I remember reading about old school methods when air flow meters were maxed out involving using air bypass pipes around the MAF. I've never done it myself, but I have fitted larger ones, which is basically the same thing. The air flow meter (at least if its a hot wire type, others are similar to varying degrees) doesn't really care what's going on around it, it just measures the speed of air travelling over the sensor element. If you increase the gap around it, it still measures the speed of the air going in the engine, it just scales up with the size of the pipe. This effectively increases the headroom of the sensor, at some sacrifice to resolution. Much the same as altering the table headers would.
Maf senors don't read the speed of airflow. As air rushes past the hotwire, the resistance of the wire decreases and more voltage is applied to it in order to maintain its temperature. That voltage corresponds to a cell in the maf scaling table which allows the ecu to estimate the amount of airflow passing the sensor. When going to a larger maf housing, the voltage change would stay the same but the maf scaling table would still be calibrated for the stock intake design. This will throw off the airflow and fuel calculation. The fueling inaccuracy can by verified by logging the short + long term fuel trim. The larger housing will increase the maf headroom at the cost of resolution, but it will still require rescaling of the maf table for airflow/fueling to be correct.
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I remember reading about old school methods when air flow meters were maxed out involving using air bypass pipes around the MAF. I've never done it myself, but I have fitted larger ones, which is basically the same thing.
The air flow meter (at least if its a hot wire type, others are similar to varying degrees) doesn't really care what's going on around it, it just measures the speed of air travelling over the sensor element.
If you increase the gap around it, it still measures the speed of the air going in the engine, it just scales up with the size of the pipe. This effectively increases the headroom of the sensor, at some sacrifice to resolution. Much the same as altering the table headers would.
Maf senors don't read the speed of airflow. As air rushes past the hotwire, the resistance of the wire decreases and more voltage is applied to it in order to maintain its temperature. That voltage corresponds to a cell in the maf scaling table which allows the ecu to estimate the amount of airflow passing the sensor.
When going to a larger maf housing, the voltage change would stay the same but the maf scaling table would still be calibrated for the stock intake design. This will throw off the airflow and fuel calculation. The fueling inaccuracy can by verified by logging the short + long term fuel trim. The larger housing will increase the maf headroom at the cost of resolution, but it will still require rescaling of the maf table for airflow/fueling to be correct.
So I can say that we still can use the MAF with FI cars or better we switch to SD?