paxton mustang leans out in higher rpms

[askkmb]

Hey everyone, i am tuning a 2013 mustang with a paxton 2200 supercharger at 7 psi. My problem is that in the higher rpms my afr goes lean. I am shifting at 6800 rpm but it already starts to go lean at around 6000 rpm. I have a pretty nice 11.5 afr curve under 5800 rpm and then it starts to go lean to about 12.5 afr. I have added a lot of fuel in the maf period table in the area where the problem is and it doesn't seem to get any better. Fuel system consist of id1000 injectors, stock fuel lines/rails, stock pump with a vortech non-programmable fuel pump booster. Voltage going into the fpb is 14ish and exiting to the pump is 17.8ish volts. Would think this should be enough fuel as ive seen people making 800ish hp with same fuel system.

[Jggregory99]

Post tune and log..

[askkmb]

19. maf period.hpt This is the last file i made. Tune is still far from done but first need to get the afr sorted out. Also i already tried raising the inferred fuel pressure table and raised the max duty cycle value but still no luck. Didnt save any logs but will make one tomorrow. Any particular data i should log?

[SultanHassanMasTuning]

you have a log of changed that need to be made for SD and other parameters torque inverse not touched

log your fuel & torque sources

[askkmb]

2-3 pull.hpl Here you go. Let me know what you think. I still need to learn a lot from these coyotes and thats why im asking. Any help appreciated.

[rshoe09]

2-3 pull.hpl Here you go. Let me know what you think. I still need to learn a lot from these coyotes and thats why im asking. Any help appreciated.

woah
you really need to dial in your maf period table

[askkmb]

woah
you really need to dial in your maf period table

Whats the reason you say that? I know there are a lot of tables i need to calibrate and dial in. Thats why im asking for advice. There are 2 things i dont understand. Looking at the log you see that the stft are way off during light acceleration or deceleration even though my wideband shows the afr to be not too far off. Second the maf only gets to 86.69 lb/min. Is the maf maxed out?

[rshoe09]

is this a stick shift car or auto?
how much boost?
what injectors are in this as well?
something seems to be way off

[askkmb]

Read first post again. 7psi and id1000 injectors. It's an automatic.

[rshoe09]

Read first post again. 7psi and id1000 injectors. It's an automatic.

pm'd

[askkmb]

rshoe09 sent me some info over email(thanks) but id like to hear more input on this if anyone has some ideas.

[murfie]

Try raising the clyair WOT multiplier and seeing if the MAF limit you seem to be reaching goes away.

Im also confused why your using the pre ignition limit table to what seems like limit your spark. I'm not sure what effect this has on the other sources but I don't think it would be good. May want to rethink your approach to this and try a different method.

[ElecTech]

I've got a 2016 doing the same thing with, essentially the same kit. I think much of it is an airflow issue with the maf placement and tubing configuration. I originally thought that it was just the PID limit, even though I am using the DMR Air Flow channel, but fueling would no longer respond with table changes and the maf period would flat line at 96 micro seconds. In addition, the injector pw would flatline. This is right at 600 rwhp and letting off at 6000 rpm so we're getting ready to try a higher range MAF to see if I can get the range down to a more usable level. I thought I was crazy, but I have read others that have had inconsistent results with these.

[askkmb]

I have sent a few emails back and forth with rshoe09 and his approach was to actually lower the maf period table even though i actually needed more fuel up top. I thought it would go even leaner but it seems to be working.

Murfie - actually limiting the spark with the preignition limit table is something i got from the Ford HP tuners course from The Tuning School. I can't share much info as their material has copyright but i have used that before on n/a cars and have had no problem so far.

ElecTech - i was thinking the same thing when installing the kit. It goes from a 3" tube into a 4"(i think) maf housing and right after reduces again into smaller tubing. Not sure how much different a 2015+ kit would be but i think it might be the same in that aspect. If you look at the 05-10 kit you have the maf in front of the supercharger and i have never had a problem tuning those.

Another thing i noticed was that apparently when changing the maf period values it also changes the output from the map. I didn't know that these cars had a map but i get data in the map pid and it also responds to throttle changes.

[ElecTech]

I think they should have kept it a draw through and relocated the IAT. I'll see how the new MAF works and if we need to we can change the pipe to a consistent diameter to avoid issues.

The MAP is an inferred MAP that is calculated from airflow and things.

[15PSI]

First off, the PID value has a max of 86.69. It is not the maximum for the MAF. These MAFs will support a lot of RWHP. As previously stated, first raise your Cylair WOT Multi and Cylair Max Multi to 1.9. This gives the calibration some headroom. Next, raise the fuel enrichment rate to 1.9. Very important for blower motors.

Now you need to concentrate on the MAF transfer. Once you have the MAF close, then flash the new tune and re-log the car.

[ElecTech]

First off, the PID value has a max of 86.69. It is not the maximum for the MAF. These MAFs will support a lot of RWHP. As previously stated, first raise your Cylair WOT Multi and Cylair Max Multi to 1.9. This gives the calibration some headroom. Next, raise the fuel enrichment rate to 1.9. Very important for blower motors.

Now you need to concentrate on the MAF transfer. Once you have the MAF close, then flash the new tune and re-log the car.

I've tried all of that and normally I would agree, I fought it for awhile until I noticed the MAF period flatlining as well. It will not go below 96 micro sec. Eric also stated that the Airflow DMR should not be limited like the SAE PID is. Either I have a bad MAF or the airflow is stalling. Is what I'm thinking.

[wbt]

OP....send me a PM with your email and I will share a file for a Vortech v3 I just finished up this past week.

[askkmb]

Ok my biggest problem was my fuel trims were way off and needed to dial in the maf some more. Thanks for everyones help and advice.

Electech - do you already have results from a different maf and are you changing anything in the tubing? Not sure how much psi you are running or what your exact setup is but apperently the maf does not max out that easily as i thought. It only gets to about 60 lb/min now whereas it did to 86.69 before.

[ElecTech]

Ok my biggest problem was my fuel trims were way off and needed to dial in the maf some more. Thanks for everyones help and advice.

Electech - do you already have results from a different maf and are you changing anything in the tubing? Not sure how much psi you are running or what your exact setup is but apperently the maf does not max out that easily as i thought. It only gets to about 60 lb/min now whereas it did to 86.69 before.

We have one on order so I have yet to try it, but this car is currently at 9 psi at 6500 so it may see another pound by redline. We are going to try and keep the current MAF mount, but I had considered going to a more uniform tube configuration. I think the MAF will give me what I'm after. We had tried another stock MAF from a 2013 and it was reading very different in the low airflow areas also so I have my doubts about the condition of the stock sensor. Customer wanted to step the MAF up for future expansion anyway so we shall see.

Do you mind sharing your current MAF curve so I can compare? You can PM me if you don't care to post it.