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Topic: 19/24 lb MAF? (Read 4087 times) previous topic - next topic

19/24 lb MAF?

Hi guys,

I've finally completed my MAF conversion yesterday. I had one of those OEM 70mm '94 TBird SC meters and (according to the stangnet website) found a sensor from a '93 Lincoln Towncar in the junkyard.  It's the F2VF-12B579-A1A (not -AA).    I know you're not supposed to mix and match but apparently these work together.  In any case,  everything worked and the conversion fixed my last issue which was a slight lugging at lowest throttle.  Now it is very smooth. 

The question is,  on EBAY,  they advertise these meters with the  F2VF-12B579-A1A sensor as 19/24 lb MAF.

http://www.ebay.com/itm/70mm-mass-air-flow-94-95-Mustang-GT-Cobra-19-24lb-MAF-/281480716890?pt=Motors_Car_Truck_Parts_Accessories&hash=item41898ee25a&vxp=mtr



What does that mean?  the sensor is the same as mine (F2VF-12B579-A1A)  and the meter is the same (although without the ) as the SC.  Does that mean that I can run 24lb injectors without changing anything?    or is that bull pucky?
'88 Bird 5.0, TW 170s, HO cam, Scorpion rockers, Explorer intake 70mm TB/EGR, MAF conversion, 24# injectors, 8.8 3.73 disc rear end swap, console swap, leather seats, 11" front discs, 15-1 rack, TC springs all around, x-pipe, BBK headers,  welded sub-frame, unlocked digital speedo.

19/24 lb MAF?

Reply #1 –
No. You can just run 19lb injectors. The MAF in question is the same between the 5.0 GT (19lb injectors) and the 5.0 Cobra (24lb injectors). All 94-95 Mustangs with 5.0 V8s use the same MAF meter. The injector size calibration is set in the computer NOT by the MAF. All factory Ford MAF meters are like this. They are NOT calibrated for an injector size. Instead it is done in the computer. Aftermarket MAF meters are calibrated for an injector size by changing the amount of air the MAF meter sees, thereby causing the computer to fire the injectors for the correct length of time even though they may be 24lb or 30lb injectors.

So to straighten this out:

Factory MAF meters ARE NOT CALIBRATED FOR A PARTICULAR SIZE INJECTOR. ONLY AFTERMARKET MAF METERS ARE CALIBRATED FOR A SPECIFIC SIZE INJECTOR.

So if you want to run 24lb injectors you need a MAF calibrated for 24lb injectors or the computer tuned. The F2VF MAF will only work with the stock computer and stock 19lb injectors when used with an A9P/A9L computer.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

19/24 lb MAF?

Reply #2 –
Thanks for the quick, concise reply TJ.  I didn't get that until now.  The aftermarket MAFs spoof the stock computer to correctly allocate timing and duration for the larger injectors.  So when buying an aftermarket MAF,  I would assume you would have to purchase one that works with your computer (in my case A9P).  Or like you said,  get a tune on the stock computer.

Are those Bama tunes any good?
'88 Bird 5.0, TW 170s, HO cam, Scorpion rockers, Explorer intake 70mm TB/EGR, MAF conversion, 24# injectors, 8.8 3.73 disc rear end swap, console swap, leather seats, 11" front discs, 15-1 rack, TC springs all around, x-pipe, BBK headers,  welded sub-frame, unlocked digital speedo.

19/24 lb MAF?

Reply #3 –
When buying an aftermarket MAF yes you want one that works with an 89-93 Mustang 5.0 computer. The A9L/A9P use the same MAF so as long as it's listed as working with an 89-93 Mustang 5.0 it will work fine.

As far as a Bama tune I've heard mixed reviews on them. Probably best to find someone locally who can tune your car.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

19/24 lb MAF?

Reply #4 –
Not only does the EEC determine the size of the injector but it is also loaded with the transfer function for the MAF that comes with the car from the factory. For example the stock Fox Mustang MAF is a 55mm which will flow up to 835 kg/hr.  A 70mm MAF will flow about 960 kg/hr so you can see where changing from one OEM MAF to another without compensating for the transfer function differences between them either by a "calibrated" MAF or via tuning the EEC. If you don't do this it will cause a lean condition as you will be bringing in more air per volt (remember the EEC likes 0 to 5 volt signals) than what the EEC is expecting.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

19/24 lb MAF?

Reply #5 –
Quote from: Aerocoupe;443910
Not only does the EEC determine the size of the injector but it is also loaded with the transfer function for the MAF that comes with the car from the factory. For example the stock Fox Mustang MAF is a 55mm which will flow up to 835 kg/hr.  A 70mm MAF will flow about 960 kg/hr so you can see where changing from one OEM MAF to another without compensating for the transfer function differences between them either by a "calibrated" MAF or via tuning the EEC. If you don't do this it will cause a lean condition as you will be bringing in more air per volt (remember the EEC likes 0 to 5 volt signals) than what the EEC is expecting.

