OFT - Guide To Dialling In Your OTS Base Tune

[Wayno]

Originally Posted by phrosty

You can even adjust the resolution of the load limits if you have lumps that won't go away because they're in-between the existing bins.

You can do this, but I found it increases the amount of work and complexity you're in for. Better to draw a straight line between two points and have your AFR in the ballpark than have to visualize a multi point graph in your head. Just try to line up the points where changes drastic changes in your afr/ve occur and hope the characteristics between those points are also a straight line.

[Wayno]

Originally Posted by solidONE

How are you guys deciding how the load limit tables are scaled? I noticed on the tables at 3800 rpm the load limit is set lower than the fields before and after it. What do I need to look for in the logs and how should I be taking the logs (uphill pulls etc.) to get this dial in more accurately?

I've made adjustments to my load limits that are a bit more suitable than what Wayno posted, but I'm still not quite happy with the result. I'm not getting any knock correction there, so it's not a huge deal. But, I'd like to get this dialed in my E85 rom before I run down the rest of this tank of E85 and switch back to petrol.

Are the load limits set based on the peak engine load seen at a given rpm? If so, I'm seeing as much as 1.23 g/rev at very low RPM right when I open the throttle fully. as low as 2300rpm. Do I dial the limits to those numbers, or disregard those load numbers completely since numbers that high is only seen when going from low throttle openings to fully open?

With Wayno's load limit tables applied (lean spot at 3600) :
http://datazap.me/u/solidone/plm3-fp...6-634&mark=534

After adjustments (no lean spot but really rich at low rpms):
http://datazap.me/u/solidone/plm85c-...zoom=8867-8990

Those logs aren't useful without the corresponding tables.

[solidONE]

Originally Posted by Wayno

Those logs aren't useful without the corresponding tables.

I'm on my 4th revision at the moment. Let me get my stuff in order and i'll post up. All the stuff is on my laptop, since romraider stopped working on my windows XP desktop for some reason. I tried setting it to peak loads seen at each rpm field below 4000 and that didn't go very well haha.

Edit:
@Wayno

Load limit tables in order of the 3 logs linked below ( table A and B are identical):


Using your EL load limit tables unedited on my E85 rom:
http://datazap.me/u/solidone/plm85b?...2274-2263-2253

Edited after having chatted with you in PM:
http://datazap.me/u/solidone/plm85c-...zoom=8867-8990

First log of my 4th and current revision I decided to go WOT at a much lower RPM just to see what kind of loads I was hitting. I don't think anybody drives like this under any situation. only for testing purposes:
http://datazap.me/u/solidone/plm85g-...zoom=2077-2213

My approach was to set the RPMs at the peaks and valleys of the engine loads seen while WOT. At first I set the load limit to roughly the peak g/rev seen at each RPM, then I went from there adding or subtracting the load limits from each field according to recorded afr compared to commanded afr. Also taking logs before it had enough time to adjust LTFT to effect OL afr readings. Although, one variable I did not account for was IAT's and ambient temps. I figure my MAF scale was pretty good in CL with the fuel trims staying within +-3% while operating in a fairly broad range of temps, so I didn't want to make it more complicated by throwing in a temperature variable.

I don't know whether if I'm getting too anal with these adjustments, as there doesn't seem to be much effect in terms of knock or even power output with it running above or below target afr at such low rpms. But, hey... since I'm already messing with it, might as well try to get it as close as I can. lol

[steve99]

Originally Posted by solidONE

I'm on my 4th revision at the moment. Let me get my stuff in order and i'll post up. All the stuff is on my laptop, since romraider stopped working on my windows XP desktop for some reason. I tried setting it to peak loads seen at each rpm field below 4000 and that didn't go very well haha.

might be the jave version

[solidONE]

Originally Posted by steve99

might be the jave version

Oh... so I should update java?

[steve99]

Originally Posted by solidONE

Oh... so I should update java?

its more likey java auto updated and the new version is not compatable with romraoder or win xp.

if your not on latest romraider version might be worth trying the latest update.

[solidONE]

Originally Posted by steve99

its more likey java auto updated and the new version is not compatable with romraoder or win xp.

if your not on latest romraider version might be worth trying the latest update.

My desk top is a bit dated, but I give it a shot.

[solidONE]

I was staring at the load limit tables and looked at my log and thought what use is all the load limits from 800rpm to 2000rpm if they're just going to be the same exact value? Why not rescale like we do the MAF scale to get some more resolution in the problem areas so we can hit more of the peaks and the valleys seen in the engine load or afr?

I plotted out the peaks and the valleys of the afr "trouble areas" in my log:
http://datazap.me/u/solidone/plm85g-...2094-2091-2115

And came up with this:


The top is the current table, the bottom is a rescale to roughly where I plotted out afr changes on the log. I've not applied the changes. I would like to know what you guys think. If anybody has tried this it would be wayno, or steve99 or td or kodename47 or vgi on these forums.

[freerunner]

I've tried this one time actually. I was running one of Wayno's stg2 maps at this point of time. The first log after the 'rescale' was horrible. Open-loop was completely off (the ecu didn't get enough time to apply corrections from CL, I think)

I changed my mind and decided to do a custom maf scaling first. In the hope that ECU learning time will be much shorter.

This is the result so far. I'm definitely going to finish the last AFR offsets with an x axis rescale when there's spare time left.

[jvincent]

Originally Posted by solidONE

The top is the current table, the bottom is a rescale to roughly where I plotted out afr changes on the log. I've not applied the changes. I would like to know what you guys think. If anybody has tried this it would be wayno, or steve99 or td or kodename47 or vgi on these forums.

