Please Explain Accel Settings

AbeFM · Post by **AbeFM** » Sun Mar 16, 2008 11:45 am

There are only a few settings in the Accel (non EAE) settings, maybe 8 boxes and a slider. A few friends and I have been trying to get it to work, and while I've gotten it a lot better by taking all the MAP based values and multiplying them by 100-500, it doesn't seem right, plus anytime I lift even BARELY on the gas before a shift the car lurches hard to a stop.

Something akin to a manual would be good, so I know what are REASONABLE (within a factor of 10) numbers to start with, and what going either direction does.

It's pretty cryptic reading the MT screen.

Thanks!

AbeFM · Post by **AbeFM** » Mon Mar 17, 2008 12:58 pm

Well, the first thing I've noticed - admittedly, this is on a pretty modern engine, overhead cams and port fuel injection (ha!) - having adjusted all the settings to extremes, my car is SO snappy now on the gas, even with my little 1.8l in a relatively heavy car, it's neck snapping when I touch the gas.

And the "accel enrichment" guage never gets out of the 98-102% range. The closer it is to 100%, the better the car feels. So I guess I need to figure out how to have it do something, but do very little.

But it IS like night and day, the car is hilarious to drive now.

6040solder · Post by **6040solder** » Mon Mar 17, 2008 1:11 pm

I found that on mine too. Just worked (tm). No fancy stuff required. Still, they say that it is needed on such engines anyway because of the head of the valve etc still getting wet.

cguenther · Post by **cguenther** » Mon Mar 17, 2008 11:22 pm

http://www.megamanual.com/megatune.htm#ta ? does this explain your questions?

AbeFM · Post by **AbeFM** » Tue Mar 18, 2008 10:11 am

Wow, thanks, yes! That's exactly what I was hoping for. I think all too often I assume the MS-IIx stuff is too different from the older stuff, and I don't look at the "old" manuals.

Thank you very much!

If anyone has reasonable numbers that work well on a similar motor (DOHC with port injection, 4 banger if that matters, bank fueled) it'd be nice.

If I totally shut it off, I get a SLIGHT hesitation, but it's hard to set it up so I don't get "steady state" surging.

AbeFM · Post by **AbeFM** » Wed Mar 19, 2008 9:24 am

I've been thinking perhaps I should try to tune just MAP based, then TPS based, one at a time?

One thing I've noticed, the car is ANYTHING but smooth during cruise. While the little bar-graph to show you what kpa/sec you're at only goes to 300, if I set my MAPdot threshold below 500 it feels like the motor has a skip in it.

Suggestions?

hassmaschine · Post by **hassmaschine** » Wed Mar 19, 2008 10:49 am

it's MAP based that's causing your problem - with a noisy map signal, I was getting PW dropouts during cruise. It was very annoying, and no matter how small I made the values it still did it.

I've basically stuck wtih TPS based while I fine tune my VE table, and it works okay, but I really want to get EAE well tuned. I've just never been able to fully understand it yet.

AbeFM · Post by **AbeFM** » Wed Mar 19, 2008 12:08 pm

When I first added in MAP, the usefulness in actual accel was marked - everytime I'd try to pull out of a parking spot or some other "normal" function, it would be SO responsive I'd spin my considerably sticky tires. It felt like I was driving a blown 454, not a low compression 1.8l

But under cruise it was essentially impossible to drive. I could add move averaging to the MAP signal overall, but it's really not needed (I think?). Perhaps an added feature would be smoothing on just that signal?

Again, perhaps I'm not clear enough on how it works. It helps but it's very hard to get right.

