[heeke]

I just put new Ford Racing Y302 heads on my Mustang, and added 30lb/hr injectors. Spent most of the day trying to get it to idle with the DA1 speed density. I think I am ready to convert to Mass Air and buy a Quarterhorse.

I started looking for components for the conversion, I am looking for opinions about mass air meters, C&L, Pro-M, Ford... I see several advertised for xxlb/hr injectors, I am a little confused by this, the meter measures air flow, are they "cheating" by telling the car an incorrect air flow to offset bigger injectors? If so I think I should get a "19lb/hr" meter that reports the correct amount of air, right?

Does it matter if I get a MAF sensor for the 88-95 (oval) or the late square style as long as I get the correct pigtail?

Thanks in advance for your help
Greg

[decipha]

the gufx ecu is a direct swap simply unplug the old and plug in the new

need to run 4 wires for the maf but its pretty straight forward

I'd recommend a lightning 90mm maf can be had for $100 all day long, works very well is proven its is stock ford, its also not restrictive being 90mm

[AdderMk2]

I run a 90mm LMAF and I'm glad I finally just did it.

Avoid any MAF that uses the words "Calibrated for XYZ injectors" Often times they will not report correctly, and they make tuning tougher.

[EDS50]

I run a 90mm LMAF and I'm glad I finally just did it.

Avoid any MAF that uses the words "Calibrated for XYZ injectors" Often times they will not report correctly, and they make tuning tougher.

All mass air meters/sensors are calibrated though the ecu to work with a certain injector. The aftermarket MAF meters are calibrated to a certain injector by modifying the electronics of the sensor or using a sample tube to trick the ecu. With a tuner tool like the QH, virtually any MAF can be tuned or calibrated properly to work with any injector without tricking the ecu, some combinations are easier than others.

[decipha]

Ed. there is no such thing as a calibrated MAF from the factory, the 90mm lmaf is not calibrated for 42# injectors, its setup in the lightning ecu with the maf transfer and the 42# injectors, there is no "compensation" work being done by the ecu hence its not 'calibrated'

what Keith is saying is that 'calibrated' maf sensors usually do not read linear so when trying to dial them in the curve looks as though it was made by a toddler

[EDS50]

It seems to me there is a misconception as to what calibration means and how the definition of the word is being used by different people. That was my point. I will edit my post to be more clear.

[EDS50]

Mike, is it safe to assume that the ecu will always be performing some sort of compensation regardless what maf is used when adaptive learning is enabled?

[cgrey8]

Calibration refers to a MAF that has a curve specifically engineered for a specific application (e.g. 89-93 Mustang) to replace the stock MAF when upgrading injectors in that same application. The calibration has just as much to do with that application's stock tune (specifically the tune's MAF curve and injector parameters) as it does the injectors it is calibrated for. For instance, when you upgrade to 30lb injectors on a 93 Mustang GT, you can get a MAF cal'd for that application to ATTEMPT to let you run 30lb injectors on that setup without a tune. However it'll be a slightly different calibration if you are upgrading to those same 30lb injectors on a 93 Mustang Cobra because the original EEC's MAF curve and original injector parameters are different compared to the GT, so the calibration to get the same results will need to be different. For example, look on the C&L Calibration Page, you can see how they use different tubes for the same size injectors based on whether you are tuning a GT, Cobra, T-bird, or Taurus SHO.

BTW, no MAF curve I know of is linear, hence why it is a curve. The curve is not by accident. There is some science behind why it is a curve, and not linear like Wideband O2 transfers are.

Next topic...

Compensation done by Closed Loop and Adaptive Learning are for all fueling conditions, not just the MAF's affect on fueling. The EEC is compensating for error in the MAF curve, error in the injector parameters, possible air leaks into the engine, the engine's combustion behavior itself, and even the fuel you are burning (100% gasoline vs E10 or some other variant). People want to treat the fuel trims as though they only reflect inaccuracies in the MAF. When you know the MAF is the source of the majority of your fueling error, that's probably not a bad assumption and using them in this way will get things closer. But as you get the MAF honed in closer, the influence of all the other errors will become more apparent and that's when you start going in circles...tweaks that seem should fix a problem either don't or fix it only for a certain RPM/Load condition, but make some other condition worse.

Does that help?

[heeke]

Thanks a lot for your replies. I think you all said what I thought, the ones that are cal'd for xxlb/hr injectors are not going to report the correct amount of air to the computer. I think that eliminates all the C&L meters. I will look for the 90mm Lightning MAF.

Thanks again
Greg

[mike8675309]

Thanks a lot for your replies. I think you all said what I thought, the ones that are cal'd for xxlb/hr injectors are not going to report the correct amount of air to the computer. I think that eliminates all the C&L meters.

