15+ Mustang Flex Fuel spark tables missing?

[tramotorsports]

Attempting to enable flex fuel on a 16+ Mustang; I notice I don't have any tables for Flex Fuel Spark Modifier or Flex Fuel Spark Multiplier. Spark Blending vs. Ethanol Content is available though. What am I missing here????

[murfie]

I dont think the 2015+ have those tables. Not sure if they ever will.

Did you see the FF TQ multiplier?

TQxFF.PNG

How it looks in a f150 FF tune. 65% E adds 3% calculated torque torque. This should have an effect on spark.

The other option is to use the learned octane adjustment so you can set the borderline tables up for a high E% timing then when you go back to 93 have it learn to pull timing from the octane adjustment table.

[Bugasu]

If you think something is missing, I think the fastest way to get it addressed would be to contact support

[tbrtuning]

I would love a separate IAT multiplier or modifier of some type also if it were available.

[curt@injected]

There are no spark tables for alcohol in the 15+ mustangs.

[4wheelinls1]

I'd have though there is an alcohol spark table missing given there is a blend table 21327. Must be blending from something.

[Eric@HPTuners]

The 2015+ F-150 5.0L has tables to deal with Ethanol, the Mustang does not. Compiled out.

[4wheelinls1]

The 2015+ F-150 5.0L has tables to deal with Ethanol, the Mustang does not. Compiled out.

What does the Blend table in the spark tab refer to?

[tbrtuning]

So have you guys found that the Mustangs learn octane adjustment quickly enough to be comfortable running timing for E85 and letting this table be a modifier for them to learn down on lower octane fuels that cannot take the timing?

I'm scared to do this unless some very experienced guys say that it's safe. I'm talking about on bolt on NA cars only and not boosted cars also.

[4wheelinls1]

The car can add up to 10 degrees advance while in borderline knock mode. If the sensors calibrition is correct it should add timing without cal changes.

[murfie]

So my problem with relying on the knock sensor to add timing when running E85 or any fuel, is the ecu wont add timing fast enough and a noticeable performance decrease will occur. Stock its 1* every four seconds. If you meet all the conditions, not just knock activity, it can be as fast as 1* every two seconds. that means to get the full 10* advance you would need to be accelerating with out knock activity for 40 seconds at most and at least 20 seconds on a very rare good pull. Drag strip, Dyno, or Street driving that delay of the timing not there will be noticeable. Sure you can turn this rate up and have it add timing faster and even vary how fast it adds based on RPM(faster for the low rpms and slower as they get higher), but then you risk the intensity of the knock going up when it does sense knock and it pulling even more timing or not pulling the timing soon enough and having a bad day. Also know that once knock starts it takes more timing pulled to stop it than it would have to just to be a bit more conservative and not caused it in the first place. Because thats true tuning borderline tables so total timing is not dependant on these rates as much and slowing these rates down adds performance by having the ignition more readily available and not passing the actual borderline as far.

The reason I suggest the octane adjustment for E85 timing is because E85 has a higher octane rating than 93. The Ecu can easily learn this from the knock sensor activity just as it learns AFR from the Lambda sensors. Rather than relying on the knock sensor to add the timing slowly and running into knock most pulls, I would rather have the ECU try the higher number timing and sense the knock and learn it if it's there and quickly settling the timing and discontinue using the knock sensors. If its not there, there is no waiting for the timing to be added every time you accelerate. If it learns to pull some timing even with E85 for what ever reason, then the knock advance can make up for that when needed, which will be much less than trying to make up for the entire difference from 93 timing and E85 timing.

Both ways use the knock sensors and will possibly get you higher timing. One uses them all the time and the other has the ECU learn patterns and stops relying on them as much. I think if you trust the ECU to learn fuel trims and adjust AFR then trusting it to learn octane and adjust timing is not much different. I find most people are happy if they see knock advance in the negatives. If your advance is at -4 and it goes to -2 that was a positive knock adjustment meaning knock was detected and timing reduced. Then when that happens it will be another 8 seconds or more before you get back to -4* knock advance if the knock event wasn't to intense and the reduction stopped it. What i'm saying is 0* to 2* knock is the same as -4* to -2* knock advance so treat them the same.

[4wheelinls1]

So my problem with relying on the knock sensor to add timing when running E85 or any fuel, is the ecu wont add timing fast enough and a noticeable performance decrease will occur. Stock its 1* every four seconds. If you meet all the conditions, not just knock activity, it can be as fast as 1* every two seconds. that means to get the full 10* advance you would need to be accelerating with out knock activity for 40 seconds at most and at least 20 seconds on a very rare good pull. Drag strip, Dyno, or Street driving that delay of the timing not there will be noticeable. Sure you can turn this rate up and have it add timing faster and even vary how fast it adds based on RPM(faster for the low rpms and slower as they get higher), but then you risk the intensity of the knock going up when it does sense knock and it pulling even more timing or not pulling the timing soon enough and having a bad day. Also know that once knock starts it takes more timing pulled to stop it than it would have to just to be a bit more conservative and not caused it in the first place. Because thats true tuning borderline tables so total timing is not dependant on these rates as much and slowing these rates down adds performance by having the ignition more readily available and not passing the actual borderline as far.

