Ford 80mm MAF Install
More pictures will be coming soon!
MAF & Injector Primer
The little "black box" on top of your factory meter is often thought to be the heart of the MAF/injector relationship. The fact of the matter is that the black box on top of your meter looks suprisingly like every other Ford meter out there. There is a reason for this and that is because they are the same. They output the same voltage level and curve as any other Ford MAF sensor. It's the way that the computer interprets the signal that makes the difference.
When Ford engineers are designing the EEC for a specific engine, they take into account the flow capability of the meter. They then program the computer to recognize the signal from the MAF to represent that much air flow into the motor. As an Example:
On a stock 5.0 equipped Mustang, there is a 55mm MAF meter. The computer has been programmed to "know" that the MAF is that size. So, if "x" volts are coming out of the MAF sensor, the computer "knows" that it corresponds to "y" Kilograms of air passing through the meter(entering the motor). The computer then calculates the amount of fuel needed to support this incoming air and pulses the injectors to get that amount. There is much more to this (i.e. input from other sensors), but that is the basic way the system works.
What happens when you add a larger MAF meter, you ask? Well, for one, you increase the amount of air coming into the engine. BUT, the computer doesn't know that this change has occured, so it still believes that the engine is operating under the conditions described above. To continue our example from above, if you put a Ford 80mm MAF with the stock sensor on our example car, this is what will happen: The MAF sensor will still output "x" volts as it did before. And the computer will still think that "y" Kg of air are entering the motor and will figure and add the same amount of fuel. But, what's actually happening is the motor is bringing in more air than what the computer realizes (due to the larger diameter meter) and a lean condition is created. Most times, at part-throttle driving on mildly-modified cars, the O2 sensors will recognize the lean condition and the EEC will be able to compensate for it. BUT, at wide-open-throttle, the O2 sensors are ignored and the fuel delivery is calculated solely on the MAF signal. Uh ohh! :-) This is where power adder and serious NA cars can run into BIG trouble. That is why re-calibrating the meter or re-progamming the EEC is necessary.
There are three popular ways to add a larger MAF/larger injectors to your Mustang. They are:
The first is one is the least accurate of the three, and also the cheapest. This is the system used in the Vortech/C&L line of aftermarket meters. What it does is change the size of the samling tube which changes the amount of air flowing through it. What this does is change the voltage that the sensor outputs because the sensor "thinks" that a different amount of air is going through the entire meter than what actually is. One of the most popular mods on a Mustang is to add larger fuel inectors. This is how the "re-calibrated" MAF meters "trick" the EEC into operating with the larger injectors:
When the EEC sees a signal from the MAF and calculates the necessary fuel, it does so using the size injector originally installed on the car (19#/hr in most cases). If you were to just add some larger injectors to the car, the EEC would figure the exact same pulse width for the injectors as it did with the 19#/hr. With a bigger injector, the same opening time equals more flow, and the car would run rich. What the aftermarket companies have done is to "trick" the EEC into thinking there is LESS air coming into the engine than there really is. This way, the EEC automatically shortenns the pulse width (read: less fuel) and your monster injectors don't make the car run rich!
Anyway, the second method of tricking the EEC is to change the voltage values coming out of the MAF sensor. The C&L/Vortech does this by changing the amount of airflow the sensor sees, but the method used by Pro-Flow, Inc actually changes the little black box and leaves your meter intact. This method is far more accurate than method #1, but still has it's limitations.
The final way to do it is to actually re-program your EEC to think that it came with the bigger MAF meter and injectors from the factory. This way is more accurate than either of the other two, but has it's limitations in forced induction applications due to the fact that the meter can be "pegged" by flowing more air than the sensor is designed to read.
Well, that just about does it for my MAF & Injector primer! If you have any other questions, feel free to drop me an e-mail. And now..............
All this will amount to a MAF that will flow right on par with the Pro-M 77mm. And can also save you a lot of money over the $400 for a Pro-M model! Good luck and If you have any questions feel free to e-mail me at the below address.
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