2016 Supercharged Mustang leaning in top end

[4wheelinls1]

I have not been able to get the Supercharged Mustang to correct the AFR's as it should. Logging fuel pressure shows a drop in pressure from 60 down to 50 psi as I do a pull on the dyno. I have adjusted 43012 Inferred rail pressure vs fuel flow to feflect this and the AFR still goes lean. There is sufficient fuel as I can command a richer mixture and get the desired measured AFR. When I look at the logs it appears to me Commanded AFR and WB EQ ratio are back to front (incorrectly labelled). My external AFR sensor shows what equivalence ratio commanded is doing not the WB EQ. I treid playing with the O2 closed loop bias but there was no change. The car has a CAT back.

[SultanHassanMasTuning]

do you have a boost a pump

[4wheelinls1]

do you have a boost a pump

No I don't however I can get the mixture richer by commanding a richer mixture. I was expecting that the injector duty would compensate with the rescalled rail pressure vs flow. I just get no result from changing it. The fuel pressure does drop 10 psi but injector duty is still Ok.

[rshoe09]

ive found around 630-650hp the pump will taper off pressure rather quickly. if your having low fuel pressure issues I would suspect the pump isn't up to the task

[4wheelinls1]

ive found around 630-650hp the pump will taper off pressure rather quickly. if your having low fuel pressure issues I would suspect the pump isn't up to the task

Which I get but am wondering why the compensation isn't working as it should. The pressure drop is modelled relative to flow, I logged flow and backfilled the new pressure data, it should correct itself I would have thought, especially if I can command richer and get the result.

[rshoe09]

what is the power adder, what injectors and how much boost. what fuel.
and post the file so we I can see whats going on please

[4wheelinls1]

what is the power adder, what injectors and how much boost. what fuel.
and post the file so we I can see whats going on please

I have attached the dyno log of fuel pressure, boost etc. This is not the same run as the HP log in the origional post. The vehicle is a PD supercharger with ID1000 injectors. I have commanded increasingly richer WOT mixture to stop the lean out. You can see the scaling and changed values in the Fuel Sys Inferred rail pressure tab, I have tried overcorrecting with no result. Certaily in GM LSA world where the vehicle has a fuel pressure sensor the injection duty compensates for fuel pressure, they too drop with increased output/flow. I'm wondering why the injection model doesn't seem to work on the Mustang as I have logged the actual fuel pressure at the rail and made the appropriate change to the inferred rail pressure vs flow. I did this by logging fuel flow and fuel pressure from the dyno.
I know the pressure/flow can be bumped up with a booster and that will remedy the issue however there is clearly still sufficient fuel as with a richer commanded it doesn't lean out. I'd have thought the Inferred rail pressure would compensate in the injector duty but it appears not. Trying to avoid additional cost of booster when there is sufficient fuel whilst maintaining the correct tune and actually delivering the commanded fuel.

Cheers

[Jn2]

Just have them install a BAP. This could be related to how the stock ECM handles fueling, there is a low and high speed. I believe you commanding a richer lambda to only achieve the lambda you are desiring is a bandaid fix. A BAP should keep rail pressure consistent though the pull like you are hoping to have it. VMP sells a plug and play BAP for like $300 brand new

vvvvvv after reviewing your log vvvvvvvv

Your Throttle source was "Torque Control" during the entire WOT pull. That is one thing I would look into.

At the beginning of the pull, which was 2000rpm, you were commanding .86λ but were getting .90λ instead(running lean). It wasn't until 4,200rpm, where you were commanding .80λ and the car was seeing .81λ.

From 4200 and up you commanded .85λ but were actually getting .80λ(running rich), around 6,000rpm it commanded .87λ and ran .83λ(still running rich). Overall though that is pretty lean for a supercharged car, especially since your commanded lambda table from above shows you were wanting to run .79λ and richen down to .76λ

Can you go back and log LTFT and STFT so we can get a better picture of what the ECM is doing, bc everything i pointed out above is almost opposite. If you were out of fuel you would be running leaner than commanded, not richer, your first half of the pull the car was running way leaner than commanded, than around the middle it flipped and started to run way richer than commanded.

Posting your tune file would also help a lot. What is your Fuel enrichment rate set to? if you have it on the stock .050 setting you may want to give that a bump up to ".100" , that may help the car richen up faster when you go WOT.

[4wheelinls1]

Just have them install a BAP. This could be related to how the stock ECM handles fueling, there is a low and high speed. I believe you commanding a richer lambda to only achieve the lambda you are desiring is a bandaid fix. A BAP should keep rail pressure consistent though the pull like you are hoping to have it. VMP sells a plug and play BAP for like $300 brand new

vvvvvv after reviewing your log vvvvvvvv

Your Throttle source was "Torque Control" during the entire WOT pull. That is one thing I would look into.

