Is Your Car Tuned Correctly?

[iggster]

here goes two logs of a tune for my car I tuned via mass air to perfect it. "take in mind that was the first time I EVER put a car on a dyno with me tuning it, I am not home so I dont have logs of any more recent with me"

one cruising one wot

Ill even throw in an idle video, thing idles like stock and no pinging no surging no hesitation, starts right up cold/hot ive tuned about 20 cars so far the same way and no one has made a single complaint.
https://www.youtube.com/watch?v=O56Ci4wSnW4

https://www.youtube.com/watch?v=-ngql3pe5ck

 

[iggster]

Im still trying to figure out what you mean by aftermarket cars?

galaxy auto correct FTL lol I meant aftermarket parts on cars

Lets take a for isnstance... 2013 gt500, with a 2.4 pulley, jlt maf, and a ford racing 65mm tb, would this be considered aftermarket? Should it be tuned with the correct mass air transfer curve or should the curve be adjusted by the tuner?

If the a/f is not what you "command" want then yes.... "got to look at STFT first before anything, and saying everything else is correct"

 

[blackshelby]

I took classes from greg banish he tunes for the OEMs and the way I tune through MAF is the way he tunes AFTERMARKET cars.

Classes where not cheap eather 1,500 each and its the only way you can unlock features on the pro racer program to tune ETC and transient tables and some other things.


Honestly this topic has allot of misinformation its gonna mislead allot of people.

I honestly don't think there is any misinformation posted here, actually some really good info here. Some I think is interrupted incorrectly.
I find it pretty hard to disagree what Ford is quoting and saying. We see the issue over and over on these forums with some of the tunes some members have put in their cars.
Greg Banish does give one of the better classes.
He is an OEM tuner for GM.
Greg will show you ways to get the curves close but will tell you that flowing is the most accurate way to do it and also is the way GM does it. He has told me that in the past.
He will also state how important it is to understand your complete fuel system flow if you do move you MAF transfer curve and understand what will happen if the curve is not correct.
If you don't you can and will be compensating for you fuel system in your MAF curve.
Again there are ways to do it fast and ways to get to to work but only one true way that is will be 100 percent accurate.

 

[itzl0l]

The main thing i was getting at:

If my base fuel table cammands lambda .81 (say at max load/boost)....and my wideband is reading a lambda of .81, but then I make a change to the intake (maybe jlt cold air).....I'm not going to turn around and make changes to the fuel part of my tune. Why would I? Thats not the variable that I changed. I'm going to make changes to the mass air model. The mass air model is correct when my recorded lambda matches my commanded (no other changes being made)

And this is exactly the way Banish teaches....I too have read his books and he has more background experience, both OEM and Aftermarket than everyone else in this thread combined.

....I see there as being 2 ways to do this...Obviously the OEM is going to use a flow bench (the only feasable way for them). But for us...when we start changing things around, I dont think adjusting the MAF xfer is wrong. Sure one has to be aware of ALL that it effects ...load/timing/transients. But to say it is wrong or not accurate is bull.

 

[blackshelby]

The main thing i was getting at:

If my base fuel table cammands lambda .81 (say at max load/boost)....and my wideband is reading a lambda of .81, but then I make a change to the intake (maybe jlt cold air).....I'm not going to turn around and make changes to the fuel part of my tune. Why would I? Thats not the variable that I changed. I'm going to make changes to the mass air model. The mass air model is correct when my recorded lambda matches my commanded (no other changes being made)

And this is exactly the way Banish teaches....I too have read his books and he has more background experience, both OEM and Aftermarket than everyone else in this thread combined.

....I see there as being 2 ways to do this...Obviously the OEM is going to use a flow bench (the only feasable way for them). But for us...when we start changing things around, I dont think adjusting the MAF xfer is wrong. Sure one has to be aware of ALL that it effects ...load/timing/transients. But to say it is wrong or not accurate is bull.

No you wouldn't move your fuel..
If you flowed the tube /meter and entered the MAF transfer functon obtained you would be dead on and have the full range of the sensor in your tune.

What do you do to your transfer curve where you cant reach yet ?
What happens when you change to a smaller blower pulley moving more air.... You would need to go back and do your method again and still can be off some again it might be close but not perfect. How do you verify your full range of the sensor is correct? You can't...... That method will be close again but never spot on for the full 0-5 volt range of that sensor.

"Obviously the OEM is going to use a flow bench (the only feasable way for them)"
No they do it because it is the correct way and the MOST ACCURATE WAY.

A question I have for you an any other aftermarket tuners. Why would you not acquire the transfer function for your tunes the most accurate way when its in your power to do so?

 

[itzl0l]

In that situation I personally would extrapolate the remainder of the curve. After all it is a 3rd order polynomial curve... and then datalog of course

The reason I prefer...and most likely alot of tuners...is that I can be there, with my laptop looking at the raw data. On the street or on the dyno and make real time changes.

