afm vs. pressure sensor
 

I have a 91 n/a, when i originally wired my safcII, I wired it to the air flow meter connection.

I have subsequently installed a jspec turbo engine. Should I change the wiring over to the pressure sensor now? What are the advatages. I don't have a wideband, so I am planning on going and having it tuned by a pro.

The only major mod is 3" downpipe and exhaust, the rest is stock for now.

You still want the air flow in & out wire through the S-AFC.
That is still your primary tuning control.

The option is moving the THR input to the pressure sensor. (My preference)

Once you have tasted the "dark side" (boost) you never go back. :cool: .

The airflow signal is the only modified signal.

The advantage of using the boost/pressure sensor as the throttle input is that you can tune for boost. I believe with the standard TII pressure sensor, 0psi comes somewhere around 60%, regardless of the RPM. Throttle position, contrary to popular belief, doesn't mean crap. It just affects the manifold pressure, which is what actually controls the engine output.

Using the boost sensor takes care of the fact that at 2000 RPM, 1/3rd throttle may be all you need to reach full manifold pressure (on a NA), and the rest of it does nothing. Using the boost sensor, this will be tuned properly.

-=Russ=-

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