24lb Mass Air Meter Questions......any Junkyard Swaps?

BKM48198

15 Year Member
Jun 7, 2008
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Ypsilanti, Michigan
I have a 70mm Mass air meter calibrated for 19lb injectors but plan on going up to 24lb injectors, did any vehicles come stock with 24lb injectors where the mass air meter is compatible with a Fox body? I do know the 24lb injectors came on Navigators and some trucks, just not sure about the mass air meter.
 
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I have a 70mm Mass air meter calibrated for 19lb injectors but plan on going up to 24lb injectors, did any vehicles come stock with 24lb injectors where the mass air meter is compatible with a Fox body? I do know the 24lb injectors came on Navigators and some trucks, just not sure about the mass air meter.

There are no factory meters that can be installed that will allow you to run a larger injector that stock. period. The EEC logic has a defined curve programmed into it known as the "Mass air transfer function". This table tells the ECM what each voltage output from the MAF equates to. Factory MAF's are not "calibrated" they simply put out a signal and the ECM interprets it. This "mass air transfer function" can be changed, which allows you to run different meters (like my HPX, or an LMAF.. etc etc etc).

If you would like a good, cheap, sure fire way to run those 24# injectors, and don't want to buy an expensive aftermarket maf, PM me.
 
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I didn't think there were any that would work for 24# injectors but wanted to check, I found an older Pro-Flow meter, 75mm bullet for $50, same as the Pro-M meter but Pro Flow either changed their name or was bought out, Pro-M says they do recalibrate the Pro-Flow meters if there are any problems with it. Even if I had to send it for a recal. I'd be saving 1/2 off what they sell for new. Recal is $100, new they sell for $299.
 
I used a slot meter from an 05+ mustang on my last build, I have a qh to change the maf transfer though. Using a high flow hpx on my next build.
Im glad some brought this up. The HPX conversion is super simple. If the 05+ is a 6 wire maf plug, then using an HPX should be a drop in swap... aside from setting the transfer function. I personally use a Power Adder Solutions HPX in my car.
 
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Im glad some brought this up. The HPX conversion is super simple. If the 05+ is a 6 wire maf plug, then using an HPX should be a drop in swap... aside from setting the transfer function. I personally use a Power Adder Solutions HPX in my car.
Yes it is the same plug, unfortunately I had this setup 2 vehicles ago so it is not in my current vehicle. So will have to wire the plug into this car. I think I only used 4 of 6 wires when I did the conversion. The 05 mustang sensor I had to use a 3.5" tube to get the sensor not to peg. But the hpx I think is good for the 3" tube because it is high flow. I have had all the stuff to turbo my car for about 2 years now. Just haven't had time to get it on the car. Doing a gt40, explorer intake and tfs-1 swap right now.. Maybe next winter
 
Im
I have a 70mm Mass air meter calibrated for 19lb injectors but plan on going up to 24lb injectors, did any vehicles come stock with 24lb injectors where the mass air meter is compatible with a Fox body? I do know the 24lb injectors came on Navigators and some trucks, just not sure about the mass air meter.[/QUOT I'm runnin a 98 cobra mass air that's calibrated to my 24lb injectors on my 91 fox, works good. I was told it couldn't be done but called jegs, worse case is a rough idle as if it is cammed. But since the computer isn't actually calibrated for this it actually runs rich an that's a 80mm mass air, but until I can get a bigger one it's fine. I would recommend a cold air intake so you have more air so it want run so rich.
 
I'm runnin 24lb injectors with a 98 cobra mass air that's calibrated for them. Was told it couldn't be done but tried it and it worked, yes you are limited to certain things you can do without a tune but these foxes aren't as sensitive as a lot think, I also have gt40 intake, 65mm tb cold air intake and egr delete.
 
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The 1993 Cobra came from the factory with 24 Lb Injectors, if you use the EEC and Meter from the 93 Cobra then you can use the 24 Lb injectors without a tune or and aftermarket meters.
 
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There are no factory meters that can be installed that will allow you to run a larger injector that stock. period. The EEC logic has a defined curve programmed into it known as the "Mass air transfer function". This table tells the ECM what each voltage output from the MAF equates to. Factory MAF's are not "calibrated" they simply put out a signal and the ECM interprets it. This "mass air transfer function" can be changed, which allows you to run different meters (like my HPX, or an LMAF.. etc etc etc).

If you would like a good, cheap, sure fire way to run those 24# injectors, and don't want to buy an expensive aftermarket maf, PM me.
Yeah, what he said... In laymans terms: An oem maf will work w any injector size. The maf "calibrating" is done w the computer via tune. The advantage of aftermarket "calibrated" maf's is the larger size so more air can go through.
That being said, @BKM48198 I know you sold them but switching to 24lb injectors wouldn't/won't gain you anymore power, you might even lose a little. Therefore one couldn't justify the cost of either an aftermarket "calibrated" maf or a tune to make it work.
 
I sold the 24lb meter and injectors and bought some 1.7 roller rockers and a 255lph fuel pump, now I'm looking for a higher stall torque convertor for the car.
What cylinder heads do you have?
*Edit* I just read your post on the tq converter. Since you have an explorer motor 24 lb injectors plus a tune would probably be worth it. A little on the high side I know but you'd get some bang for your buck.
 
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might want to PM me before making that purchase.
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I'm going to see how it does with the 255lph fuel pump and rebuild the injectors. I had bought a75mm Pro Flow Technologies ( Pro-M) Bullet meter and 24lb blue injectors because I found a GREAT deal on Craigslist $65 for meter, injectors and rebuild kit, but sold them to get the fuel pump and 1.7 crane roller rockers. I don't plan on any power adders for the car so the 19lb parts should be enough to support the HP my engine will make.