I've seen and heard of people blowing thru the AFM - placing it after the turbo/intercooler.

Some have said it increases performance (somehow), but I didn't get an explanation.

What does it do? And, how effective is it, really:scratch: ?

Enlighten me, o' Rotary Gurus...



nvr2muchboost

Its basically a ghetto rig. It works......but not for long, will do more damage than good. Waste of time IMO.

That's a bold claim, can you back that up?

Yes, Ive seen quite a few guys do it. Then see those same guys rebuilding motors.

The AFM has a temp sensor which, due to the increased temp in boosted air and also due to the pressure difference does NOT read accurately. Also, the afm is calibrated to move a certain amount under near-atmospheric pressure, not under higher density (albeit slower moving at this point) air which changes its relative calibration as well. Neither of these would be seen as a positive thing on a stock system. And if your system isn't stock to the point where you'd consider something like this for whatever reason, you should be seriously considering aftermarket and losing the AFM all together anyway. That's my opinion.

Thnx for giving the technical version to what i said. I was just lazy and didn't want to type all that out..... https://www.nopistons.com/forums/pub...#>/biggrin.png

...and the barometric pressure sensor is missing from the equation too at that point - not that it would read boost very well anyway. (On the S4 anyway baro is part of the mass air calc - don't know about S5)