Alternative Lumpy Idle Tune Switch Question

Hi All.

Have a Rb26dett with the factory AWD 5-Speed controlled by a Haltech Platinum Pro Plug-In.

My current tune is flawless. Everything is great. Except it doesn't have a lump idle. Driving in the carpark is perfect. I have enabled rotational idle and removes the smoothness of the tune out and makes it more lumpy. However, (surprise surprise) driving in the carpark at low RPM is interesting at best. I have set the rotational idle to come on bellow 1% TPS and bellow 1800rpm.

However I have come out with a idea and want to hear everyone's thoughts if its going to work.

The rotational idle can be turned on and off via a switch. I am thinking of splicing in the clutch switch and neutral switch into the ECU.

That way I tell the ECU, if the clutch is engaged enable lumpy idle OR if the gearbox is in neutral enable lumpy idle.

In my head this works in theory. In practise, I am not sure. Both the clutch switch and neutral are 2 pin. Unsure if they are normally open or closed circuits.

Love to hear everyone's thoughts.

Thanks, Andrew

To be blunt, my thoughts are it's plain stupid.

However, you could use a very rich mixture and, maybe, a retarded ignition at low rpm - that would help replicate the poor combustion characteristics a lot of valve overlap causes that results in the "lumpy idle".

Actually run aggressive cams, injectors and a massive turbo. Or just enjoy your driveable car.

And logic for rotational idle should work but unless you are going to open the stop a bit more and actually use it as an efficiency/cooling thing I wouldn't bother, possible compromise on engine braking there too which you may or may not like.

I don't know if Haltech has "virtual parametric output (that's how it's called in ECU Master)" that can be used with math logic (and, or, greater than, etc...), but with those you could use pretty much any parameters you want (VSS, clutch switch, neutral switch) for activation.