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Hi guys, im struggling with the transition from 2000rpm/2500rpm (idle) no load area to then opening the throttle under light load. Theres a lot of hesitation flatspots, missing etc. Then from 3 to 4k she clears up and goes.....afr's look ok at that point.
Acceleration enrichment is set up with 80% sensitivity.....do I need more fuel sooner or more timing?? MotecM4 ECU
Are you aiming around lambda .85 during transition? Is it a factory manifold/injector location or injection throttle body? Throttle body injection needs heaps of transient enrichment.
Yes its factory manifold and injector location.
Depending how aggressive the bridge port is, you may struggle to get perfect driveability. I'd liken it to a piston engine fitted with a large cam - You need to understand the implications and the limitations that it will pose. That being said, it could very well be tuning related. one of the common issues I see with rotary tuning is to do with the staging of the secondary injectors. I'd may special attention to whether the secondary injectors are beginning to come in around the point you're having issues. The other aspect to consider before you start adjusting accel enrichment is whether the fuel table is properly tuned under steady state conditions in the areas you're having trouble.
OK thanks guys.
It may feel lazy but you shouldn't be missing/stuttering at that RPM with even a giant bridges overlap. I'd be more than happy to lend a hand but I'll warn you it's been like 10 years since I've used an M4 or M2R so I have to see if I still even have a computer to run the OG software.
Hey M:EP thanks for the offer but I have just drained all the fuel and stored her. I enriched the fuel up a bit earlier in the transition and it did help out a bit.
Cool beans, glad it worked out somewhat. With some of the older ECUs (even motecs) that have rudimentary transient throttle strategies it can feel like you're going overboard with fueling on rotaries, but they like what they like. I did dust off an old dyno machine with XP and motec's old EMP software suite. Ugh its ugly.
If you have troubles getting low load working for you on a rotary feel free to shoot me a message.
Thank you. Will keep that in mind.