AbeFM · Post by **AbeFM** » Wed Mar 19, 2008 2:55 pm

Hass,
not to look a gift horse in the mouth - please, share any experiences you had with getting the TPS method working. While I think the map-based should really hold some capability, I'd love to just get things working reliably. Every thing that is set up wrong makes it harder to tune the rest so any advice is appreciated. What numbers you used or tricks you employed I'd love to hear about.

mops · Post by **mops** » Wed Mar 19, 2008 4:35 pm

unlike most people, my setup seems to be very specific and ae is very hard to tune. too little and i get hesitation/misfires, too much and i get flooding/wierd noise/hesitation... I suspect that is because of the injectors that i use... these are stock injectors, and they shot a steady stream of fuel, not a spray/mist. no, they are not dirty, they are just like that.

anyways... tps doesnt really work well for me, because on low engine speeds, small tps movement's cause large map changes. and it is vice versa at high rpm's. so it's impossible for me to get both good off idle response and reline gear changes working correctly

for basic ae i found abour 60-70%map, 30-40% tps working ok.... with log map lag, map is taking care of low rom/low tpsdot/high mapdot ae, while for redline wot gear changes are easily adjustable by tpsdor. this is accomplished by using correct tresholds and ae bins in both map and tps dot scale.

important thing.... very well tuned ae is crucial, if you want to have smooth throttle response while being tuned at the very edge of lean misfires. I run in 17.5:1 +-0.3 afr at cruise, engine will run up to 18:1 afr. any throttle changes, ae must deliver fuel asap, so that engine does not go any leaner than that. now if i wwas running 16:1 afr cruise, i would still have alot of 'safety treshold' therefore sortof sub tuned ae would work. extending that idea... if you were running 12:1 afr all the time, then you would not need any ae.... well maybe for quick stabs off idle... so my point here is that it's hard to comment on quality of tune of ae unless you are running at the lean limit...

hassmaschine · Post by **hassmaschine** » Wed Mar 19, 2008 4:47 pm

that's not neccesarily true - I've tuned my cruise areas to be a flat ~14.7:1, and with no AE I'd have lean spikes on throttle stabs and transients up to 19:1 afr. fortunately my engine seems robust enough that it's never been a problem!

What I'm really inspired by is the datalog of a car tuned by ken (EAE) during an autox with a completely flat curve through all kinds of load conditions. Mine is getting closer but I guess i'm a bit obsessed with smoothness now

Post by **muythaibxr** » Wed Mar 19, 2008 4:54 pm

Yeah, that tune didn't take that long either... I spent a bit of time messing with the best number of squirts, then turned on EAE, and tinkered with it as my friend was driving.

Ken

mops · Post by **mops** » Wed Mar 19, 2008 5:56 pm

muythaibxr wrote:...and tinkered with it as my friend was driving....
Ken

priceless.....

at one stage got my engine fro smooth response, but the response was too slow... transistent was OK, but gear changes (low or high rpm, any gear)... it was not a miss or hesitation.... it was like hitting a large animal on the road...

right now i have it tuned better BUT it goes plenty rich on liftoff....

AbeFM · Post by **AbeFM** » Thu Mar 20, 2008 1:45 am

I set MAPdot settings all to 0, and the TPSdot to really rich, and slid the slider back and forth.

I was able to get the low speed stuff pretty good. But the high load conditions need work.

The Advanced stuff is a big step to take, if I can't get even a basic outline of the basic version, do I really want to get into something with 10 times the variables?

Post by **muythaibxr** » Thu Mar 20, 2008 7:51 am

For some engines, just turning on EAE with the defaults has ended up working better than the standard AE, so it might be worth a try.

Post by **muythaibxr** » Thu Mar 20, 2008 7:52 am

mops wrote:
muythaibxr wrote:...and tinkered with it as my friend was driving....
Ken
priceless.....

at one stage got my engine fro smooth response, but the response was too slow... transistent was OK, but gear changes (low or high rpm, any gear)... it was not a miss or hesitation.... it was like hitting a large animal on the road...

right now i have it tuned better BUT it goes plenty rich on liftoff....

Yeah, Like I said, you have to tinker with the number of squirts, lag compensation, etc... to get it right.

There might be something specific causing you problems, but it's going to be hard for me to figure that out without sitting there trying to help you tune it. Forgive me for forgetting, but what kind of engine is it?

