover point - For example if you want to change at 4500 then have a point at 4490 and one at 4500, then set 4490 to 0% duty and 4500 to 100% duty. Setting up the output tables as a 3D table will allow you to replicate the VTEC window used by a stock Honda ECU.

Thanks for the replies David and Andre. Got it figured out today on Aux 3 with settings pulled in from the previous AEM EMS1. Can't wait to get it on the dyno and see how it works out.