ms2 extra 2.1.0
13b stock port with ITBs, 444cc injectors

i want to try to get a better understand of how these values effect the engines operation. below are the current settings.


currently i have 100% TPS based with the settings as follows

rate------value
1000-----15
800-------10.5
400-------5.0
210---------2.0


mapdot threshold 100
accel time 0.2
accel taper time 0.1
end pulsewidth 2.0

tpsdot threshold 200
decel fuel amount 90
cold accel enrichment 3.0
cold accel multi 130

 

The rate is how quickly the TPS changes percent in one second. The value is how much fuel is added for each change rate.

Your threshold is how much change it takes to activate the enrichment.

Accel time is the time during enrichment where the full enrichment amount is added. Taper is taper is the amount of time between full enrichment and the end pulsewidth.

Actually, I just Googled and here's the descriptions for the rest from the MS2/Extra manual:
http://www.msextra.com/doc/ms2extra/...ual.html#accel

 

so how abnormal are my current settings.

 

With those settings I would expect things to be very unresponsive, especially with ITBs. I would decrease your threshold to 70-100 to start, and do the same with your lowest %/sec number.

Ken

 

Acceleration enrichment is what confused me most about tuning and I'm still trying to get it right.

I'm running a 13b bridgeport with twin 50mm ITB's, 4x550cc injectors, also using 2.1.0 as you are.

My settings are currently as follows;



I'm sure they are far from perfect, but they may help give some insight. I still have a long way to go I think haha. Oh and if anyone has any suggestions for me as well, fire away (don't mean to hijack your thread Gravity Fed, just sharing info )

I have found with such a low threshold that AE can kick in when cruising which can make for unstable cruise - but I think it might be a problem with my tps. I have tried using a higher threshold such as 20 and a few in between, but it made it way less responsive which was a pain in the ***. It would bog down and carry on really badly on light throttle and just be a general pig when taking off from a stop etc..

The other thing that is easily overlooked is the Accel enrich settings. Are the default values for this OK? I didn't think they would be because my engine gets revved to 9krpm, I increased the High rpm threshold to 8krpm (should I make it 9?). My low rpm is the default 2500rpm, considering my car idles at 1700rpm, should this be altered? Hopefully these answers can help others too!

 

wow are my numbers way off

 

If you need such a small threshold, then the area just above your idle are in the map is too lean.

2% is going to activate the AE anytime there is just a little jitter. 10% is a much more reasonable value but even that is low.

Bridgeports need a lot of AE. On my Microtech, I have to double PW in order to get proper AE at low RPMs.

As well, what is your timing like? Bridgeports like a lot of low RPM timing.

 

Ah yes, well that helps a lot Aaron. I did have a suspicion that the threshold shouldn't have needed to be so low. I'll look at making some adjustments here.
The other problem is that I'm running speed density, which is not so good for the bridgeport. This is perhaps the other reason why it's so bad on the idle transition, because the map values at idle are all over the place (even with a custom vacuum reservoir). Doing my VE off map is never going to be responsive, considering I need so much room for my idle to swing about all over the place, by the time my map values have changed enough to get it out of the idle bins the engine isn't getting what it requires...

I was having problems tuning off alpha-n, but I think it is something I ultimately need to learn how to make work.

My timing map is a nightmare at the moment, but it looks like this;



I have just effectively locked the timing down low for now, like having a locked dizzy at 22 degrees. Seems to be fine like this, but I will need to fine tune it for best results. Any pointers there?

 

You should be able to run speed density just fine with a bridgeport. I am, and don't have any problems. Of course, with your ITBs it is probably a different story. I can't imagine that setup as any kind of a usable vacuum signal.

Your timing map looks quite a bit like the NA section of my timing map.

 

Keep in mind that if you are using a later firmware (2.1.0 or later I think) the thresholds were fixed. Previously they were off by a factor of 10.

So if you're using a setting of 2.0% in an old firmware you'll need to change to 20% in the newer firmware to compensate.