Just curious why you would want to try to use load limits to smooth out the AFR here instead of improving the granularity of the MAF scale in those areas?

What does your MAF scale look like in that region?

I'm going to guess that at the point where your AFR peaks to 14.59 you are just to the right of one of the defined MAF voltage values so it is interpolating based on the previous point and the next one and because the next point is far enough away the interpolation error is large.

I'm messing around with exactly this right now and have an adjusted MAF scale which uses more points in the 2.5 to 3V range which is the most problematic. Just waiting for my trims to finish learning before I log it.

[Wayno]

Originally Posted by solidONE

I was staring at the load limit tables and looked at my log and thought what use is all the load limits from 800rpm to 2000rpm if they're just going to be the same exact value? Why not rescale like we do the MAF scale to get some more resolution in the problem areas so we can hit more of the peaks and the valleys seen in the engine load or afr?

I plotted out the peaks and the valleys of the afr "trouble areas" in my log:
http://datazap.me/u/solidone/plm85g-...2094-2091-2115

And came up with this:


The top is the current table, the bottom is a rescale to roughly where I plotted out afr changes on the log. I've not applied the changes. I would like to know what you guys think. If anybody has tried this it would be wayno, or steve99 or td or kodename47 or vgi on these forums.

Yes, I've done it as i said in the other thread somewhere and the extra complexity wasn't worth it, especially when you start working on other setups you only want to be adjusting one, sometimes two points maximum. The AFR's only have to be within the ballpark so you can end up with a maf scale that's smoother than it otherwise would be. As soon as you do a pull in 2nd instead of 3rd or whatever, your perfect table you worked hours on will be no longer perfect.

[KoolBRZ]

I'm also working with Load Limit Tables with my "Ultimate" AVCS ESC tune. I tried using Wayno's 98 octane MT Requested Torque B table, (RTBt) and Load Limit Tables, (LLt) and it was a complete snooze. Like grandma just took her medication and went for a Sunday drive. My tune with the AT RTBt and LLts will literally peel rubber from a standing start, in an AT! The exact same tune with only RTBt and LLts changed to MT version was completely changed. So, I figured maybe it's the LLts and maybe it's the RTBt. I made tunes with AT RTBt and MT LLts, MT RTBt and MT LLts, MT RTBt and AT LLts, and I'm trying them out today. See pic for comparison. I'll let you know what I find out.

[solidONE]

Originally Posted by freerunner

I've tried this one time actually. I was running one of Wayno's stg2 maps at this point of time. The first log after the 'rescale' was horrible. Open-loop was completely off (the ecu didn't get enough time to apply corrections from CL, I think)

I changed my mind and decided to do a custom maf scaling first. In the hope that ECU learning time will be much shorter.

This is the result so far. I'm definitely going to finish the last AFR offsets with an x axis rescale when there's spare time left.

Good shit! I think I've already spent much more time than I need to on just these 2 tables. I did the same thing while learning how to adjust the maf scale when the OFT first came out. I think the best way to learn what the effect are is to just fiddle with it, being conservative at the beginning and go form there so you don't blow your engine up. lol

Originally Posted by jvincent

Just curious why you would want to try to use load limits to smooth out the AFR here instead of improving the granularity of the MAF scale in those areas?

What does your MAF scale look like in that region?

I'm going to guess that at the point where your AFR peaks to 14.59 you are just to the right of one of the defined MAF voltage values so it is interpolating based on the previous point and the next one and because the next point is far enough away the interpolation error is large.

I'm messing around with exactly this right now and have an adjusted MAF scale which uses more points in the 2.5 to 3V range which is the most problematic. Just waiting for my trims to finish learning before I log it.

My MAF scale is quite smooth all the way through. Aside from fuel trims while idling, it's pretty damn good, if I do say so myself. I wouldn't say it's flawless, but it's pretty damn near flawless in CL.

http://datazap.me/u/solidone/plm85g-...og=1&data=1-10

I said +-3% earlier, but under average IAT's and ambient temps (aside from idle speeds) LTFT is closer to +- 1~2% in terms of accuracy. I've probably spent as much time as wayno or any of these other guys on learning and tweaking the MAF scale for different NA setups. This load limit table is like a new "toy" within a toy to play with. lol I will have to double check what the MAF scale look like at the AFR spike. Thanks for the heads up @jvincent

Originally Posted by Wayno

Yes, I've done it as i said in the other thread somewhere and the extra complexity wasn't worth it, especially when you start working on other setups you only want to be adjusting one, sometimes two points maximum. The AFR's only have to be within the ballpark so you can end up with a maf scale that's smoother than it otherwise would be. As soon as you do a pull in 2nd instead of 3rd or whatever, your perfect table you worked hours on will be no longer perfect.

I had a feeling this was going to be the case. I'm nearly out of E85 anyways. I suppose I will revert back to the second revision and call it a day. Thanks for the help!

[solidONE]

Originally Posted by KoolBRZ

I'm also working with Load Limit Tables with my "Ultimate" AVCS ESC tune. I tried using Wayno's 98 octane MT Requested Torque B table, (RTBt) and Load Limit Tables, (LLt) and it was a complete snooze. Like grandma just took her medication and went for a Sunday drive. My tune with the AT RTBt and LLts will literally peel rubber from a standing start, in an AT! The exact same tune with only RTBt and LLts changed to MT version was completely changed. So, I figured maybe it's the LLts and maybe it's the RTBt. I made tunes with AT RTBt and MT LLts, MT RTBt and MT LLts, MT RTBt and AT LLts, and I'm trying them out today. See pic for comparison. I'll let you know what I find out.

Love the enthusiasm. lol :highfive: