alpha-N equations?

[Greg Hermann]

>Just wondering about alpha-N injection systems (ones that meter fuel just
>from throttle position and RPM, without measuring either MAP or MAF).
>
>In general, air_volume = f(TPS, RPM).
>
>Is it necessary to keep a 3D map, or can it be reduced to a 2D lookup and a
>calculation to correct for the other parameter?
>
>I think that the relationship between TPS and air flow is likely to be
>highly non-linear, so the question reduces to whether at a constant
>throttle position, there is an easy relationship between RPM and air volume?
>
>How about if it is assumed that one knows the function VE(RPM) for the
>engine at WOT?
>
>Just playing with ideas.
>
>Mike

Based on a long ago memory of the shape of a mechanical alpha-N
cam,----it's pretty non-linear. Would hare to try to curve fit to the
shape!!

Regards, Greg