C&L and A/F ratio - tuning

[twogts4us]

C&L MAF and A/F ratio - tuning

I am really confused and frustrated. Back in December I had Flowmaster Amer Thdr catback, FRPP 3.73, Pro 5.0 shifter and Superchip SCT installed by a local Mustang Only speed shop. I feel like I paid way too much for the chip and dyno tune ($627.00 total for the chip, install, & dyno time/tune) and the results, to me, were not that impressive. See dyno sheet below. What concerns me most is what I am hearing, learning, and about what it should be - the A/F ratio.
In February I installed a C&L MAF and Trueflow tube as well as an Accufab 70mm TB and plenum. The car has run perfectly since the install, is very responsive and does not ping at all. But I am learning that the C&L simply leans the A/F out more to make power. I am really worried sick now that the car is running way too lean. I have had absolutely no problems with it. I did leave a msg for my tuner, but he has yet to return my call - nice! Any advice? I am tempted to yank the C&L out and put my OEM MAF back in. My sincere appologies to anyone I have offended out there, because I was I defender of the power the C&L MAF made...sure, it makes power...but I don't want to burn a piston or something. Any advice is appreciated.

 

[Go HoTO!]

This is a great post and I am in the same boat as you. I also want you to know, that I am not an expert, but I will tell you where I am at with this issue:

1 - Correct, the C&L MAF "works" by leaning you out. This is how it adds power.

2 - A/F meters is not an exact science. What really matters is what is happening in the head. Accuracy of this testing is questionable.

3 - Have you ever heard of someone wrecking a motor with these mods on an NA car with stock compresson? Me neither. And I have asked EVERYWHERE.

Result, don't worry too much about this. Serious motor heads with serious add-ons go nuts with these, but for standard bolt-ons, I think we are all ok and it is even probably a good mod. If you are worried about leaning, pull your plugs and read them. If they are grey or white, you have a lean condition problem. If they are brown, this is borderline, but livable. Darker than that, and you are SAFE. This si the ONLY way to know for sure.

I have not pulled mine yet, but I am going to. Let me know if you do and what you find.

BTW, was the dyno before or after the C&L mods?

 

[Go HoTO!]

On a slightly different note, our cars run very well tuned when stock. The computers are pretty good. As you have found out, running a custom tune with your mods just does not pay. Custom tunes should be reserved for things like new cams and when blowers are added.

The bright side is that now you have the chip and you can tune it whenever you want.

 

[billyfe390]

You do not need an after market maf unless you are pegging the stock one out voltage wise.
Sorry to say but you simply wasted your money getting that MAF put the stock one back on and find a different tuner your A/F should not cascade like that it should pretty much stay 12.8-13.1 from 2200 to 6000.

 

[Go HoTO!]

Only one problem, the C&L MAF Kit utilizes the stock MAF. It just has a larger sample tube and is a larger diameter. Think of it as an improved design over stock rather than a different MAF. The result is more hp through a leaner A/F. Hence the contraversy.

The other option is a diferent MAF altogether that is calibrated for different fuel injectors.

 

[mogs01gt]

twogts4us
As said on modulardepot, you are running too lean. You may want to take off that C&L or get a retune even though the tune will cost you. From looking at your dyno, your tune may also be causing a problem.

here is my dyno.

 

[billyfe390]

Only one problem, the C&L MAF Kit utilizes the stock MAF. It just has a larger sample tube and is a larger diameter. Think of it as an improved design over stock rather than a different MAF. The result is more hp through a leaner A/F. Hence the contraversy.

The other option is a diferent MAF altogether that is calibrated for different fuel injectors.

It is not improved it is just fooling the stock electronics which brings the A/F down as well as the voltage. It still doesnt do anything but mess up his existing tune and cost money.

Unless you forced inducted or are over 300 RWHP you do not need an aftermarket MAF. Defend the C&L all you want but you are missing the point. With his mods he is no where near pegging the voltage of his stock maf and on top of that he already had the A/F leaned out(which needs to be looked at by a different tuner) so tell me what it does again.

 

[99 silvr35th]

I'm also having the same problem with the C&L except I also get a check engine light which says I'm running lean (per auto zone). Speaking to others the say that I am not harming the car by running it with the C&L, does anyone agree or disagree?
I get noticably increased hp from the C&L as well as a stiffer gas pedal, overall the car fells quicker with it, BUT if i'm actually doing more bad than good let me know so I can pull it off....thanks.

 

[twogts4us]

This is a great post and I am in the same boat as you. I also want you to know, that I am not an expert, but I will tell you where I am at with this issue:

1 - Correct, the C&L MAF "works" by leaning you out. This is how it adds power.

2 - A/F meters is not an exact science. What really matters is what is happening in the head. Accuracy of this testing is questionable.

3 - Have you ever heard of someone wrecking a motor with these mods on an NA car with stock compresson? Me neither. And I have asked EVERYWHERE.

Result, don't worry too much about this. Serious motor heads with serious add-ons go nuts with these, but for standard bolt-ons, I think we are all ok and it is even probably a good mod. If you are worried about leaning, pull your plugs and read them. If they are grey or white, you have a lean condition problem. If they are brown, this is borderline, but livable. Darker than that, and you are SAFE. This si the ONLY way to know for sure.

I have not pulled mine yet, but I am going to. Let me know if you do and what you find.

BTW, was the dyno before or after the C&L mods?

That's probably a good idea, pulling the plugs to check their condition. Since it is such a chore on this motor, it'll give me a good excuse to install Denso Iridium plugs!
Yeah, please share what you find and I'll do the same...
Thanks!!!

 

[twogts4us]

twogts4us
As said on modulardepot, you are running too lean. You may want to take off that C&L or get a retune even though the tune will cost you. From looking at your dyno, your tune may also be causing a problem.

here is my dyno.

Yeah, I know, I'm a Mustang forum whore . I don't mean to whore around, looking for the answer I want to hear, but rather gathering as much info, experience and support from fellow bolt on gear heads who have had similiar issues. I do see you have a C&L MAF, but a much richer and flat A/F ratio . As you stated, my tune, which was before adding the C&L MAF, was a possible problem to begin with, which I am aggravating with the C&L MAF. Still no call back from my tuner since Monday...I think I'll try calling him again right now. Thanks for the advice.

 

[twogts4us]

BTW, was the dyno before or after the C&L mods?

Dyno was done with the newly installed Flowmaster American Thunder Cat-back and new 3.73s installed. Since then, my wife and I, in February, bolted on the C&L 85mm MAF kit with Trueflow Tube and Accufab 70mm TB and plenum.