I have the G56 Stage 1 kit on my car and a standard ECU. I was told by the G56 people that their Stage 1 kit was designed to run within the programme of the standard ECU and it seems to do this very well. It doesn't make your ears bleed like the KH one I heard did, if that is a consideration.
Is your M3W an early, mid or late Mk1 or Mk2? Mine is an early Mk.1 (April 2012) so still has the earliest version of the software in the ECU. I believe this over advances the ignition over 4000 RPM so that a change in pipes is only a partial cure. Reading the G56 blurb I think their ECU has to be programmed on a rolling road. Maybe the ideal cure would be G56 pipes and a KrazyHorse ECU.
Sorry Wilson, please disregard my answer to your ECU question on another thread, as I hadn't read this one.
I am very reliably led to believe that the stock map in the stock ECU is actually quite well setup for an S&S motor which is allowed to breathe properly. The exhausts on these M3Ws have been progressively bunged up (the early cars were noisier and the prototypes that the mags reviewed way back, faster and noiser still). It is for this reason that the simple addition of a G56 Stage-1 kit does NOT impact the running of the car other than to improve things 100%. The stock ECU map can then work as expected, there is no pinking on large throttles above 4000rpm and the whole driving experience is MUCH improved.
However, as with all perfectionists and their requirements, the recommendation is perhaps further tune the setup to ones specific vehicle by use of a rolling road. This however is for the fine-tuning only, not the fundamentals. In fact pretty much any car will benefit from a 'remap', if only to maximise the setup on that particular car, irrespective of whether the owner if after more power or not. It'll just be better after a 'personal' tune.
I'd not hesitate to just put a G56 kit (other similarly free-flowing alternatives are probably available...!) on your car and let your stock ECU do the job for which it was designed. If I was nearer I'd come by and let you drive mine, so you could see for yourself.....
