Thunderace EFI - Day 9 using MSExtra 3.0.3u

Another chance to do a bit on the engine today, and it's been a while, but I have been on holiday for a few weeks.

The bike was resistant to starting on the low battery. It wouldn't quite catch, so I checked the fuel...and that was that

More fuel in the tank and after a short time I switched on the LC1 and immediately noticed the engine was running weak, so I decided to tweak the WUE values closer to stoich, and continued to do so as the engine warmed. The idle was relatively steady, the VETable 2 SD blue dot holding in a tight group, and then the fan cut in...suddenly the engine went richer. I had noticed this before, and homed in on the voltage compensation for the injectors, so I tried to bring this closer to stoich, by reducing the compensation...however when the fan stopped the previous stoich setting was too weak.

I jumped a battery across the system to try and stabilise the fluctuations, but it made hardly any difference. I tried reducing the injector time, required fuel, VETable bins etc and modding the correction, but it was never 100%. I need to mod the dash next to view in realtime battery voltage, PW and AFR, as I think this is the main reason for my idle fluctuations, and taking a snapshot will prove this. I know I can use MLV, but this is good enough.


The screenshot above from the left after the fan cuts in, and the engine is too rich, when it stops it's close to stoich, AFR=14.7:1

Interestingly there is no lag compensation for "battery voltage", yet there is for other sensors, and other stuff.

The other few things I tried was very small throttle openings and tweaks to the SD VETable 2, just off and around idle, and at the same time maintain close to stoich, which is not what you’re supposed to do, as you try to get the lowest MAP value & smallest fluctuations in RPM, but I can refine this later with a target AFR table. By the time I had enough, it was starting to get very much smoother, and I really enjoy working with the TunerStudio software.

Incidentally, I did try MegaTunix in a back to back attempt, but I couldn't get the USB Serial adaptor to be seen in X11, and so I must be doing something wrong.