jcorenman

Thanks. Was this done with the same fuel map that was shown in Victor's post #6? Or a later map?

In your video last night, it looked like the area that was unstable was MAF around 80-90, RPM's around 2000-2200. Is that correct, and was that the case here also?

What is confusing here is that the map looks lean in the area of interest, 2000 & 2400 RPM columns, and 84-132 load. But it doesn't look that way in the plot that Victor posted last night (post# 26). Was this the same map or different? Engine not completely warmed up here, or then? Stuck in traffic with high intake-air temps? Something is different, causing inconsistent results, but we've only got small pieces of the data here.

The AFR's here were not actually lean because O2-adjust was busy compensating for the map errors. But without O2-adjust being enabled, AFR's would have been in the 16-ish range in that part of the map. At higher RPM's and/or higher loads it looks OK.

Here's what I get with Sharkplotter. No bin file or maps, so we are only looking at fueling vs. ideal.
This is the normal Sharkplotter view: O2-adjust is enabled, so SP is showing "what would have been" if O2-adjust had not been active.



This logging, and the video last night, were done with O2-adjust active. What happens if you disable it? You will need to re-tune at least that part of the fuel map (which should be done with O2-adjust disabled, in any event).
Once that is done, leave O2-adjust disabled for a while and see if the surging and unstable idle is any different. When O2-adjust is active it is messing with AFR, up and down a few percent (half an AFR unit or so), which is one reason that the idle is not rock-steady.

Cheers, Jim

jeff spahn

Jim
The run to work this morning I thought was with O2 disabled. I clicked the disable button on the sharktuner and reset the values. I then drove to work. I took the file I created this morning and put it in Sharkplotter. I adjusted the fuel map by opening tools and clicking adjust map. I then viewed it and copied and pasted the map to the sharktuner on my car.

I will drive home with the newly adjusted map, I'll turn off (or ensure it is off) the O2 sensor and reset the values.

Let's see what kind of results come out of that. I'll do two or three logged runs and post them in the folder again.

I am having difficulty understanding the Open Project function of the Sharkplotter, even after reading the directions several times. It doesnt click somehow. I searched YouTube for Sharkplotter videos but couldn't find anything. Perhaps I could call you.

victor25

Jeff
I think you have adaptation turned off and reset. I believe what Jim is talking about is forced non cat mode. But you have to make sure that both maps match before you do this!!!
Its easier to just use the "open log file" in sharkplotter, verses the project function until you get that.

Jim
We are having nice fall weather in the Midwest over the last few days. Mornings in the 50's and 70's in the afternoon. Here is the plot with recommended adjustments just like yesterday. I am guessing that the cool morning drive was full of clean fresh O2, and thats the difference between yesterday and this morning. I think adding little fuel where you circled today and where I circled yesterday will help smooth things out, but it's not necessarily the answer.
Question... do you think that running the car on a simulated NB from a WB could or would cause any issues? Is there any delay when going this route?
Also, with the injectors being set to 30#, what would you recommend the acceleration enrichment be set at? Stock is something like 400/300/200/100. His I believe his is 200/150/100. Thoughts?

jcorenman

There are two different adjustment mechanisms: "O2-adjust" is the short-term adjustment that is made continuously when the engine is running, based on the O2-sensor reading-- either the factory narrow-band O2 sensor, or the NB-sim signal from the WBO2 controller. "O2-adjust" can be logged and can be used for tuning, but you will get more consistent results by disabling it for tuning/testing.

"O2-adaptation" is the longer-term compensation, which is updated slowly and is stored when the engine is shut off. This is added to the whole map, and needs to be disabled and reset for tuning. Disabling O2-adjust does not disable the O2-sensor, or O2-adjust.

O2-adjust was definitely enabled for your video last night, and logging this AM-- it was shown on the fuel-monitor page, and in the data logs.

To disable O2-adjust either disconnect the factory O2-sensor (or the NBsim signal), or copy the "cat" fuel map to the "No-cat" map and then select "Force No-cat mode". Also, the new Sharktuner ver 6.3 has a "disable O2-adjust" option in the fuel-parameter page.

Makes sense, but you might want to do one more logging and SP cycle with O2-adjust disabled. I don't know if this is related to the surging issue but getting a smoother AFR across the map, without O2-adjust, is a good place to start.

