2012 Mustang GT Ford Racing 2.3 SC Surging

Good morning guys,

I am hoping someone can help me point out the problem or obvious that I am missing or a solution to my issues. I am tuning this 2012 Mustang GT that has a Ford Racing 2.3L Whipple supercharger, 14psi pulley, 1000cc injectors, twin 65mm TB, 127mm JLT intake, long tubes, exhaust, on E70. It is an auto car with a 2B converter, 3.15 gear. I am dealing with some massive surging around .6 load and up to right before WOT with about 25% throttle and up. I have read through multiple threads discussing the surging I believe I am having. I have the exact throttle data, even tried several different ones to see if it helps. I have recalculated my torque calculations and inverse. Tried the recommended paths to take in correcting this with the torque calculations and or throttle data adjustments, still no luck. I am pretty much at a loss at this point. I have attached the calibration and log of what it is doing, any help would be greatly appreciated.

Kris

Bump!

You need to go through and adjust your spark tables. Timing is cruising at 30* and slams into a wall out of no where and drops to 21. The Knock sensors are useful. If the car is adding 8 degrees in the same area, it's safe to increase the correct cells and spark tables so it's only adding 4 instead of 8. The change in timing which is part of a huge calulation will be noticeable when driving but is not the cause of your surge.

Airflow > General > Tip in disable it. You may also need to disable it in your torque ratio tables, or adjust the ratio.

Look at this pattern, this happens twice. You begin picking up speed, knock sensors add 8 degrees and the wall. Important valve events should be happening and they're not. IVO never advances. Check over your distance tables. You may want to enable a mapped point with more intake advance and disable 9.
Attachment 92039

The main cause of the surge, Scheduled Torque should not be surpassed by engine brake torque or etc torque request. Scheduled torque should be the highest, it is the calculated torque if DA, weather, if nothing effected the way our cars ran. Your torque tables need recalculated. You want the torque tables to be a close resemblance to actual power. Adjusting torque/inverse will change schedule torque, engine brake torque, air load, MAF lbs, since airflow is altered through these tables, it effects the throttle body and how it measure area, angle, driver demand, torque resulting in surging and jerky throttle.
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I'd decrease the values at high loads in the torque tables. I just noticed the torque tables have the same values. The tables should not be the same. Advancing the intake changes cylinder conditions, everything is changed. Power is increased, power is being measured and calculated all the same and it shouldn't.

Thank you for the response. Since my post I have tried a few different adjustments, some reflecting what you stated, some not, with not much luck. I have a new course of action I will attempt in the next day or so, I will post my findings.

Kris

I'm assuming from E70, this is a return style fuel system. Many times the data for both injectors and rail pressure in the calibration isn't setup to match how the fuel system is installed and functions. Causes many people to chase their tails trying to correct it in other parts of the calibration.

Quote:

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Originally Posted by murfie

I'm assuming from E70, this is a return style fuel system. Many times the data for both injectors and rail pressure in the calibration isn't setup to match how the fuel system is installed and functions. Causes many people to chase their tails trying to correct it in other parts of the calibration.

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this

Actually looking at this on my computer and not my phone I actually see the logs and cal.

Your SD is limiting the multiplier being used for your injector flow rate. If you MAP referenced your regulator you can eliminate the multiplier.

Attachment 92096

Attachment 92095

May have found the problem, will update after testing...

Kris

No go on the solution. What I stumbled upon is what was previously mentioned about the fuel system and being setup properly for a return. I did have the incorrect data in place for a return style, it was setup for stock style and at 55 psi base when the car is running 65 psi base. Unfortunately, changing that data changed absolutely nothing. Still surging in the same exact way. Log and calibration attached. I'm running out of ideas. I'm not sure if the problem is the scheduled torque dropping and causing the tip in detonation control to remove timing and close the throttle blade, or if the tip in detonation control is causing the drop in scheduled torque which is in turn dropping off timing and closing the throttle blade, definitely chasing my tail here. Next I am going to create histograms to review scheduled torque vs commanded torque at desired throttle plate positions vs rpm and load, see if I can get the issue to show it's ugly face.

