What is Alpha n bmw?

Alpha N is the term used by the DME manufacturers to describe a mode of operation. Most German vechicles are designed with an Air Flow Sensor (aka MAF) to provide optimal driveability and clean emmissions control. Removing the MAF on most BMWs forces the DME to operate in Alpha N mode.

What is Alpha n fuel injection?

Alpha-N. Metering style is the strategy the ECU uses to measure airflow and calculate fuel requirements. A Fuel Injection System compares airflow, engine rpm, and other sensor information in the Fuel Map. It uses that information to determine how much fuel is needed at the given time.

How do I tune my ITBs?

The most time effective way of tuning for ITBs is to perform dyno runs at a constant throttle opening, matching the column index TPS values. Note that the tuning range of throttle opening and rpm will depend on the dyno – but generally you can tune the bulk of the fuel table this way.

What does speed density mean?

Speed density systems count on air pressure (as opposed to air flow) and engine speed (rpm) to compute fuel delivery.

Do you need to tune for ITBS?

For the most part, ITB’s aren’t like old carbs that need to be “retuned” like a lot of people claim or think. It’s simply a set of runners with a butterfly valve on each one, and a boss for fuel injectors. Once you sync each runner to one another, there isn’t much to fall “out of tune”.

Which is better MAF or map?

Actual air flow (MAF) is more accurate than calculated air flow. Some cars have both MAP and MAF and use the MAP to fall back on if the MAF fails.

Is MAF or speed density better?

Speed density offers an advantage in that it is better at handling high-revving engines than a MAF sensor is. Speed density is still preferred by many modified car enthusiasts, because tuning is simplified and because the wire within a MAF sensor can become an obstruction at very high power-levels.

Does ITBS use more fuel?

ITB’s tend to improve how much air a motor can “process”, more air means more fuel, which means poor economy. But, as they also improve power, there is the possibility that economy can improve, IF the driver can control their right foot.

Is a larger throttle body worth it?

A larger throttle body delivers air at a higher rate than a stock engine, allowing the driver to feel an accelerating response from the vehicle sooner. In addition to increasing acceleration performance, larger throttle bodies can also boost overall horsepower.

What is an alpha-N system?

This is where the Alpha-N name derives from. Alpha for the angle of the throttle plates and N for RPM. Now if you have an Alpha-N system, and add a hotter set of cams that allow more air into the engine, but you do not reprogram…

Do you know what alpha-N sensor is?

You should at least know what it is because it is often used as a “sanity check” for primary control strategies. Alpha-N is also sometimes called “TPS maps” because the only sensor that is used for determination of fueling is the Throttle Position Sensor.

Is the alpha-N worth it?

Alpha-N is very poor at dealing with hills (think about engine load going up and down hills at a constant throttle position), temperature variations and just about anything else that you’d care about except close to wide open throttle where it does fine.

Is alpha-N a good measure of engine mass?

It’s not perfect, but it works ok most of the time for changes that are not too drastically different than the baseline. Alpha-N is different. Here there is no direct measurement of either the mass of air, nor the volume of air entering the engine.