Darren

Sounds like I'm running lean right now then.  I think I'll get the 24lb after market MAF, put in the 24lb injectors and then get a tune.  The tune in my area costs around $500.  That is a big chunk of change -- is that what everyone's paying?
'88 Bird 5.0, TW 170s, HO cam, Scorpion rockers, Explorer intake 70mm TB/EGR, MAF conversion, 24# injectors, 8.8 3.73 disc rear end swap, console swap, leather seats, 11" front discs, 15-1 rack, TC springs all around, x-pipe, BBK headers,  welded sub-frame, unlocked digital speedo.

19/24 lb MAF?

Reply #6 –
I've got 24lb injectors and an aftermarket calibrated MAF for 24lb injectors with no tune. The idea of a calibrated MAF is that you won't need a tune on mild combinations.

If you get a tune you can run any MAF you want. For example you could run a Lightning 90mm MAF with 24lb injectors with a tune. Without one you couldn't.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

19/24 lb MAF?

Reply #7 –
I ran mine for years with a calibrated Pro-M (IMO one of the best calibrated MAF out there) with 24 lb/hr injectors with a similar combo to yours with no chip and it ran great. You just have to make sure your tune up is good, timing is checked and set, fuel pressure is on the money, and your electrical system is in good shape. With regards to the electrical system I am mentioning this as the EEC on my Coupe is grounded just behind the battery to the inner apr0n. The engine to chassis ground is also grounded here. The engine to chassis ground on my car got corroded internally (could not see it due to the insulation around the copper wires) and the car ran intermittently like dog poo. After a lot of testing and reading online I finally figured it out and replaced this wire. Let me tell you all kinds of problems went away.

In general an SCT Dyno tuned switch chip will run about $500. If you bring them the car with a shiznitty tune up, fuel pressure incorrectly set, timing incorrectly set the it usually costs more.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

19/24 lb MAF?

Reply #8 –
Ok.  Maybe I can save the $500 and just by a good MAF.  Thanks for the advice!
'88 Bird 5.0, TW 170s, HO cam, Scorpion rockers, Explorer intake 70mm TB/EGR, MAF conversion, 24# injectors, 8.8 3.73 disc rear end swap, console swap, leather seats, 11" front discs, 15-1 rack, TC springs all around, x-pipe, BBK headers,  welded sub-frame, unlocked digital speedo.

19/24 lb MAF?

Reply #9 –
Pro-M and PMAS MAF meters have a good reputation. Either one is a good bet. I've been thinking of switching from the C&L 76mm MAF on my Thunderbird to an 80mm PMAS MAF for a couple of years now. I've never had any drive-ability issues with the C&L MAF so I've never really had a reason to switch it out.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

19/24 lb MAF?

Reply #10 –
Over the weekend I exchanged my 4-hole 19# injectors for pintle-type 24# injectors (from a Lincoln Mark VIII).  I bought a C&L meter from Corral (blue tube) and using the stock Mustang sensor.  It's runs really well, idles perfectly and the throttle is super-responsive.  My AOD leaves a bit to be desired but that is a different story. 

My question is,  I've noticed that my MPG (digital dash) is now reading at least 3-5 MPG higher than it was before the MAF and 24# injector swap.  Is that expected because I'm spoofing the computer into putting out shorter bursts of fuel?
'88 Bird 5.0, TW 170s, HO cam, Scorpion rockers, Explorer intake 70mm TB/EGR, MAF conversion, 24# injectors, 8.8 3.73 disc rear end swap, console swap, leather seats, 11" front discs, 15-1 rack, TC springs all around, x-pipe, BBK headers,  welded sub-frame, unlocked digital speedo.

19/24 lb MAF?

Reply #11 –
Quote from: marianadeeps;444780
Over the weekend I exchanged my 4-hole 19# injectors for pintle-type 24# injectors (from a Lincoln Mark VIII).  I bought a C&L meter from Corral (blue tube) and using the stock Mustang sensor.  It's runs really well, idles perfectly and the throttle is super-responsive.  My AOD leaves a bit to be desired but that is a different story. 

My question is,  I've noticed that my MPG (digital dash) is now reading at least 3-5 MPG higher than it was before the MAF and 24# injector swap.  Is that expected because I'm spoofing the computer into putting out shorter bursts of fuel?

Yep. The trip computer will be a bit off.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

19/24 lb MAF?

Reply #12 –
Ah ok.  thanks.
'88 Bird 5.0, TW 170s, HO cam, Scorpion rockers, Explorer intake 70mm TB/EGR, MAF conversion, 24# injectors, 8.8 3.73 disc rear end swap, console swap, leather seats, 11" front discs, 15-1 rack, TC springs all around, x-pipe, BBK headers,  welded sub-frame, unlocked digital speedo.