[FW MOD] ms2extra 3.2.1 beta gslender v2

This is a forum for discussing the development and testing of alpha MS2/Extra code. Documentation
(Runs on MS2 and Microsquirt)

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muythaibxr
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Joined: Thu Oct 14, 2004 12:48 pm

Re: [FW MOD] ms2extra 3.2.1 beta gslender v2

Post by muythaibxr »

I actually implemented something like that and tested on my own engine once several years ago. It didn't really help much on my particular engine and I was never really happy with it. I got much better results by increasing the number of squirts as far as I could (4 alt on that engine), and by setting the lags on tps and map as close to 100 as I could. This was on a 4 cylinder with ITBs. I was finding that the table lookups when using SD lagged far enough behind actual conditions otherwise that nothing I did could fix it. Squirting another pulse just made things go excessivly rich after the initial lean spike.

That said, I achieved the best results by going to sequential fuel. Also, I have found the off idle stumble many can't get rid of is because of incorrect ignition timing in the area just above idle. Tuning that properly helped me immensely.

Finally, I have found that in the existing AE code, the AE shot doesn't really start until the mainloop iteration after the one that the initial TPSdot > threshold happens. In our MS3 accel pump code, I have solved that problem, and those who have tried it have noted that it is easier to tune, more responsive, and has less deviation of AFR compared to the normal algorithm.

We also want to eventually extend in-progress squirts to help response even further.

Ken
Megasquirt is not for use on pollution controlled vehicles. Any advice I give is for off road use only.
Black99rt
Experienced MS/Extra'er
Posts: 364
Joined: Tue Mar 14, 2006 10:38 am

Re: [FW MOD] ms2extra 3.2.1 beta gslender v2

Post by Black99rt »

Can you add a few comments on ignition timing or tuning procedure for that critical area?
1999 Dakota 5.9L R/T-
MSIIe 3.1.2 Batch Fuel/MSD single coil dizzy/Stepper idle
LC-1
muythaibxr
Site Admin
Posts: 8228
Joined: Thu Oct 14, 2004 12:48 pm

Re: [FW MOD] ms2extra 3.2.1 beta gslender v2

Post by muythaibxr »

I just experimented until i got the result that I wanted. In my case it turned out that in that area of the table I didn't need to reduce the timing as much as load climbed, and i needed to have what reduction there was be very smooth. So I had the timing at 12 deg around idle, and when it stumbled I had it go to 8 at the top of rhe table. I changed it to go to 10 instead without changing at all until 4 bins above idle and that smoothed it out considerably. Then I turned on EAE and tuned that a bit which basically made off idle and slower throttle movements as good as factory. I used a tiny amount of regular AE to fix up quick stabs and things like rev-matching for downshifts.

Ken
Megasquirt is not for use on pollution controlled vehicles. Any advice I give is for off road use only.
Black99rt
Experienced MS/Extra'er
Posts: 364
Joined: Tue Mar 14, 2006 10:38 am

Re: [FW MOD] ms2extra 3.2.1 beta gslender v2

Post by Black99rt »

Thanks.
1999 Dakota 5.9L R/T-
MSIIe 3.1.2 Batch Fuel/MSD single coil dizzy/Stepper idle
LC-1
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