I would be willing to bet that if I took a BA2600 in a JLT high boost....flowed it on a flow bench and then turned around and installed it on a car that I would still have to tweak it...it may not be alot...but once its in the car the maf xfer will still need adjustments to be 100%....obstructions around the filter (hood, fenders, fender liner ect, as well as any turbulance from ...well, driving....are going to apply changes to the airflow that a flowbench cannot simulate.

Its like tuning on the dyno vs the street with real world conditions.

OEM's do it with a flow bench because the platform is all the same...built in safety margines for variances of course. There is no way they could check/verify the MAF xfer of every car. Of course its accurate....but I dont think it is any more accurate or "right" than logging the car and making changes.

I mean....people take bone stock cars....adjust the tune and make power. If we all did things exactly the way the OEM intended we'd all be driving around a bunch of slow ass mustangs :beer:

 

[91svtbird]

I’m not at all surprised by the defense and endorsement of the all too common yet flawed and less than perfect aftermarket practice of routinely altering a known and accurate MAF when tuning. That’s why I stated in my article under the question “How to know if your tuner alters the MAF” I said this> “ I suggest you ask him. Most of the tuners that do it that way absolutely believe it is the correct way to tune because they have been taught that from the aftermarket software companies so they most likely will tell you if they do.”

You say “....I see there as being 2 ways to do this...Obviously the OEM is going to use a flow bench (the only feasable way for them). But for us...when we start changing things around, I dont think adjusting the MAF xfer is wrong. Sure one has to be aware of ALL that it effects ...load/timing/transients.”

Unfortunately this logic doesn’t hold true in today’s cars using a more advanced ETC which relies heavily on Load being 100% accurate that means the MAF has to be perfect. Maybe this isn’t as important in the 1% of the cars being used primarily for racing purposes but it certainly does matter for the 99% which are first and foremost street cars who’s customers expect to behave the same way it did from the factory. That means no hanging rpm’s , no surging, no part throttle detonation like we are seeing all too often especially in the newer 2011’s and up.

You also said this about taking a meter (in this case the JLT) and having it flowed on a bench “but once its in the car the maf xfer will still need adjustments to be 100%....obstructions around the filter (hood, fenders, fender liner ect, as well as any turbulance from ...well, driving....are going to apply changes to the airflow that a flowbench cannot simulate.”

I disagree. Ford flows all it’s meters on a flow bench then puts them in the car and they are not affected by turbulence from something as simple as “driving” which would rend the flow data less than perfect. Obviously if you installed a ram air hood or even a ram air duct to the meter you would have to be concerned about the adverse affects it might have on the meter but you wouldn’t be changing the meter curve you would just limit the amount of ram air influencing the meter possibly causing reversion. I would add also because of their inferior design some aftermarket meters lend themselves more so to those affects than say a proven design and highly tested Ford meter. A competent tuner should be able to spot that and warn their customer about using such a meter.

It’s unfortunate for the community that many tuners today still insist on using the old methods of tuning that alter an accurate MAF. That may have once worked and been acceptable on the less sophisticated PCM software of yesteryear but is clearly less than perfect in today’s more sophisticated and capable PCM ETC engine software. That practice can and has lead to many less than factory like poor driving characteristics and in some cases catastrophic engine damage in today’s more sophisticated cars.

We could go back and forth with this discussion but I will end it here. To each his own but buyer beware of who’s tuning your car and you need to weigh what are the risk’s involved once that tuner alters your PCM using those old less than perfect tuning methods. Today’s engines cost upwards of $26K




PS “I mean....people take bone stock cars....adjust the tune and make power. If we all did things exactly the way the OEM intended we'd all be driving around a bunch of slow ass mustangs ”


LOL….Tell that to the tuner of the fastest Cobra Jet in the country @ Tasca Ford who tunes using a properly flowed MAF .

 

[charba951]

This is all way above my pay grade

 

[SRT8tech]

So, if you are using the stock MAF, injectors and Throttle body you should be ok? Sorry for the stupid question.......

 

[Eric@HPTuners]

This thread is really misleading. My $.02

 

[onlya302]

I agree with Eric...

While it is definitely possible to calibrate using the OP's method, however it would make most calibrations cost in excess of $1500, I don't know of too many customers that are willing to pay that for a calibration using an OEM PCM...

 

[Eric@HPTuners]

I agree with Eric...

While it is definitely possible to calibrate using the OP's method, however it would make most calibrations cost in excess of $1500, I don't know of too many customers that are willing to pay that for a calibration using an OEM PCM...

This thread makes issue of something that is not an issue. I will agree there are a ton of tuners that haven't the slightly clue what they are doing, and make it by using value files and the like without understanding any of it. This isn't about this....

It would be a dream to have the type of data that Ford has when they calibrate a car. The entire intake assembly (airbox to throttle body) is flowed to get the MAF transfer function.

If something is changed after the fact, the transfer function is no longer correct. That is why we adjust the transfer function in the first place. It is not incorrect to adjust the MAF, as this thread would lead someone to believe.

My question to the OP.... are you a tuner?