Ken

 

Ah, thats handy to know ken.
I was doing some tuning last night and I enriched the section of the map above idle and it loved it. But I still need to do a lot of work, as having the threshold at 20 still makes for some nasty driving characteristics.

I also revisited alpha-n, it worked absolutely great with my old tps values but terribly with the new ones, even with heaps of tweaking - in fact, the more I fiddled, the worse I made it haha.

 

Hey can I ask, should I have AE turned off to tune my VE table, then tune AE? because I've noticed that if I adjust my VE table using megalogviewer's autotune feature, it caters for my out of whack AE. Then if I make changes to the AE, even if they are for the better, it drives like crap. So should it be turned off when autotuning? before AE's have been perfected anyway.
Cheers,

Ben.

 

Megalogviewer should ignore AE. Check to make sure that setting is enabled.

You really can't tune AE until the VE table is done. Just get it in the ballpark and leave it alone until you have a working VE table.

 

oh ok, thanks so much for your help Aaron.

I do have a functioning VE table, I'm just trying to refine it I guess. It drives fine, my only real problem with the map seems to be on very very light throttle, just off idle etc.

I will look into this setting when I get home from work! I'll keep you posted, I should get a change to do some logging tonight. So we'll see how we go.

Once again, thanks all for your help.

 

im changing my threshold. ill see what that does tomorrow. as for the actual values. im going to mimic the 25,40,50,70 for now mostly because im not sure exactly how the changes will affect things.

so does having the rate say at "70%/s" mean 70 percent MORE fuel? I just want to verify. Also, how does the value in m/s play into things?

I redid some tuning tonight. Made some headway now that i have a wideband.

But its still rough at the high end (havent tuned there yet). I have the EGO control disabled for tuning. I have the fuel injectors running staged injection and under the injector characteristics i have both banks on. Which would only make sense to me since i have both banks of injectors wired. Is this correct? Bank 1 has one injector for each rotor as does Bank 2. So from what i gather, with the staged injection, bank 1 is operating til the set 3500rpms then bank 2 comes on as well.

 

basically im still having some issues with the car. Even while its saying its 12.5ish on the UEGO, im still getting something that feels like missing, so i need to go and check my ignition system (running the FB dist. with a multi spark box). Megasquirt is not controlling my ignition. Ill recheck the timing. I currently do not have the vacuum advance hooked up.

 

another thing i would like to mention is that with the TPSdot threshold at 2% and the settings listed like in evils pic, i only see max of 107% on the AE gauge ms has. So it seems to me like its NOT doing something.

 

yeh my tps thresh at 2% was incorrect as Ken mentioned. I've now changed it to 20% and I'm slowly making progress. Although your issue sounds odd...
Hopefully you can get it sorted!

I wouldn't mind some more input from others on things like accel time, taper time and end pulsewidth settings. It would be great if we had a database of AE settings for rotaries with different setups... say in this instance settings for people with 50mm throttle bodies running speed density or alpha n, or people running stock t2 intake with speed density or alpha n, and so on.

Surely AE settings can't be too dramatically different from wankel to wankel. Of course the value (ms) is going to vary quite a bit, but i'd imagine that all 13b's running twin 50mm tb's would require similar base settings.

 

im hoping that the issue is mostly just something with the tuning and maybe i have an exhaust leak that is making it sound like ignition breakup since i dont really FEEL it. I still have quite a bit of tuning to go...

Also discovered my radiator is leaking from a seam so i am going to limit how far away i drive the car for tuning now til i replace it.

 

I have a 4 banger tuned with MegaSquirt and it runs very well. I am now looking at a rotary MS installtion on my Son's first Gen. Back to tuning.

