MAF Conversions

[RABBITT_Andrew at mv8.orbeng.com.au]

From: (peter paul fenske) pfenske at direct.ca:smtp
Date:  3/06/96 19:49

>1- what does a MAF sensor offer that a MAP and inlet air temp sensor 
>
>>MAF directly measures Air Mass. Fueling is simply based on AF ratio
>>desired not extensive engine mapping. In other words a change in
>>engine parms does not require a recalibration within limits.

But you can calculate Mass Airflow from manifold temp, air density and 
engine speed.  Why is this so inferior?

>
>>MAF is continuous. Just like MAT or CTC.
>
What do you mean by continuous?  Most ECU's are digital and require 
some form of ADC, therefore you have to decide where (time-wise) to 
sample the sensor output.

>6 - what kind of manifold filling compensation do people use?
>
>>Usually taken care of in VE corrector.
>
VE? Volumetric Efficiency?  What sort of corrector/algorithm?

re: airflow fluctuations, I've data from a 1.8l 4-cyl that I'm working 
on that at one speed-load point has airflow varying from 20g/s to 
70g/s at twice crank speed!  This would not be uncommon.  How have 
people overcome this in MAF conversions?