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Does an Apexi Air Flow Controller do anything about the stock AFM max out point?

It looks to me like the SAFC stops making any adjustments when the AFM maxes out. I have noticed on my car that when you recall the peak figures on the SAFC it says that the correction is 0% when the AFM voltage shows 100%, even though it is set to make corrections to the AFM signal from 2000 - 7000 rpm.

Of course I haven't been able to watch it in real time at 5000rpm+ on the road :)

There is not a black and white answer to this question. Just because the AFM reaches 5.1 volts output doesn't always mean it has to be changed

The only time you really need an AFM upgrade is when unanticipateable changes in airflow occur, ie; not linear with rpm changes. At high rpm (ie; past boost build and camshaft timing effects) this shouldn't be an issue. The fuel and ignition requirements are satisfactorily driven off the rpm change.

Keeping the above in mind, I have seen an RB30 run quite happily on an RB20 AFM at 265 rwkw. I have also had to change an RB25 AFM at 225 rwkw because the airflow changes where unpredicable (ie; not linear with rpm).

:) cheers :D

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