dual MAF? is there such a thing?

[NJB71]

I am wondering, I have seen MAF that say for 19lbs and 24lbs? are there MAFs that are dual calibrated? I just realized going back over my ebay history, and I bought just that type....a dual use MAF...i have 24lbs injectors .....

 

[Broncobowsher]

The MAF does not know nor care what size injecters you have.
The MAF (Mass Air Flow) looks at how much air is going into the engine and gives a very precise voltage to the computer. The computer looks at the voltage, then looks at the programming (that matches the MAF output) and then knows how much air is engering the engine. Then looks at the injector size (also a program feature) and figures how long to squirt the injecter.

Your aftermarket MAF works on the old computer "garbage in, garbage out" principal. You lie about how much air is going in and the computer give false outputs on how long to fir the injecters. On a race engine that uses fixed timing tables at full throttle (the A9 series for example) then the computer calculating load is not an issue. But in daily driving where the computer is setting the ignition curve the timing will be messed up. the computer can't accurately calculate the load because it does not have accurate numbers about how much air is enering the engine.

So to have a MAF that can do 2 different injecter sizes is not happening. Not unless you have 2 settings on the computer. Some of the aftermarket chips have a multi postion switch that if programmed correctly you could do such a trick. but at that point you might as well just program the computer correctly and not have the issues.

 

[NJB71]

The MAF does not know nor care what size injecters you have.
The MAF (Mass Air Flow) looks at how much air is going into the engine and gives a very precise voltage to the computer. The computer looks at the voltage, then looks at the programming (that matches the MAF output) and then knows how much air is engering the engine. Then looks at the injector size (also a program feature) and figures how long to squirt the injecter.

Your aftermarket MAF works on the old computer "garbage in, garbage out" principal. You lie about how much air is going in and the computer give false outputs on how long to fir the injecters. On a race engine that uses fixed timing tables at full throttle (the A9 series for example) then the computer calculating load is not an issue. But in daily driving where the computer is setting the ignition curve the timing will be messed up. the computer can't accurately calculate the load because it does not have accurate numbers about how much air is enering the engine.

So to have a MAF that can do 2 different injecter sizes is not happening. Not unless you have 2 settings on the computer. Some of the aftermarket chips have a multi postion switch that if programmed correctly you could do such a trick. but at that point you might as well just program the computer correctly and not have the issues.

i GOT SAY, i HAVE HAD SOME IDLEING ISSUES, LEAN CODES, RE DID (sorry about caps) base timing, base idle, tps etc...I have a a3m1, a burned sct6600 program piggyback(for 24lbs and a maf calibrated for 24lbs), starting to wonder if the dual MAF isnt all that its cracked up to be, sounds like you suggest that, and maybe there lies my problem...i have been thinking my timing has been screwy all along

 

[57baja]

I am wondering, I have seen MAF that say for 19lbs and 24lbs? are there MAFs that are dual calibrated? I just realized going back over my ebay history, and I bought just that type....a dual use MAF...i have 24lbs injectors .....

I have a maf from Aabco they program it for your injector size but you have 10 settings on the maf that you can program yourself with their software. It's a little pricey but if you plan on changing your motor combo you don't have to keep buying a maf for your injector size. It will work on a 5.0 or even the newer mustangs. There is a good write up in 5.0 magazine or just go to AndersonFordMotorsport website they sell it in different sizes I bought a 85mm for $389.

 

[Bronco_69]

I have a maf from Aabco they program it for your injector size but you have 10 settings on the maf that you can program yourself with their software. It's a little pricey but if you plan on changing your motor combo you don't have to keep buying a maf for your injector size. It will work on a 5.0 or even the newer mustangs. There is a good write up in 5.0 magazine or just go to AndersonFordMotorsport website they sell it in different sizes I bought a 85mm for $389.

sorry to say this but that is BAD advice for the OP.


with the OP combo it will never run 100% right without a tune. you may get it bearable but that will be about it.

the best advice for him would be to buy a 90mm OEM lighting MAF and find a good custom dyno tuner. NO MAIL ORDER TUNE WILL EVER GET IT RIGHT. i put that in caps for a reason.


with the set up on your motor throwing hack parts at it (dual MAF's etc) will not correct the tunning in the ECM. BW's post sums it up pretty well.


i think i mentioned it before, but if you have some stock 19's put them in with a stock mass air meter and see how it idles and drives. I know yuor engine is not stock but the 19's will be good for about 80% of your power. (dont go drag racing with it). if that runs well, then invest in the lightning maff and a custom tune.

 

[KyleQ]

My Pro-M MAF is calibrated to whatever specific lb/hr injector I am running - so to a point they are tunable. Aftermarket MAF's must be matched to the injector they are calibrated to run - otherwise it will either run rich or lean.