Kris

Torque and inverse tables will be your solution.

Scheduled torque will always be the idle torque above commanded(40-70Ft lbs). You probably won't find anything there.

If fuel trims are with in 10% and not swinging wildly, I'm saying the throttle body is the issue. The electronics and ecu are not talking with each other correctly, or a physical issue which is giving bad blade control.

Quote:

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Originally Posted by murfie

Scheduled torque will always be the idle torque above commanded(40-70Ft lbs). You probably won't find anything there.

If fuel trims are with in 10% and not swinging wildly, I'm saying the throttle body is the issue. The electronics and ecu are not talking with each other correctly, or a physical issue which is giving bad blade control.

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I am going to review the torque tables just to be safe. It is possible it is throttle body related, I have tested multiple different data for the twin blade, with no luck. The owner has a big name tuner calibration he ran on it with no issues, we've tested personally. So it's not physical. The MAF curve/ fuel trims are very close, better than within 10%.

Kris

How do you have your regulator referencing? From those logs fuel trims are still terrible and swinging wildly. They poll in the log pretty slow and you can still see it on charts, look at your WB pids they poll faster.

You can always reference atmosphere set the regulator pressure to 55PSI and use the stock style injector data. Easiest way to eliminate problems there, and narrow it down to SD error.

To use ID data for return style, you need to set the base pressure to what it is at referencing atmosphere with the engine off, enter that value into their sheet. Then hook the reference up to the mainifold. If this was turbo or centri sometimes they get hooked up to the charge pipes or to a reference that gets blocked during boost and the regulator doesnt go higher than the "base" pressure. You would not use the return data in that case, but a hybrid of stock style and return style, very hard to get it accurate. The return data assumes MAP and rail pressure are in a 1:1 relationship always, when MAP goes up rail pressure does, when MAP goes down rail pressure does, and the injectors always flow a specific rate. It effectively makes error in the SD irrelevant, unless you are hitting a limit and getting the ETC over ridden. There's only one flow rate the injectors are going to do as the effective differential across them doesn't change. Using the stock style data with SD, it describes how the injector flow rate changes, if every thing is accurate, through the pressure-multipliers that are based on this differential.

Quote:

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Originally Posted by murfie

How do you have your regulator referencing? From those logs fuel trims are still terrible and swinging wildly. They poll in the log pretty slow and you can still see it on charts, look at your WB pids they poll faster.

You can always reference atmosphere set the regulator pressure to 55PSI and use the stock style injector data. Easiest way to eliminate problems there, and narrow it down to SD error.

To use ID data for return style, you need to set the base pressure to what it is at referencing atmosphere with the engine off, enter that value into their sheet. Then hook the reference up to the mainifold. If this was turbo or centri sometimes they get hooked up to the charge pipes or to a reference that gets blocked during boost and the regulator doesnt go higher than the "base" pressure. You would not use the return data in that case, but a hybrid of stock style and return style, very hard to get it accurate. The return data assumes MAP and rail pressure are in a 1:1 relationship always, when MAP goes up rail pressure does, when MAP goes down rail pressure does, and the injectors always flow a specific rate. It effectively makes error in the SD irrelevant, unless you are hitting a limit and getting the ETC over ridden. There's only one flow rate the injectors are going to do as the effective differential across them doesn't change. Using the stock style data with SD, it describes how the injector flow rate changes, if every thing is accurate, through the pressure-multipliers that are based on this differential.

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I wouldn't say SD error is irrelevant outside effective rail pressure calculation. It is also used to fill in transient MAF data which is pretty important in transient throttle conditions.

Quote:

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Originally Posted by murfie

How do you have your regulator referencing? From those logs fuel trims are still terrible and swinging wildly. They poll in the log pretty slow and you can still see it on charts, look at your WB pids they poll faster.

You can always reference atmosphere set the regulator pressure to 55PSI and use the stock style injector data. Easiest way to eliminate problems there, and narrow it down to SD error.

