Need help tuning Idle, MAF X-fer etc

Devman

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Hello
I have an 01 cobra with an eaton swap and I feel my tuner doesn't really take the time to get the car right he just tries to make as much power out of it safely. I have a Steigmeir Stage 8 port with dragon port matched plenum and dragon throttle body with Venom cooler and a 10 pound lower and I think a 3 inch upper id have to go measure the upper to make sure. I also have the JLT 12" high boost CAI and that's where I think my problem might be coming into play. The main problem I'm having is my idle. Ive heard that a lot of people with these dragon throttle bodys have a surging idle. Before I had a JLT high boost CAI I had a BBK CAI with a SCT BA 2600 MAF. And since ive installed the JLT high boost CAI I put the SCT BA2600 sensor into the JLT tube itself, no more need for a MAF housing as the JLT tube has a slot directly in it for the sensor itself and ever since then I have had an idle issue it bounces back and fourth between 1000 and 1400. Also since installing the JLT CAI ive had a po171, p0174, p0420, p0430 and a p1506. I have access to both the advantage 3 software and the sniper software I got them just recently which i still have to go to dyno classes so any help with correcting my idle issue would be greatly appreciated I do believe setting up a good MAF transfer function might help or anything that has to do with the amount of air flow coming through the intake or maybe iac duty cycle or something. I am aware that ford calculates their MAF transfer functions with a flow bench but I don't have access to one so I figure their has to be some kind of equation to calculate maf transfer function maybe based off spark, load, torque or something. If you need access to any of my tune or datalog info let me know. Also another problem I am having is when my car is on the dyno and it gets to 18 pounds of boost around 3500 to 4000 rpms it drops to 14 and stays there and I don't think this is belt slip so if anybody has any ideas on that it would be greatly apprected as well. Sorry for writing a lot and writing more then one subject in one thread.
 

cj428mach

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Is your motor built? Thats a lot of boost for a stock 01 cobra motor.

You "determine" your maf tranfer based off a wideband reading, make sure you have a wideband.

I suggest installing a screen in front of your MAF, it'll more than likely require you cutting the tube right before the MAF.
 

Devman

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Its a well built short block, the only think still stock is the cylinder heads and they have been rebuilt and ported, 32cfm over stock.

And yes I do have a wideband 02 sensor as well.

Why should I install a screen in front of the MAF
 

Pro60modman

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Tuning the Mustang is pretty easy. Setting it up for tuning can be difficult. You can tune the MAF transfer two ways. First you setup the Live Link logging software. Monitor RPM, TPS, Open Loop Flag, MAF counts, Spark final, Coolant Temp, ORANGE WIRE INPUT(rename it AFR), STFT and LTFT. Second you lock your car in open loop, lock timing at 10 or 15 degrees and change your entire base fuel table to 1.00 lambda up to the load point you see 2psi. Then you need to log the wideband into your SCT handheld using the 5v output of your wideband gauge linked to the orange input wire of an SCT 9608 analog cable(it fits the X4, trust me). Then you warm the bitch up fully and let it idle for 2 minutes while logging it. Since your already somewhat tuned you can skip to step 67 where you put it in 3rd and let it roll at idle speed. Start the log and progressively give it gas(try to hit each MAF count cell over 500 times) until you get to a lambda point that on the base fuel table that isn't 1. This not only tunes your closed loop fueling for the most part but also gets the switch area of the MAF from closed to open loop pretty well tuned so you don't have initial WOT AFR squiggleyness.

The 2nd way is less complicated but only works if your fueling is pretty close from the get go aka your car doesn't run like garbage. You disable LTFT and run STFT only. While some say you don't have to, just do it. Fords log LTFT inverse of any other car and you'll catch yourself messing up calculations when adjusting the MAF counts. SOOOO, you log STFT only and make adjustments. Lock your timing to 10 or 15 and set the base fuel table to 1 across the board(dont forget to save the original table). Log idle and a 3rd gear pull from idle to 2psi with EXTREMELY GRADUAL THROTTLE so you can get 500+ counts per cell on your LiveLink histogram. Make your adjustments to the MAF transfer function based on the percent of fuel added or subtracted by the STFT at each MAF count point.

After you have your fueling all setup you also need to setup your Failed MAF and predicted fueling stuff since your 99+. Along with tuning in the maps related to the ISC integrator to get that idle perfect and checking the dashpot decay times in relation. Then you can get to the fun stuff like ignition timing or setting ridiculous idle ignition parameters to make it chop like an old Vince Shlomi infommercial.

Now. All this said, there are tens of maps that need to be changed in order to lock the car in closed loop, lock timing, etc. Other things that need to be monitored on the log, histograms need to be setup and it's always a good thing to know how to check the history function of the SCT AdvIII software so you don't forgot to turn something back on.

I understand that this is a lot of ****ing shit to do and I just generalized it. Any tuner can tune for power on a Mustang that's the easy part. The hardest ****ing part of tuning these things is the low end and idle stuff in my experience. If you are going to try and tune it yourself PM me with any questions, if you say **** that and want someone else to tune it you can PM me about that too.
 