Case and point I'll be running 42lb/hr injectors with my calibrated MAF to a 100% stock Mustang computer.

 

[Bronco_69]

Case and point I'll be running 42lb/hr injectors with my calibrated MAF to a 100% stock Mustang computer.

but your idle quality will suck and be rich. at idle the mass air meter does not control the injectors, the computer has a set injector pulse. therefore your 42's will be injecting at the rate same pulse as the stock 19's, dumping twice as much fuel at idle.

a cheaper lightning maf and tune would fix it and perform better.

 

[Broncobowsher]

My Pro-M MAF is calibrated to whatever specific lb/hr injector I am running...

There is no injector calibration in the MAF. the MAF only reads the amount of air entering the engine. It has no idea what the computer will do with that information.

You think you are going to run 42s on a stock computer? Well it may run, but not right. Here are a few things going on.
at idle the MAF must tell the computer that less then half the air that is entering the engine. The computer has very little programming for such low values, if any. If you can get a small block to idle on half less then half the air that it normally takes to idle, well the engine will stall. There is a very good chance you could throw a MAF voltage is low code.
the other biggy, your timing is going to be completely jacked during normal cruise. All the computer controlled timing is based on load. Load is calculated by how much air is going into the engine. For a drag racer there is a great thing about the A9 computers, at wide open throttle it goes into fixed ignition tables. but during normal driving the timing is based on a load. Since the computer is only seeing a less then half the air that is really entering the engine it thinks the load is very light. So it cranks up the timing. You are going to have massive knock issues due to too much timing at cruise. But strangely at full throtttle it will be just fine.
If building a drag racer, things will be just fine. If you want street manors, you will be so screwed.

 

[av bronco]

Your MAF should have come with paperwork that tells you flow values, with that info your tuner can adjust the chip or if you have a Tweecar or Moates Quarterhorse you can do it yourself. You need a wideband to see just where your at tho if your gonna tune it yourself.

 

[NJB71]

but your idle quality will suck and be rich. at idle the mass air meter does not control the injectors, the computer has a set injector pulse. therefore your 42's will be injecting at the rate same pulse as the stock 19's, dumping twice as much fuel at idle.

a cheaper lightning maf and tune would fix it and perform better.

I agree, swapping MAF 24lbs only 80mm lightning, and seeing dnyo guy this weekend-its strande, surge comes when cold, warms up in park and i drive her-drives great, but when i park after while of driving it will surge, even when engine warm.... dyno-retune -better then frustration

 

[NJB71]

Your MAF should have come with paperwork that tells you flow values, with that info your tuner can adjust the chip or if you have a Tweecar or Moates Quarterhorse you can do it yourself. You need a wideband to see just where your at tho if your gonna tune it yourself.

you imply i bought a new...hahahaha, everything except the harness on the swap, was used(injectors were remanned)the MAF is from an ebay seller, and I was a knuckle head cause i paid 70bucks, had i spent the $ on new who knows? no surge?....still questioning my choice, cause it didnt seem right dual MAF....so now i just spent $100 more on a 24lbs calibrated 80mm MAF, and hopefully tuned this weekend

 

[73azbronco]

whats you motor, bone stock 5.0? If not, get thee to a dyno and have a chip made for your combo.

 

[NJB71]

whats you motor, bone stock 5.0? If not, get thee to a dyno and have a chip made for your combo.

nope, 302 roller, 185cc/60cc heads, e303cam, etc,etc(ATK performance crate)-i did have a jms burn a sct6600 to piggyback, so with driveline, engine, exhaust, etc and new top end components i thought the chip would compensate, no such luck, was thinking swap MAF(which i am) but i am getting dyno'ed

 

[av bronco]

You might get the values from the manufacter of the MAF, also there's a website that has a template you can print out & give to your tuner, but he probably already has it.

 

[57baja]

sorry to say this but that is BAD advice for the OP.


with the OP combo it will never run 100% right without a tune. you may get it bearable but that will be about it.

the best advice for him would be to buy a 90mm OEM lighting MAF and find a good custom dyno tuner. NO MAIL ORDER TUNE WILL EVER GET IT RIGHT. i put that in caps for a reason.


with the set up on your motor throwing hack parts at it (dual MAF's etc) will not correct the tunning in the ECM. BW's post sums it up pretty well.


i think i mentioned it before, but if you have some stock 19's put them in with a stock mass air meter and see how it idles and drives. I know yuor engine is not stock but the 19's will be good for about 80% of your power. (dont go drag racing with it). if that runs well, then invest in the lightning maff and a custom tune.

He asked if there was a dual calibrated maf. I just said I have a maf with available software so you can run different injectors without changing your maf you program the maf tables with a laptop. I did not say anything about the computer or a tune just gave him an answer on his original question