To use ID data for return style, you need to set the base pressure to what it is at referencing atmosphere with the engine off, enter that value into their sheet. Then hook the reference up to the mainifold. If this was turbo or centri sometimes they get hooked up to the charge pipes or to a reference that gets blocked during boost and the regulator doesnt go higher than the "base" pressure. You would not use the return data in that case, but a hybrid of stock style and return style, very hard to get it accurate. The return data assumes MAP and rail pressure are in a 1:1 relationship always, when MAP goes up rail pressure does, when MAP goes down rail pressure does, and the injectors always flow a specific rate. It effectively makes error in the SD irrelevant, unless you are hitting a limit and getting the ETC over ridden. There's only one flow rate the injectors are going to do as the effective differential across them doesn't change. Using the stock style data with SD, it describes how the injector flow rate changes, if every thing is accurate, through the pressure-multipliers that are based on this differential.

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The regulator is boost referenced at base pressure that is set at 65psi, referenced to stay static at 65psi. I have increased poll speed for the WB and the STFT and LTFTs to read more data. When the surging starts, the trims start to go off as well. I noticed this before, and adjusted MAF under the impression this was a possible culprit, however, it still swayed in large corrections of similar amount, even though large amounts were adjusted on the MAF.

I can disconnect the reference to atmosphere and set pressure to 55psi and use the stock style data, as you stated. If it is in fact an SD issue, that should reveal it correct? Correct me if I'm wrong, but I assume by SD, you mean speed density?

Kris

The trims swinging is more likely a result of the surge, not a cause of it IMO.

That's what I was thinking. Following the log, the throttle closure and timing advance disruption occurs before the trims start to go out of wack.

Kris

Just learning but I see throttle fluctuations MP4 and around 3000RPM a couple of times.
The calculated SD load is around 66% but logged load is around 52%, logged MAF 9.32 SD calc MAF 10.29

In a more stable part of your log, no throttle fluctuations MP3, 2366 RPM there is less difference between logged load and SD calculated load - 45.1% and 51.8%, logged MAF 7.14, SD calc MAF 6.90

I don't know if this is enough difference to matter but when I put 3" exhaust and long tubes on my car I had to change SD tables to get rid of surge and IPC error centered around 3000 RPM and loads 0.6 0.7 (torque tables didn't work). Mine was opposite though, I had to increase SD, yours looks like it needs decreased in that range.
I don't know as much as the guys who already posted but maybe your longtubes had effect like mine.

Quote:

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Originally Posted by GapRider

Just learning but I see throttle fluctuations MP4 and around 3000RPM a couple of times.
The calculated SD load is around 66% but logged load is around 52%, logged MAF 9.32 SD calc MAF 10.29

In a more stable part of your log, no throttle fluctuations MP3, 2366 RPM there is less difference between logged load and SD calculated load - 45.1% and 51.8%, logged MAF 7.14, SD calc MAF 6.90

I don't know if this is enough difference to matter but when I put 3" exhaust and long tubes on my car I had to change SD tables to get rid of surge and IPC error centered around 3000 RPM and loads 0.6 0.7 (torque tables didn't work). Mine was opposite though, I had to increase SD, yours looks like it needs decreased in that range.
I don't know as much as the guys who already posted but maybe your longtubes had effect like mine.

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When you say you adjusted the SD tables, you adjusted the offset, slope, and quandratic term for this? After reading this a couple of times, it got me thinking. I compared the load calculations and valve events at the currently targeted MPs for the current VCT scheduled mode in this area, and I can see what you mean, the calculated load is significantly lower and the valve events are targeted for "fuel economy" and low load scenarios. After reviewing the VCT positions at a separate MP with more advance from both sets of camshafts, the calculated load is much higher. I am going to alter the MP selection for this area and see if there is an improvement to get calculated load back on track as well as a possible improvement to the surging situation. I have tried A LOT to get this resolved, with no improvements. I am willing to try everything at this point.

Kris

Attachment 92405

give this a test