MAF meters don't report the amount of air to a computer. MAF meters return a voltage that can be associated with an amount of air that has passed through it. C&L are probably the easiest MAFs to work with since you typically use your stock sensing element with them, they are simply a housing with an orifice tube. C&L Machines the orifice tube to scale how much air flows over the sense element in proportion to the adjustment being made on injectors. Other MAFS actually have their own electronics and they scale things internally. The OEM electronics are typically more robust.

[AdderMk2]

C&L are probably the easiest MAFs to work with since you typically use your stock sensing element with them, they are simply a housing with an orifice tube.

I beg to differ, I used the "proper flow chart" to input the MAF transfer for my C&L with 30# injectors when I had the 30's on my car. I could NEVER get the car to run right. The only time it would run corectly was when I put the stock maf transfer and injector values back in the car. It was a nightmare to tune because EVERYTHING was skewed. I couldnt get it to idle corectly, RPM's would hang during shifts.. etc etc.

Now I am running the ABU2 LMAF, and from the moment I put it in, set the values and cracked it up. it has ran like a wet dream. SN-95 owners always bitch abouthanging idle issues, and surgine idle issues.... I had none, from the start. And ask mike... my cam is NOT very subtle.

[cgrey8]

I agree that a MAF is just a device that converts a flowrate into a voltage. Sounds simple right? Well, it should be. But like most anything, there are different ways to skin that cat and some people's MAF designs are better than others. But there are two distinct aspects to measuring airflow:

• Mechanical Design
• Electrical Design

C&L's method reuses the stock Ford electronics and only modifies the curve by changing the mechanical design using a calibration tube to change the airflow speed past the Ford electronic's pickup wires. It's a simple change and for the most part, it works.

But the stock electronics design isn't the best. Newer Ford MAFs benefit from better design and are thus better than C&L. The LMAF is one of those newer designs and is an improvement over the 89-95 era MAFs. For most naturally aspirated or draw-thru boosted setups, the LMAF seems to work great. But it is still a stock MAF. It has limitations, mostly in the electronics. For a 90mm air frame, it should be able to measure a LOT more flow than it does. There are 76mm and 80mm aftermarket MAFs that can measure way more than the 90mm LMAF. And the LMAF is known for not working well in blow-thru boosted applications. So for applications that exceed the LMAF's max flow rate and/or the application is a blow-thru, you really need an aftermarket MAF that has a better mechanical and electrical design better suited to those needs.

So while the intention is to convert airflow to voltage, there are different ways to do that, some much better than others. That being said, my C&L 73mm works. The issues I've had with flow inconsistencies existed with the stock 55mm GT MAF. So using the C&L didn't fix anything, but it didn't make things worse. Perhaps a better MAF would've improved things? I don't know. But now that I've dealt with the issues I'm not motivated at all to replace the MAF with a more expensive one just to see.

[Shaker666]

You wanted opinions, so here's my 2¢.

• +1 on 90mm LMAF. Very accurate and I've never needed to adjust the MAF transfer function in my wild combination. Sure there are better electronics out there, but the LMAF is a tried and proven component.
• Stay away from C&L. I've run 2 of their meters with different electronics and while I've been able to get them to perform ok, the amount of tuning required to dial them in is not worth the hassle.
• If your application can work with the limited airflow measurement of the stock 55mm or Cobra 70mm MAF assemblies, they are also tried and proven components.

Do not worry about injector size and how that relates to your MAF calibration. They are 2 completely separate and independent variables. With a tuner (Tweecer, QH, etc.) you'll be able to program the ECU to work with whatever MAF and injectors you choose. +1 on what someone else mentioned about staying away from MAFs that are "calibrated" for a certain flow rate injector. Just make sure you select injectors and a MAF that flows enough with some safety margin for your application.

[2fast4u]

why not look into the "slot style" MAF's ?? Right of the get go...

[cgrey8]

If you have the budget to afford a slot style MAF, I can't think of a reason why you wouldn't jump right to one of the better MAFs. There could be other reasons like limited availability or lack of selection, but I don't know that for a fact.

In the case of the LMAF, yeah it has its limitations, but as long as those limitations don't apply to you, it's difficult to knock it. The LMAF is quite possibly the best bang for the buck.

