a MAF too small

[Ludis Langens]

Dave Zug wrote:
> 
> I have an 89 5.7l Iroc, 165 ECM, ARAP (vette) binary. I have put a
> supercharger on it and the computer has no idea what airflow is
> coming in after about 3000 rpm cause the MAF reads 255 right about
> there.
> 
> If I drill holes PAST the maf sensor, effectively forcing it to
> read 75% of the actual air entering the engine.. I can alter the MAF
> tables to re-compensate.
> 
> Am I missing an easier solution? Do I even really care what's going
> on at WOT above 3000 rpm?  I MAY max the MAF at 70% TPS and 3500 rpm
> so my thinking is I DO care.

Isn't the problem not that your maxing the MAF sensor, but that you are
maxing the computers internal airflow variable at 255 g/s?  It's a
frequency MAF, right?

It seems to me that the solution is to change the MAF variable to read
in units of 2 g/s.  You'll need to change the MAF frequency->flow
tables, and all references to the MAF variable(s).  No need to change
any hardware unless you decide that the original MAF is constricting the airflow.

The stock MAF sensor should be able to measure more than 255 g/s.  The
output frequency will simply go beyond the normal range.  It might go
non-linear, and/or the ECM's frequency measurement may have lots of
error, but it should be a usable measurement.

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/