I had my son drive my car while I used the laptop and looked at the map. I Gave the ECU 20% Authority and watched the O2 sensor. Have the driver take his time in different gears and at different RPMs. See where the golf ball rides on the mesh and use the up down keys to adjust the mixture. Don't for get to save every few minutes or so. Accelleration enrichment was done in the parking lot by blipping the gas pedal and making adjustments. Because my piston engine was using a wild camshaft the time was shortened and the duration increased. This solved the starting from a stop light bog down problem. We ran the car almost 200 miles in 10 mile runs along a country road with lots of starts and stops. I used TPS Map as the MAP value pulsed wildly. Changing from MAP to TPS brought about a stable by high idle at the press of a button.

I used MS only for fuel control as ingnition was stand alone. Try and work on 1 problem at a time. There is so much going on and to learn and a rotary flooding is a pain to get unflooded.

I didn't have much luck with data tuning and auto tuning as it put plain stupid values in the fuel map. In one block I had a value of 180 in the next 5, Yup fall on that block and the engine bogged down. As the engine began to run better I increased the Authority to 35%, I am using a narrow band O2 Sensor.

TonyK.

 

Just some information that I think may help the OP and a couple of others. First the misfire, we had that for about a year and examined the pulses with all the test equipment in the world. What we were seeing was a momentary spike in the rpm signal that would make the MS think it was revving to about 14,000 rpm. All kinds of nasty things took over at that point as everything tried to limit the rpm. We finally cured it by updating the base version of the firmware. Dave (Aaron, you should remember him) saved the MS settings and transferred them to the latest firmware available and it made a night and day difference to the driveability of the car. Aaron, ultimately changing the firmware cured all the issues we were having with the car and getting it all set up.

The second thing we found that there was no way we could get any decent driveability out of the car with speed density. The vacuum basically drops to zero as soon as you tip into the throttle. You could tune the car for one scenario of throttle tip-in and it wouldn't work if you accelerated faster or slower. Trust me we tried everything and wasted a ton of time and money trying to get it to work with speed density. However I am concerened as we were trying to tune the car with the glitchy previous level firmware.

We went to Alpha-N and bit the bullet. After the firmware change everything worked out very logically. We were able to tune the car, get it to start easily and it ran great. It was fast enough to pass a 280 whp Super Touring car last fall in a straight line at Mosport. We ended up with some other issues due to low fuel octane and super high inlet temps, but the car ran great and everything worked reliably.

In my system, we are using a 4 port ITB system, which further reduces any vacuum signal and a 1/2 bridge. As well I am turning the motor to almost 9,000 rpm, but the car is making tons of grunt and pulls smoothly away from a stop at 2,000 rpm and above.

I don't know if this helps, but if our settings would be of benefit, I can get Dave to offer our settings for your review.

Regards,

Eric Nummelin

 

That offer, Eric, sounds brilliant!

I for one, would be interested in seeing the settings. I wish mine pulled smoothly from 2000rpm, having a brass button clutch doesn't exactly help the cause though.

Do you know what firmware was being run by any chance?

 

I have a 4 puck brass button clutch in mine as well, LOL. It can be a pain.

The other things are that my car weighs about 2300 lbs and that I am usually above 3/4 throttle pulling away. As well I have no emissions and a Racing Beat Race header and 3" single exhaust blowing through a 3" ID Borla. Stock S4 box and Stock '88 clutch posi with 4.10:1 final drive.

I will ask Dave to put together a bunch of our settings so that you guys can see them. We are still tuning, but its getting lots better.

Eric

 

ok, so I got a bit of time on a dyno. However, the dyno did suck.
It allowed me to smooth out my map heaps. look!

this is my old map


this is the new one!


I have found that my acceleration enrichment is now way off, but havent had any time to address it.
I will probably get a chance to do so tomorrow, well I hope so anyway. Then I will post up my results and settings.
I do hope I get some decent results as I have entered the car in a supersprint on sunday

 

ok, so racing was great on Sunday! The car held up fine, however the diff is now whining badly and the exhaust cracked so it's a lot louder now haha.

The bad news, on saturday we had very bad storms and my whole house ended up 6 inches under water. The racing took my mind off everything, but I had to come home to my sopping wet mess of a home. I'll get my settings posted up once I get everything sorted at home.