The reason I suggest the octane adjustment for E85 timing is because E85 has a higher octane rating than 93. The Ecu can easily learn this from the knock sensor activity just as it learns AFR from the Lambda sensors. Rather than relying on the knock sensor to add the timing slowly and running into knock most pulls, I would rather have the ECU try the higher number timing and sense the knock and learn it if it's there and quickly settling the timing and discontinue using the knock sensors. If its not there, there is no waiting for the timing to be added every time you accelerate. If it learns to pull some timing even with E85 for what ever reason, then the knock advance can make up for that when needed, which will be much less than trying to make up for the entire difference from 93 timing and E85 timing.

Both ways use the knock sensors and will possibly get you higher timing. One uses them all the time and the other has the ECU learn patterns and stops relying on them as much. I think if you trust the ECU to learn fuel trims and adjust AFR then trusting it to learn octane and adjust timing is not much different. I find most people are happy if they see knock advance in the negatives. If your advance is at -4 and it goes to -2 that was a positive knock adjustment meaning knock was detected and timing reduced. Then when that happens it will be another 8 seconds or more before you get back to -4* knock advance if the knock event wasn't to intense and the reduction stopped it. What i'm saying is 0* to 2* knock is the same as -4* to -2* knock advance so treat them the same.

Yep I agree, I'm more concerned about how fast timing can come back out when you go back to 98 to be honest, the system is not dissimilar to the octane scalar used by GM or Subaru and Mitsubishi. I am concerned that if a customer was to fill with PULP after driving on E85 and not be respectful and give the system time to adapt that there could be some quite severe knock. I limit my tunes to allowing only 2 degrees knock advance and get the Borderline table as close as possible, I have to make significant changes to the knock sensor sensitivity using knock ears due to the mechanical noise of a PD blower and the cast alloy manifold that tends to show significant false knock after the mechanical change.

[murfie]

Knock sensors pull timing quickly. As fast as they hear it and pull as much timing based on intensity. The ECU will learn where it knocks at low RPM low load and adjust octane quickly as FF adapts. Its an engine safety thing. Timing is pulled out across the entire table based on octane not just spots.

If customer isn't allowing AFR time to adapt and mature thats just as bad. If they have an Ngauge or other way of monitoring, as they should to monitor these features, have them watch octane rating and AFR mature for values you tuned it to for.

[tbrtuning]

Thank you Murfie. I've been zeroing out the octane adjustment and taking a somewhat conservative approach on spark letting a good be be added. I will experiment on my friends car with allowing octane adjustment and setting base spark closer to where I want it.

[murfie]

Yes experiment. Get a 93 borderline table, then establish a borderline table for something like E-45 or E-50. Take the difference and put it in the octane learn table. This will split it into lower e% and higher e% and give you a "blend."

Ideally you would want spark modifier to blend in more as % rises, but if you don't have access to that this works better than just the advance alone.

[4wheelinls1]

Yes experiment. Get a 93 borderline table, then establish a borderline table for something like E-45 or E-50. Take the difference and put it in the octane learn table. This will split it into lower e% and higher e% and give you a "blend."

Ideally you would want spark modifier to blend in more as % rises, but if you don't have access to that this works better than just the advance alone.

I look forward to trying this when we play with E85 in the next coming months. Good info. Thanks

[metroplex]

What does the Blend table in the spark tab refer to?

I would like to know as well. It shows a value of 1.00 for alcohol composition of 65% or more, so what does this 1.00 really do?

I have a 2007 S197 GT that is running E85, and I'm trying to squeeze every MPG out of it. Is there value in multiplying the Torque / Inverse Torque tables by 1.03 with E85?

[murfie]

It allows the flex fuel spark tables to be blended in to the borderline tables, in a way other than linear with the inferred alcohol percentage.

The 15+ do not have these spark modifier tables. I suppose it could refer to the alcohol TQ modifier tables blending. Increasing the torque values with the modifier will effect the borderline and MBT ignition relationship by bringing them closer together and increasing MBT advance just as alcohol actually does for the engine.

[metroplex]

I found it in a 2016 F150 5.0 file. So how is BKT modified by the blend factor of 1.0?

[murfie]

In the ecus there are bkt flex fuel modifiers. At 65% being 1.0 that means the 100% of the modifier is applied at 65%. This brings the spark in quicker than 100% only at 85% or what ever afr the end point is set to.