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decipha

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its best to fix the problem, all modified inlet pipe setups should have screens on them

however, in some circumstances where thats just not probable you can fail the maf at idle and run a predicted airmass, the backflow clip function is there for that, not ideal but in a pinch
 

Devman

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Hey guys thanx fort all your input sofar it is greatly appreciated especially you Pro60modman. I have access to both the advantage 3 software and the sniper commando software which I kinda like better. Sofar wat I have done is calculate the difference in area between my old sct maf housing I.D.(3.5) and the area in the jlt high boost I.D. right by the maf sensor which is 4.25 and I think I came up with 1.395, i forget exactly but I have it on my computer and I multiplied that to all the air flow values in the maf transfer function and now it idles just right it's not bouncing around or hunting anymore and it's dropping pretty nicely between gears, however it's staying up around 1100 and when the car is rolling and in neuch it stays at like 1500 to 1600 and I'm wondering if I shuld adjust iac duty cycle for neutral and drive for that. Also when I get to about 3200 to 3500 it starts to run way rich because like you said most tuners can make power easy but when it comes to drivability, low end and idle they don't care cuz they just wanna get u out the door and take ur 500 to a 1000 dollars and have u come bak and do it again.
 

Devman

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So now tht I've adjusted my maf transfer I gotta go bak and adjust fuel spark air/fuel etc but I wanna get my idle dialed in more and then I'll go do all that granted that's the right way to be doing it. If you guys think different let me know. I am a Ford technician and I can turn wrenches like crazy and do just about watever and same thing goes for the Ford IDS software but this tuning gig is new to me but I'll figure it all out plus I got the LaSota tuning manual for sniper and that had been helping alot too
 

Pro60modman

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The Lasota manuals are very helpful. He goes into the step-by-step to set the car up for open or closed loop MAF tuning. I had a customer give me all his tuning gear after he gave up trying to tune his car and I read through his SCT manual. I could have spent $75 years ago and not gone through the days of BS figuring out SCT. The decipha guy who posted above also wrote some killer write ups that helped me a lot. Knowing what to adjust and what order is one thing but LaSota and Decipha's manuals fully explain the why. Fully understanding the Why saves you time solving problems and saves a LOT of frustration.

Get your MAF transfer function perfect before getting into the other stuff. If you have the manual I would recommend using the open loop method, tuning the curve with the timing locked, get it really perfect, then go to method 2 using STFT and unlock the timing, put the base fuel table back the way it was, and turn on your closed loop. Log it all over again and readjust your MAF transfer. Make sure you have your open/closed loop switch parameters in your head and pay attention to your logs so you don't mistakenly adjust MAF to far up the function when STFT tuning.

Glad your getting it all worked out! Tuning your own vehicle is always something to be proud of. Tuning is my absolute favorite thing to do.
 

Devman

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With regards to my idle staying at 1100 while not moving and staying between 15 and 1800 while rolling what should I do should I adjust ISC duty cycle 4 neutral and drive or is there something else I can do because my idle is set at like 850 but it doesn't want to come down to that. It's idling good it's not bouncing around or hunting and is dropping nicely between gears now I'm just trying to figure out how to get it to where it's supposed to be. I can't adjust the throttle screw anymore and I haven't tried tinkering with the throttle position sensor yet although I know that's where it's supposed to be. If you have any ideas on what parameters I can change to make my idle where it should be let me know
 

Pro60modman

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Reset your KAM by unplugging the Neg battery cable and turning on the high beams for a minute and put it all back together.

Start the car, and drive it around until its fully warmed up
Unplug your TPS and ISC
Adjust the throttle blade screw to the point the car will barely idle
Turn the car off
Plug everything back in
Turn the key to the ON pos.
Calibrate the TPS to .96-.98
Check your idle and get back to us
 

Devman

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Well I was in the process of doing that so I go and reset my KAM with my Livewire TS and go to let it warm up cause I don't move my cars until the warm up but especially my mustang, it doesn't like to move when its cold but anyways I reset my kam and once it was warmed up it was idling just right it seems like, I'm lookin back at my datalog now and it looks like between 880 and 950. My idle is set at 850 for neuch and drive. I haven't drivin it yet cause it just snowed but while coasting she hangs around 1500 to 1800.
 

98turboedgt

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Guys I need help tuning my 98 turboed gt. I’m struggling with the Livelink. Right now it’s got a base tune from lasoto but using his book to dial in the maf transfer I’m hung at the begginig logging maf ad counts and I have no clue what I’m doing.
 

01yellercobra

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Guys I need help tuning my 98 turboed gt. I’m struggling with the Livelink. Right now it’s got a base tune from lasoto but using his book to dial in the maf transfer I’m hung at the begginig logging maf ad counts and I have no clue what I’m doing.

Start a new thread. Let us know exactly what problems you're having.
 

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