a MAF too small

[Ludis Langens]

Dave Zug wrote:
> 
> OK right there is the question:  "AND ALL REFERENCES TO MAF
> VARIABLES"  I understand things such as comparisons (trip points)
> etc... but how to determine what they are... ?  I could start with
> G/S and trace thru the code and find everything it touches (looong
> time) and then half each one of them.. then I'd have to HALF each
> comparison to each variable that was CALCULATED using the original...
> unless of coarse the usage was in a formula where the MAF value was
> MULTIPLIED. or DIVIDED. then what the heck can you do.  Am I
> over-complicating things?

You could do what GM does in the 2-bar MAP programs - have two sets of
variables, one for the original range, and one for the increased range. 
Most of the code can get by with the original values - stuff like trip
points, idle control, closed loop control, and most error codes.  In the
2-bar MAP systems, only the timing advance, fuel calculation, and some
boost related logic needs the 2-bar values.

If the MAF value gets multiplied or divided, your scale factor transfers
through to the product or quotient.  Just some simple algebra.  If you
have a product, it might be retained as a 16 bit value.  This should
give enough range for you to apply the scale factor right then - and not
have to worry about it in further calculations.

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