As for the C&Ls, most people buy C&Ls because they are significantly cheaper than the alternatives mainly because all they are is a machined aluminum frame that reuse the stock electronics. I have a C&L 73mm MAF because I picked it up for cheap on eBay to replace my 55mm stock GT MAF. Almost any MAF would've been an improvement over that POS-restrictor-plate-of-a-MAF. Notice:



Would a more expensive MAF have served me better? I have no clue. I bought the C&L used off eBay back before I got the V8 installed in my truck...before I even had a tuning device. Converting to an LMAF is still an option, but at this point, there's little incentive for me to bother. Compared to the C&L I have, the LMAF wouldn't improve HP by any significant amount. And my tune is setup to handle most all the issues that annoy me. Although if someone wanted to toss me their old LMAF they've out-grown, I'd install it just to see if there is any noticeable difference/improvement over the stock GT and C&L I have. I may find that 90-something % of all the issues I fought early on would've been solved by getting a decent MAF from the get-go. Then again, maybe not. Either way, it'd be an interesting test...one I'd be interested in performing, but just not interested in financing.

[Future303]

Isn't it true that the bigger a MAF is, the less resolution you will have to work with at lower RPM's?

I am considering going to a Lightning MAF from my stocker 70mm MAF. However, my application will probably not exceed 400hp for now, so 90mm may be too much MAF for me, and perhaps 80mm LMAF is a better choice?

[Shaker666]

Isn't it true that the bigger a MAF is, the less resolution you will have to work with at lower RPM's?

I am considering going to a Lightning MAF from my stocker 70mm MAF. However, my application will probably not exceed 400hp for now, so 90mm may be too much MAF for me, and perhaps 80mm LMAF is a better choice?

I had the same concern initially, but after seeing how it's turned out I can say that the LMAF works great at low RPMs and I've not had to touch the transfer function either.

[cgrey8]

Isn't it true that the bigger a MAF is, the less resolution you will have to work with at lower RPM's?...

That is true. However I'm not sure how much it matters. As long as the MAF is properly sized for the engine, it shouldn't be an issue. The MAF curve is curved to help reduce the resolution issue down at the lower parts of the flow range. Because of the curve, at low low rates, small changes in flowrate change the voltage far more than the same difference in flowrate higher up on the curve. So for instance a change from 16 to 18kg/hr produces say a .1v change. However going from 300 to 302kg/hr is barely a blip, if detectable at all by the EEC. But the fact still remains that as the curve has to reach higher, the cruising section (1-2.5v range) does loose some resolution. What I've come to learn though is that the change in resolution as it relates to driveability is negligible. There are too many other variants and fluctuations that affect fueling more than resolution does...at least IMO.

Now where resolution will start to become a problem is at the end of the curve where the curve starts to go vertical. Tiny fluctuations in voltage start translating to HUGE differences in air flow as measured by the EEC that may not be real changes. If the fluctuations get too great in this area, you won't be able to maintain a stable AFR because the EEC is adding and removing fuel based on the jitter of the voltage that may just be noise, not actual changes in flow. To prevent that, don't size a MAF to run right to 5.0v. Size a MAF so that your max flowrate will be in the 4.5-4.7v range so that you stay out of that vertical area and thus maintain decent resolution so you can maintain a fairly stable AFR at those flowrates. If you aim to not exceed say 4.6v, then you'll be fairly guaranteed not to hit anywhere near 5v since it becomes increasingly more difficult to get the voltage to go higher when you get into that range. Said another way, the amount of air it takes to go from 4.6v to 4.7v is much greater than the increase from 4.5v to 4.6v. Likewise getting 4.8v (legitimately) is even more air.

...I am considering going to a Lightning MAF from my stocker 70mm MAF. However, my application will probably not exceed 400hp for now, so 90mm may be too much MAF for me, and perhaps 80mm LMAF is a better choice?

The LMAF may be 90mm, but it is not like aftermarket MAFs that big. There are plenty of 80mm and even 76mm MAFs that can measure flowrates WAY above the 90mm LMAF. What the 90mm gives the LMAF is less restriction compared to those others. While the diameter of the MAF is important, what's far more important is what the flow rate of the MAF at 4.5-4.7v range and that your engine doesn't exceed that and what the voltage is while at cruising.

On the other extreme, you setup a 73mm C&L with a green tube and it can actually measure more airflow than a 90mm LMAF. But why is the LMAF better (besides the LMAF not being a C&L)? Intuitively you just believe it is going to be more suited than the smaller 73mm MAF because it is bigger right? But why if the 73mm can be setup to measure more air? There are a few reasons why the LMAF is better. But I only want to focus on 1 for this example...flow restriction.

Larger orifices can flow more air than smaller ones. We don't need science formulas to justify that statement. Most people know they can blow more air through a straw than one of those plastic coffee stirrers. Likewise you can blow more air through a garden hose than through a straw. Same is going to be true of MAFs. The larger MAF will flow more air. Until air approaches a certain velocity through an orifice, the differential pressure across that orifice isn't significant. However once the airflow is able to produce ~.1"wc differential pressure, the pressure differential is significant...significant in that replacing the MAF with a larger one will produce a lower differential pressure putting it back in the insignificant range, and actually allow more air into the engine. Thus if you upgraded from a 73mm MAF to a 90mm LMAF AND your engine was flowing enough air at WOT to produce a significant differential pressure with the 73mm, then upgrading to a 90mm MAF (or any other size) would increase the output by a good 5-6HP if not more.