Ken

AbeFM · Post by **AbeFM** » Thu Mar 20, 2008 9:34 am

mops wrote: for basic ae i found abour 60-70%map, 30-40% tps working ok.... with log map lag, map is taking care of low rom/low tpsdot/high mapdot ae, while for redline wot gear changes are easily adjustable by tpsdor. this is accomplished by using correct thresholds and ae bins in both map and tps dot scale.

Oh, interesting. After messing around, it seems I got the low end working well with TPS but not the high. I'd be curious to see what your values are - could you share, along with a brief categorization of your motor?

I thought I had the tps thing working well, but I still feel like I'm driving over a bumpy road, the car constantly has these minor bucks and surges which are really annoying and definitely take away from the smooth feeling the MS gave me before I started messing with things.

AbeFM · Post by **AbeFM** » Thu Mar 20, 2008 10:10 am

James,
Sorry, I missed your post there. Ok, I might try the advanced stuff, just to see what it does. I want to mess with anti-lag, too, but one thing at a time.

The motor is a 1.8l DOHC 4-cyl port injected, '00 miata, with a turbo added.

AbeFM · Post by **AbeFM** » Fri Mar 21, 2008 9:09 am

Ok, a couple new things.... And more work for me.

First off, I tried EAE, and the car wouldn't idle and barely ran even with my foot in it. So I put it back. All down the road, bumpy ride like I've had for the last few days. The MAP accel light was flashing on and off.

Question: I took all the MAP (ms) values and turned them to zero, my logic being I could use the map/tps slider as a scale-factor so I could make one change at a time instead of 4 or 5 each time I wanted more or less fuel. This seemed to work really well. Is my logic right there? Does setting the MAPdot values all to zero mean it won't add or remove any fuel based on that (Decel Fuel Amount is set to 100%)?

Anyway, the big news is I'd used the shortest hose I could for the MAP signal, I'd taken out an extension I had in there a few days or a week ago. For kicks I put in the extra length, and I think it fixed everything back up. My guess it was a little too tight around a bend and was restricting flow. So back to the drawing board on getting the accel settings to work better.

Still, I'd like to know if I can tune TPSdot and MAPdot settings independently by taking the "Value (ms)" numbers all to zero on one side or the other, or if there are more hidden things going on.
Thanks!
-Abe.

Post by **muythaibxr** » Fri Mar 21, 2008 11:09 am

AbeFM wrote:Ok, a couple new things.... And more work for me.

First off, I tried EAE, and the car wouldn't idle and barely ran even with my foot in it. So I put it back. All down the road, bumpy ride like I've had for the last few days. The MAP accel light was flashing on and off.

Did you reboot after turning on EAE?

Question: I took all the MAP (ms) values and turned them to zero, my logic being I could use the map/tps slider as a scale-factor so I could make one change at a time instead of 4 or 5 each time I wanted more or less fuel. This seemed to work really well. Is my logic right there? Does setting the MAPdot values all to zero mean it won't add or remove any fuel based on that (Decel Fuel Amount is set to 100%)?

Anyway, the big news is I'd used the shortest hose I could for the MAP signal, I'd taken out an extension I had in there a few days or a week ago. For kicks I put in the extra length, and I think it fixed everything back up. My guess it was a little too tight around a bend and was restricting flow. So back to the drawing board on getting the accel settings to work better.

Still, I'd like to know if I can tune TPSdot and MAPdot settings independently by taking the "Value (ms)" numbers all to zero on one side or the other, or if there are more hidden things going on.
Thanks!
-Abe.

The best way to tune is to use the blend slider and move it all the way to one side or the other... I'm not sure why you'd want to set all the numbers to 0 instead. You *can* do that, but I'm not sure I understand why you'd want to.

As far as the EAE stuff, if you didn't reboot the MS after turning it on, that could be part of the problem... Also, if the settings are too far off for your engine, it may oscillate a lot causing it to be hard to keep the engine running. Also, EAE can do odd things when the MAP signal is jumpy.

Ken