Adding to my crazyness....
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From: Ft Hood, TX Yeehaw!
The 03 Mustang Cobra and the Later Ford Lightnings have the correct style Maf that we need(5 Wire, Hotwire with integrated IAT sensor). They are plenty big enough but would most likely have a totally different voltage curve than our maf. IMHO not worth the gains for the hours of tuning it would take. The VK45 might have a bigger Maf but no one has tried one.
Originally Posted by k_hojnacki
So, with that figure in mind, is there a larger MAF sensor, say 3" from any other Nissan of Infiniti that would also fit our VQ engines that might correct this issue? And more specifically, from the highly technical community, what size MAF sensor should we be looking at for a 75.5mm housing? Is there a 2.86 inch or comparable MAF sensor available?
After looking on the FX forums, which I was completely impressed that they mod their cars (suv's) as much as ours, I wondered if anyone here had both a G and an FX45 that they could compare the MAF sensors and housings? A 5% increase coupled with additional mods (such as Mrev2) may really increase throttle response and improve mid-range power. And if they can be off the shelf parts that would make it that much better. JMHO
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From: Ft Hood, TX Yeehaw!
How would you tune it? You would instantly run lean if all you did was install a bigger maf.
Originally Posted by k_hojnacki
After looking on the FX forums, which I was completely impressed that they mod their cars (suv's) as much as ours, I wondered if anyone here had both a G and an FX45 that they could compare the MAF sensors and housings? A 5% increase coupled with additional mods (such as Mrev2) may really increase throttle response and improve mid-range power. And if they can be off the shelf parts that would make it that much better. JMHO
Again, I am very new to this type of car (my experience is with older european/american muscle cars) so excuse my naivite. I was under the impression that if the MAF housing and the MAF sensor were larger but the air velocity and AF ration was equivelant to the origional one but higher in quanity, the on board computer would calibrate correctly the new volume. I understand using the UTEC and other add on computer to compensate for an imbalance or fine tuning but if there is "balance" (lack of a better term) of these critical elements, I was under the impression that the on board could compensate correctly. Ahhh so much to still learn!
Originally Posted by djniknala
How would you tune it? You would instantly run lean if all you did was install a bigger maf.
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From: Ft Hood, TX Yeehaw!
The larger maf and/or different housing would throw of AF ratio because the Air(in AF ratio) would be higher than the Fuel because the car would think it is getting less air than it is. The car can make up for this in light and part throttle circumstances because it is reading the Oxygen sensors in the exhaust to achieve ~14.7 AF ratio. When full throttle it goes into open loop and no longer reads the sensors(because they are inaccurate at anything except around 14.7) and instead of your car being 13.0:1 AF ratio it would go much leaner with the larger housing and probably have knock and detonation.
Originally Posted by k_hojnacki
Again, I am very new to this type of car (my experience is with older european/american muscle cars) so excuse my naivite. I was under the impression that if the MAF housing and the MAF sensor were larger but the air velocity and AF ration was equivelant to the origional one but higher in quanity, the on board computer would calibrate correctly the new volume. I understand using the UTEC and other add on computer to compensate for an imbalance or fine tuning but if there is "balance" (lack of a better term) of these critical elements, I was under the impression that the on board could compensate correctly. Ahhh so much to still learn!
Originally Posted by djniknala
The larger maf and/or different housing would throw of AF ratio because the Air(in AF ratio) would be higher than the Fuel because the car would think it is getting less air than it is. The car can make up for this in light and part throttle circumstances because it is reading the Oxygen sensors in the exhaust to achieve ~14.7 AF ratio. When full throttle it goes into open loop and no longer reads the sensors(because they are inaccurate at anything except around 14.7) and instead of your car being 13.0:1 AF ratio it would go much leaner with the larger housing and probably have knock and detonation.
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From: Ft Hood, TX Yeehaw!
If you read this section http://auto.howstuffworks.com/fuel-injection.htm it's a pretty in depth look at the fuel injection systems. It mentions MAF and MAP(which we don't use) and metering air. If you search around the site you'll find more good info as well like different types of air meters and exactly how maf's work.
Originally Posted by k_hojnacki
Ok That makes sense. So the UTEC overrides this issue by increasing the the fuel suppy in the A/F circuit? or does its program correct the on board in some way? Any suggestions for good reading materials on this subject or more importantly how the newer computers and fuel injection systems function? Like I said, I come from the carb world. And Thanks for the explaination!
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From: Ft Hood, TX Yeehaw!
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From: Jacksonville, FL
Originally Posted by djniknala
If you read this section http://auto.howstuffworks.com/fuel-injection.htm it's a pretty in depth look at the fuel injection systems. It mentions MAF and MAP(which we don't use) and metering air. If you search around the site you'll find more good info as well like different types of air meters and exactly how maf's work.
Ohh and I actually thought u were smart!!!
I know your secrets now 
