Thank you for sharing. Do they make a tank that sits flush in the tire well?
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Self Tuning With SCT Pro Racer
- Thread starter 03cobra#2
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I'll continue to update here. I have been tweaking the tune that my tuner gave me. Just adjusting idle really. I have a nice steady idle at 875. Key was getting the spark down to 10-13.
Still having a issue with rich tip in. When I press the pedal it goes rich for a split second then goes right to commanded af. I finished the failed maf table best I could. Made no difference on the rich tip in. Also disabled anticipation logic (Acdc switch)... Made no difference.
I am hesitant to change manifold volume as I have read it can affect other things in the tune.
I am going to go off into the weeds and play with the transient fuel settings.
Any suggestions on my rich tip in would be welcome.
Still having a issue with rich tip in. When I press the pedal it goes rich for a split second then goes right to commanded af. I finished the failed maf table best I could. Made no difference on the rich tip in. Also disabled anticipation logic (Acdc switch)... Made no difference.
I am hesitant to change manifold volume as I have read it can affect other things in the tune.
I am going to go off into the weeds and play with the transient fuel settings.
Any suggestions on my rich tip in would be welcome.
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What fuel was it tuned on?
Wanting to check my failed maf table I started the car unplugged the maf and it died. Uploaded the stock failed maf table and tried it again. Car stays running. Guess my failed maf table needs some work.
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How rich is it going? I can't remember how it acted on the stock stuff with mine. I have the MS3 set to go a little rich depending how far I press the accelerator.
At this point I'd get the data and run the LWFM table histogram. I want to say that'll affect tip in, but I don't remember.
At this point I'd get the data and run the LWFM table histogram. I want to say that'll affect tip in, but I don't remember.
It goes to like .7x lambda or so for like a split second. I need to figure out this failed maf table.
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Just follow that video I posted. I think I got about 45 minutes worth of data to populate mine and the histogram made it really simple.
I think where I'm having the trouble is finding TP reletive in livelink.
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If you gave him some dimensions I bet he could. I know they DO make those in general but I don't know who. Like I said I bet that guy could do it tho, pump in tank and everything etc.
I have been doing some research on my rich tip in / lean tip out. When I datalog during cruising the wideband goes down to about .75 lambda for a split second when I press the pedal..... then goes to the commanded AF. The results are repeatable every time....regardless of what I have set up for my failed maf table, and if I have anticipated fueling logic enabled or disabled.
I have a very basic understanding of how Ford (and other manufactures) deal with transitional fueling...they use a theory called X-Tau (it's basically a model / theory that there is literally a puddle of fuel that sits on the intake valve and intake walls. So each squirt of the injector not all the fuel makes it in the cylinder during fuel transition so there is compensation for this). My basic 5yr old brain understanding is that during the throttle transition the ECU will compensate (for a very brief moment) to make sure AF is steady while fueling is transitioning. Some people adjust the manifold volume to try and fix this which is pretty much a scaler that can / may fix the problem but it does affect other areas of the tune.
In the SCT PRP software there is a section for transitional fueling. I believe this is the area that I need to adjust. It takes a lot of time and trial and error so most tuners will not deal with this and say "if it's not that bad just leave well enough alone". There are 3 parameters to adjust. From my understanding the parameters adjust what the ECU thinks the size of the "fuel puddle" in the intake, how long this fuel puddle takes to evaporate, and the 3rd is a multiplier for the 2 settings. If the fuel puddle is bigger or smaller then what the ECU thinks then you will have lean / rich tip in when you step on the gas pedal.
Next step is I'm going to start playing with these parameters and see how it affects things and head down that path. I'll gladly share my results as there is not a lot of info on this subject.
I have a very basic understanding of how Ford (and other manufactures) deal with transitional fueling...they use a theory called X-Tau (it's basically a model / theory that there is literally a puddle of fuel that sits on the intake valve and intake walls. So each squirt of the injector not all the fuel makes it in the cylinder during fuel transition so there is compensation for this). My basic 5yr old brain understanding is that during the throttle transition the ECU will compensate (for a very brief moment) to make sure AF is steady while fueling is transitioning. Some people adjust the manifold volume to try and fix this which is pretty much a scaler that can / may fix the problem but it does affect other areas of the tune.
In the SCT PRP software there is a section for transitional fueling. I believe this is the area that I need to adjust. It takes a lot of time and trial and error so most tuners will not deal with this and say "if it's not that bad just leave well enough alone". There are 3 parameters to adjust. From my understanding the parameters adjust what the ECU thinks the size of the "fuel puddle" in the intake, how long this fuel puddle takes to evaporate, and the 3rd is a multiplier for the 2 settings. If the fuel puddle is bigger or smaller then what the ECU thinks then you will have lean / rich tip in when you step on the gas pedal.
Next step is I'm going to start playing with these parameters and see how it affects things and head down that path. I'll gladly share my results as there is not a lot of info on this subject.
that's good interesting data and I am still curious on your results but I am leaning more towards megasquirt / holley for my future tuning goals that way I don't need to learn all these Ford secrets.
great work
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great work
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I think the stand alone systems have settings / adjustments for transitional fueling as well. They may be a bit easier to understand.
They do. The Megasquirt has multiple ways of dealing with the transitional fueling. Including dealing with the fuel puddle. I've read up on a couple guys that have gone that route. They said the driveability is awesome going that way, but it's way over my head right now.
I never messed with the fueling transitions. Hopefully it works out for you.
Edit:
Got a little time to play with transitional fueling....no luck so far. I adjusted the table lower for puddle size but didn't seem to have any affect. I will make big changes to the other tables and see if I can get any results either way.
