I have an S5 motor sitting in my garage ready to go into a custom built chassis and am considering my options of either using the stock ECU or going MS. Now please keep in mind i'm not a MS n00b, i've MSnS'd a few watercooled VWs in a past life but when it comes to controlling all of the funky *** (no offense intended) rotary systems (ie. VDI, OMP, 6 ports and the several solonoids) i'm at a bit of a loss... I do not need to worry about emissions and not really looking for MAX horsepower so if i need to swap out the VDI or something it's not the end of the world. I'm not looking for a plug and play system, i'm more than capable of building the board and wiring harness but i'm more concerned about what has already been pioneered regarding these non-conventional obstacles on the S5 motor. thanks for your time.

 

VDI and AUX ports are no problem. I wouldn't worry about any of the rest of the solenoids as most of them are emissions related. You'll need to premix however, the MS can't control the OMP.

I'd definitely use the VDI and aux, as both make a significant difference. On tofuball's S5 'vert (the first rotary to run stock ignition on the MS), we noticed a significant difference about 5000 rpms in power with VDI on vs VDI off. It showed in the fuel table as well, we needed significantly more fuel with VDI and AUX working.