However if you did the same upgrade to a stock or nearly stock engine that couldn't produce a significant differential pressure with the 73mm, you probably wouldn't gain more than 1 HP if that. Its like comparing whether you can blow more air through a 1.5" pipe or a 2" pipe. Both are probably so big that your throat is a bigger restriction than the pipes are so going to a bigger pipe isn't going to change things significantly like it did going from the coffee stir to the straw.

Make sense?

Now remember those other differences I mentioned between the 73mm and the LMAF? The other major difference is that the LMAF's curve is contoured differently than the C&L would be. The cruising flowrate area of the curve is lower than the 73mm would be which gives you better resolution in the cruising area and thus better potential driveability. As well, it's also not nearly as vertical at the top-end which gives it superior AFR control as compared to the 73mm at the higher airflow rates, even up near 4.9v. It's a perfect example of how looking at MAX numbers can lead you astray. Ford did such a good job with the LMAF that despite its large airframe and relatively high MAX flowrate, it has better resolution at the ultra-low end (idle flowrates) than most of the older stock MAFs. It truly is a superior MAF.

[decipha]

im sure some one is going to

but i've tuned a few cars where guys just drilled a hole in their intake piping and dropped a sensor in there

never had a problem

[cgrey8]

If you can figure out the curve, that's a valid way to do it and I don't doubt it works OK. The tube of the C&L may stabilize/straighten the air across the pickups a bit. But other than that, it doesn't have to be any more complicated than that. But if I were going to do that, I'd get better electronics than the old 89-93 Mustang MAFs...like for instance the pickup on an LMAF or one of the slot-style MAFs.

[Future303]

Wow! Killer Info!!

Thanks guys!! time to look for a 90mm LMAF, anyone have a nice one for sale? LOL

[cgrey8]

Check eBay.

[AdderMk2]

Wow! Killer Info!!

Thanks guys!! time to look for a 90mm LMAF, anyone have a nice one for sale? LOL

I agree, look on Ebay. Blue Oval Industries sells them for ~$90. Make sure you get the filter adapter and harness adapter. The filter adapter is a minimum. If you want you can go to a junkyard and make your own harness adapter. Cut the MAF plug out of a newer ford.

[cgrey8]

You can usually find an auction or Buy-It-Now sale where the MAF and ring are sold together so you aren't paying shipping twice.

eBay>90mm Lightning MAF & CNC Ring
In a quick search, here's one I found for $125 for the MAF, ring, and s/h.

[heeke]

I just got back from vacation. Thanks for all the info posted.

There is a 80mm Ford MAF on Ebay now:
http://cgi.ebay.com/ebaymotors/ws/eBayI ... fe=sidebar
right now its cheap, does anyone see a reason to avoid this?

The best second option I see is the Blue Oval 90mm MAF with filter adapter and filter for $150 here. Since I am converting I think I will need all of this anyway...
http://cgi.ebay.com/ebaymotors/Ford-Rac ... ccessories

Thanks again, GREAT info.

[AdderMk2]

I just got back from vacation. Thanks for all the info posted.

There is a 80mm Ford MAF on Ebay now:
http://cgi.ebay.com/ebaymotors/ws/eBayI ... fe=sidebar
right now its cheap, does anyone see a reason to avoid this?

The best second option I see is the Blue Oval 90mm MAF with filter adapter and filter for $150 here. Since I am converting I think I will need all of this anyway...
http://cgi.ebay.com/ebaymotors/Ford-Rac ... ccessories

Thanks again, GREAT info.

that 80mm MAF that you linked would do you no good at all. It flows 791KG/hr at 5v... I would peg that in my car at about 3800-4000 RPM...

just get the 90mm LMAF

also, your new intake tubng can be bought from www.intakehoses.com Save yourself some money and fab your own CAI.

[Lucky]

Is the 90mm LMAF a direct replacement for 80mm units used in 96-98 Mustangs or does it have a different bolt pattern and larger tubing connector ?

[AdderMk2]

Is the 90mm LMAF a direct replacement for 80mm units used in 96-98 Mustangs or does it have a different bolt pattern and larger tubing connector ?

not even close to being a direct replacement

[Lucky]

that being the case...

I just cut the center tube out of my 80mm MAF, honed it smooth and chucked the screen. I expected to be back near square one with my tune but amazingly it still runs pretty great !
It's breaking up a little near 7000RPM but over all still drivable.

Time to redo the MAF Transfer but datalogging is on the fritz