At the beginning of the pull, which was 2000rpm, you were commanding .86λ but were getting .90λ instead(running lean). It wasn't until 4,200rpm, where you were commanding .80λ and the car was seeing .81λ.

From 4200 and up you commanded .85λ but were actually getting .80λ(running rich), around 6,000rpm it commanded .87λ and ran .83λ(still running rich). Overall though that is pretty lean for a supercharged car, especially since your commanded lambda table from above shows you were wanting to run .79λ and richen down to .76λ

Can you go back and log LTFT and STFT so we can get a better picture of what the ECM is doing, bc everything i pointed out above is almost opposite. If you were out of fuel you would be running leaner than commanded, not richer, your first half of the pull the car was running way leaner than commanded, than around the middle it flipped and started to run way richer than commanded.

Posting your tune file would also help a lot. What is your Fuel enrichment rate set to? if you have it on the stock .050 setting you may want to give that a bump up to ".100" , that may help the car richen up faster when you go WOT.

Hi, I appreciate the feedback, the log is an older one and the Torque source issue no longer exists, I have also adjusted the O2 bias so the widebands in the car more closely reflect the dyno wideband. I set the enrichment rate at 1.0 in all these applications, the vehicle O2 log does not match the external log very accuratly, the dyno log CSV file is what I am baseing my judgement on. I will get some logs tomorrow that are more up to date and where the dyno data is the same run as the vehicle log. I would normally turn off LTFT while tuning. I know I am not out of fuel as I can still command and acheive richer mixtures, I just can't acheive richer mixture by changing the inferred rail pressure as I would have expected(hoped) as I know I am getting a pressure drop. The difference between what I am commanding in the software and the commanded EQ in the log is odd as well as the vehicles WB is possibly part of the issue, as you said the trims are negative in a lean situation, I'd have expected they would be positive, adding fuel. I can't see any other fuel modifiers, cat overtemp, flange temp is all off. I haven't seen anything in SCT either that may not yet be in HP.

Cheers

[Dohctor]

Does the car have long tubes? I've had this problem when I didn't have the 02 sensors calibrated for the new position of the sensors. I have 2 coyotes in my shop right now making 700+ rwhp without boost-a- Pumps so the fuel systems are usually pretty stout.

[15PSI]

Kenne Bell did a fuel pump test of many different brands of fuel pumps back in 2013. When they mounted a stock Coyote fuel pump on their custom pump dyno, their tests indicated that the OEM Coyote fuel pump will support around 750 RWHP without a BAP. Running the pump up to 21 Volts with a good BAP, the coyote pump was good for over 900 RWHP. Follow this link:

http://www.mustangandfords.com/how-t...ump-flow-test/

[Dohctor]

That has been my experience, however, the 15+ coyotes tend to lean out around 720. Either way if the temp loss from valve to 02 is not calibrated you end up with wonky fuel trims that look like what we have here.

[4wheelinls1]

After maxing the O2 Bias towards rich I am happy with the result, there is 0.2 lambda discrepency between my dyno log and the cars sensors but I have seen that often with different brands of WB. The trims are very close, pulling a little fuel but it all makes sence and is stable and repeatable. I was hoping that with the Inferred rail pressure would increase injector duty with dropping pressure similar to the LSA which uses a fuel pressure sensor, looks like stage 2 involves a booster pump. Now for the other problems.

[Adrianc12393]

did it end up being the 02 sensors on the new position of the long tubes? I have a 2016 coyote also Paxton supercharged with a vmp bap , id1000 and rail pressure isn't rising more then 52lbs, going lean at 6000rpms cant figure it out , I also have 1 7/8 bbk long tube headers , or if u wanna share a data log or tune would appreciate it to compare

[4wheelinls1]

I scaled the O2 sensors and trimmed the MAF it hits the targets fine up to about 650hp, have just fitted a booster pump with the pan to go E85, the booster pump made no difference to the mixture at this power level. I f you log the fuel pressure at the rail it does drop as do all with rear regulator and non-return. I did find the car sensors do read a little leaner than the dyno.

[Adrianc12393]

I scaled the O2 sensors and trimmed the MAF it hits the targets fine up to about 650hp, have just fitted a booster pump with the pan to go E85, the booster pump made no difference to the mixture at this power level. I f you log the fuel pressure at the rail it does drop as do all with rear regulator and non-return. I did find the car sensors do read a little leaner than the dyno.

Oh ok thanks for the Info