AFM on cooler piping

[GTStR32]

Why do people put there AFM on the cooler piping. I know people do it on there VL turbo's, is there any performance gains.

I have been told to do it to my car ?

I wanna know why people do it

[meggala]

I wouldn't do it there are better way to spend your money and get some power. did you get your car sorted yet.

meggala

[Bo0sT_JuNkY]

dont no about power gains,But I did it on my vl for the noise u no the po poo pooo that vl's make.But i blew my afm after a month or so ,Wouldnt like wrecking a r33 one as it cost triple the amount a vl does.

[blind_elk]

Good question.

The AFM relies on the air coming into the engine to cool a heated wire. The air in the IC piping is, in general, going to be HOTTER than the air coming into the Air Box / Pod. If the air is hotter, it won't cool the AFM sensor as much. Therefore the ECU thinks there is LESS air than there really is. So, it reduces the fuel.

ping, ping, ping. BANG!

Is this the right reasoning as to why Mr Nissan didn't mount the AFM in the IC piping?

[Warpspeed]

Actually the hot wire flowmeters have two heated wires. One is in still air, and the other in the moving airstream. Airflow is the difference in temperature between the two wires. That way ambient temperature changes cancel out.

But I think you are right. Placing the flowmeter after the turbo will give sudden extreme spikes in temperature that would probably cause large short term errors in reading the airflow.

A flap type flowmeter might be better, but high boost pressure may burst it !

[turbomad]

Apparently JPC in Melb recommend this mod to supply more power, it generally goes after the IC. They say there've never had one break either, AFM wires are very strong.

[Cubes]

If the AFM was directly in front of the Throttle Body wouldn't it provide more accurate fueling.

i.e on and off throttle, bov etc?!?!?!?