Sharktuner's log files are named "Run1.txt", etc-- if you change the log file-name then leave the word "Run" as part of the name, SP is looking for that. I renamed your file as "Run_92713am30lbnoo2.txt" so that SP's project manager could find it. And I am around most of today if you want to call.

Cheers, Jim

jcorenman

Victor,

We overlapped replies, I think we are on the same page.

Correct, disable O2-adjust for tuning (in addition to O2-adaptation. As I mentioned there are different options for disabling O2-adjust, but using the "force no-cat "mode does require that the cat map be copied also into the no-cat map for tuning.

Agreed, and your plot above matches what I get. But I would be more confident if it was done with O2-adjust disabled.

In theory there is no difference between NBsim and a narrow-band O2-sensor. But "theory" and "reality" are two very different places, sometimes. I don't think that is the issue here, however.

I think it was 400/50/0/0 if I remember the video correctly. That seems short. I think my approach would be to leave the enrichment settings at the stock values until the basic mixture was correct, then adjust as needed. The "base" number is the amount of extra fuel (above/below the normal enrichment), and the next four numbers control how long the enrichment lasts. This is strictly a transient-response adjustment (along with the EZK's timing-retard on transients), but other than some seat-of-pants tweaking (and fiddling with accelerator-pumps in the "old days") I don't have much experience here.

FredR

Jim,

Maybe your driving experience is different to mine but to be clear, what I am saying is that having monitored what happens in ST2 when driving, one tends to be in cruise [part throttle] mode over that range of cells listed up to about 4k rpm or so but once you work the motor past 4k it tends to go into the WOT type operation [or close to it] thus why it seems to make perfect sense to zero the WOT throttle map and simply tune AFR based on load in the cruise map. Load values under 100 or so only seem to happen when you are off throttle or rolling down a hill with little to no load at all. Thus if one focuses effort on the cells I listed you do not seem to get too many drivability issues as I can tell.

It might be interesting to see how much one can lean off the lighter load cells for economisation but I have never been tempted given our gasoline prices.

Regards

Fred

victor25

I set them lower because of the larger injector. 400% on a 19# is one thing, but 400% on a 36# injector is twice the fuel. Unless the LH/program/PEM is compensating for the larger injector already?? I am running 60's in my car and have it at 150/125/100. The response is good, but still not as crisp as I would like

jeff spahn

We are going to try introducing a 3.5" honeycomb MAF air straightener to see what effect that has on the idle and mid cruising range.

Tony

I had mild surging on my car and a modified "apple slicer" from target fixed a surging issue i had from day 1. The surging was very mild but definitely there...its gone 100% now.

AO

Not sure how well that would work given the difference in SCer placement relative to the MAF.

Bill Ball

In one car in which I installed a Murph kit I observed surging or hunting idle, as Jeff just added to his report. Others did not. I attributed it to an abrupt change in direction and cross section of the intake tube right above the MAF. I changed that section temporarily and the problem disappeared. I don't know if this is an issue with the current system or not, but some kind of straightener, be it Tony's apple cutter or something else is worth a try.

So, does the surging cruise issue continue despite all the fuel map reviews that seem to indicate fueling is correct and there is no lean surge?

I've always questioned "smoothing". The stock maps have all kinds of wide variations cell-to-cell and cruise stability is not an issue.

Also, regarding zero WOT values...With George Suennen's car we have ended up very rich at 180 to 210 MPH despite zero WOT numbers. The problem is that we cannot tune the main map for those speeds unless we tune real-time during the race itself. We had actually prepared ourselves to do that in one race when it was cancelled. Maybe that was just as well. Trying to click on and alter cell values at those speeds could have created some problems, but just the fact that the opportunity was there with John Speake's Sharktuner is rather amazing. Maybe I should have just hit "Autotune", eh, John? I suppose we should have been able to get close enough holding 5800-6000 RPM (the high speed cruise RPMs) in 3rd gear on the dyno, but it didn't work and 4th gear at those RPMs would overspin the dyno.

Tony

I wasn't sure of his exact set up..if its stock i would just make sure the screens are installed.

SeanR

Anyone else found that "disabling" 02 adaptation makes the car run better? I'm back to ground zero on my car and feel like I've never touched this thing.......

victor25

Absolutely! I actually leave mine off permanently now. Mine works well for a while, but then goes haywire and screws wverything up untill I reset it.

SeanR

Glad I'm not the only one......