 

[Brutal Metal]

My question to the OP.... are you a tuner?

:lol1:

 

[forddood]

I think this thread was started by someone who sole intention was to stir up shit.

 

[truckguy]

There are some good points in the article and some that are missed....Unfortunately the article seems to be a scare tactic to make people freak out about their tunes.

In an ideal world you would have everything flowed on a bench, input the data, and the car would run. If you have the tools and means to do so, then by all means do it. That is probably the most accurate and best approach. However, if you dont have the means to do it, then sound mathematical principles do apply.

Basic math tells you that if you know 2 parts to a 3 part equation, then you can back calculate the 3rd part. If you dont believe that, then you probably shouldnt be standing under any buildings using modern architecture.....The principle behind tuning the maf transfer function is simply that you know how much fuel the injectors are flowing (ford racing actually supplys that data and a good tuner always uses injectors with known data) and you know what air fuel ratio the pcm is requesting so some simple math tells you how much air is coming across the meter. Its that simple but in order for that to work properly, you need to have 100% accurate injector data and your testing equipment needs to be good quality and mounted in the proper locations(example, lab grade wideband in the collector not a budget wideband used as a sniffer...), and there cannot be any leaks behind the wideband. If it is done that way then calculated load will not be off and your spark advance will be correct. The key is that you have to start with good known data.

The big problem comes in that alot of tooners use junk equipment and arent educated on how to do things properly. Alot of them simply believe that any fueling error comes directly from the maf which simply is not the case and in those cases simply tweaking the maf is absolutely incorrect. Just as incorrect as saying you cant tune a car without having your intake flowed on a flow bench.

 

[truckguy]

The other thing to think about with a flow bench (unless you are flowing every single meter you are doing) is what is the margin of error on the maf's themselves? Does every single intake tube flow identical? Ect....I would almost guarantee that not every sensor reads 100% identical nor does every intake tube flow exactly the same due to production variances, so if you are using flowed data from 1 sensor and 1 housing and then applying it to every other sensor and housing out there of the same combination, your load calculations are going to be off by whatever % the sensor is off plus whatever variance the housing has in it as well.....Just food for thought

 

[Brutal Metal]

I think this thread was started by someone who sole intention was to stir up shit.

And create Fear:nonono:

 

[dcarlson]

There are some good points in the article and some that are missed....Unfortunately the article seems to be a scare tactic to make people freak out about their tunes.
<...>

Basic math tells you that if you know 2 parts to a 3 part equation, then you can back calculate the 3rd part. If you dont believe that, then you probably shouldnt be standing under any buildings using modern architecture.....The principle behind tuning the maf transfer function is simply that you know how much fuel the injectors are flowing (ford racing actually supplys that data and a good tuner always uses injectors with known data) and you know what air fuel ratio the pcm is requesting so some simple math tells you how much air is coming across the meter. Its that simple but in order for that to work properly, you need to have 100% accurate injector data and your testing equipment needs to be good quality and mounted in the proper locations(example, lab grade wideband in the collector not a budget wideband used as a sniffer...), and there cannot be any leaks behind the wideband. If it is done that way then calculated load will not be off and your spark advance will be correct. The key is that you have to start with good known data.

The big problem comes in that alot of tooners use junk equipment and arent educated on how to do things properly. Alot of them simply believe that any fueling error comes directly from the maf which simply is not the case and in those cases simply tweaking the maf is absolutely incorrect. Just as incorrect as saying you cant tune a car without having your intake flowed on a flow bench.

Everything he said^^^^

Plus:
In many situations the factory MAF Transfer data is no longer accurate in the "as installed" condition because of changes to the DISTRIBUTION of airflow through the meter itself brought about by the instalation of non-factory parts immediately in front of or behind the meter. THe MAF sensor DOES NOT measure ALL of the air that goes thought the entire MAF sensor housing. It only measures the air that flows over the small electronic element. Placing a bend in the intake tubing in front of the MAF, for example, will disupt the laminar flow over the MAF sensor element and produce uneven distribution of the air going through the MAF housing. Once this happens all of the factory MAF calibration data is inaccurate.

 

[1998ws6]

When you have a pullied 2003 cobra with a JLT intake and a stock maf, what variable do you adjust when the fueling is incorrect as measured with your lab grade (AFM1000/Horibra/ETAS) wideband?

The general concept of having the MAF correct, is valid, and why calibrated meters have no place in a modern vehicle I will agree with. I am curious to see the answer to the question above. Or do you just let the car out the door with a lean airfuel ratio because the MAF xfer function is still stock so the tune must be perfect?

 

[Shaun@AED]

I'm going to have to agree and disagree at the same time. LOL (Some good info, and some very misleading as well)

The Airflow Model of the calibration should be modified appropriately for changes that affect the VE of an engine. This has nothing to do with the Maff.

Maff = Reactive fueling
Airflow Model = Proactive fueling

Get the Airflow Model correct and the Maff is cake. Real flow data can be used assuming the intake 'system' has been designed correctly. (Read dcarlson's post above)