If that don't work I will put the tables back to stock and work on the failed maf table. From my limited understanding of that table the ECU will take data from that table during fuel transition. From what I have read if I decrease the load values it may take away fuel during transition.
Just thinking out loud but at lease I have some stuff to try.
If the failed maf table is dialed in would you be able to drive the car with the maf unplugged? When I start the car and unplug the maf the car does continue to run so at least the table is in the ballpark.
Got a little time to play with transitional fueling....no luck so far. I adjusted the table lower for puddle size but didn't seem to have any affect. I will make big changes to the other tables and see if I can get any results either way.
If that don't work I will put the tables back to stock and work on the failed maf table. From my limited understanding of that table the ECU will take data from that table during fuel transition. From what I have read if I decrease the load values it may take away fuel during transition.
Just thinking out loud but at lease I have some stuff to try.
If the failed maf table is dialed in would you be able to drive the car with the maf unplugged? When I start the car and unplug the maf the car does continue to run so at least the table is in the ballpark.
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doesn't The lasota book not go into detail on this? if I did get SCT I would be buying the book. too.
check this link out seems to cover exactly what you are experiencing
https://www.svtperformance.com/thre...what-is-it-really-tuning-bits-inside.1039630/
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check this link out seems to cover exactly what you are experiencing
https://www.svtperformance.com/thre...what-is-it-really-tuning-bits-inside.1039630/
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Update:
I was having trouble getting my frps to log in LiveLink...I did a A/B comparison of a old tune that had it working to my current tune, and went through like 100 parameters and finally found the one that was turned off. Took about an hour of trial an error but finally got it lol....so now my frps logs like it should.
Back to my tip in issues. I did a tune that has the transitional fuel tables reduced like 50% and a tune that had most of the failed MAF table reduced by about 20%....loaded them on my programmer and headed out for a drive.
Changing the transitional tables didn't seem to have any effect....the rich tip in and jerk was still there. I loaded up the tune with the failed MAF table adjustment and I think I may be on to something! I was only able to do a bit of driving before work today but the car didn't really seem to jerk / buck in first gear and behaved very well in the short amount of driving I did. So it looks like the ECU pulls data from the failed maf table during throttle transitions. I'll do a bit more driving but I'm hopeful that I am close to nailing this thing (fingers crossed)
Also I have a under hood ice tank on the way, and I'll be getting it on the dyno next week for some updated numbers. This time I'll be using the Mustang dyno at my work (finally cleared off and ready to go) with my onboard wideband. The goal here is to make sure the AF is good at WOT with cooler intake temps and tweak the final timing if needed (tuner said he could only get a max of about 18* even though the tune is set for about 22*). I have no idea how my mustang dyno here at work will read in comparison to the mustang dyno I got the readings from last week at the shop I took it to.
All in all, I would put the tune at about 90% done and I can really enjoy the car now. I love tinkering / tweaking in general and it's really fun now that the car is just about done. I'll post back with updated numbers once I get things finalized.
I was having trouble getting my frps to log in LiveLink...I did a A/B comparison of a old tune that had it working to my current tune, and went through like 100 parameters and finally found the one that was turned off. Took about an hour of trial an error but finally got it lol....so now my frps logs like it should.
Back to my tip in issues. I did a tune that has the transitional fuel tables reduced like 50% and a tune that had most of the failed MAF table reduced by about 20%....loaded them on my programmer and headed out for a drive.
Changing the transitional tables didn't seem to have any effect....the rich tip in and jerk was still there. I loaded up the tune with the failed MAF table adjustment and I think I may be on to something! I was only able to do a bit of driving before work today but the car didn't really seem to jerk / buck in first gear and behaved very well in the short amount of driving I did. So it looks like the ECU pulls data from the failed maf table during throttle transitions. I'll do a bit more driving but I'm hopeful that I am close to nailing this thing (fingers crossed)
Also I have a under hood ice tank on the way, and I'll be getting it on the dyno next week for some updated numbers. This time I'll be using the Mustang dyno at my work (finally cleared off and ready to go) with my onboard wideband. The goal here is to make sure the AF is good at WOT with cooler intake temps and tweak the final timing if needed (tuner said he could only get a max of about 18* even though the tune is set for about 22*). I have no idea how my mustang dyno here at work will read in comparison to the mustang dyno I got the readings from last week at the shop I took it to.
All in all, I would put the tune at about 90% done and I can really enjoy the car now. I love tinkering / tweaking in general and it's really fun now that the car is just about done. I'll post back with updated numbers once I get things finalized.
His book does go into detail on how to configure. When I filled in the table according to my datalogs and pulled the maf while the car was running it died immediately. So I loaded the stock failed maf table and pulled the maf while the car was running and stayed running. So my process to dial in the failed maf obviously was wrong and the stock table is at least in the ballpark. So hopefully getting this dialed in correctly is the key to smoothing out the part throttle driving.
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Been working on my failed maf table. I used the histogram feature in livelink and filled in a bunch of cells. I started the car and pulled the maf and the car continues to run. It is extremely rich though. At idle my wideband reads around .75 lambda. I can Rev it and it's really rich. So I'll Continue to dial in the failed maf table and see if I can get the car to run decent enough with the maf unplugged. Hopefully with a good dialed in failed maf Table it helps with transient fueling.
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Are you using the ability to move tables out of PRP into Excel? It's really handy. You can pull two versions of a table out of PRP, compare them or manipulate them in Excel, and copy a revised version back to PRP. It's really handy.
What I'm thinking is maybe compare the table you just made with the stock table, but reverse the changes. If the stock table value is 1.0 and your new table is 1.2, then try running 0.8 instead. It could be you made the right changes but in the wrong direction. BTDT.
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