I have been rescaling my MAF and noticed the MAF Hz formula didn't correctly convert from display back to ROM, Not sure if this has been changed in later xmls, but here it is for your interest.

<scaling name="MAFHz" units="Hz" toexpr="6.29*x/64" frexpr="x*64/6.29" format="%.0f" min="0" max="5000" inc="1" storagetype="int16" endian="big"/>

 

Hmm, nice catch. I will have to see what my current scaling values are now.

-Jamie
(jack_of_trades)

 

It will read the same, but my previous xmls didn't write back correctly. The above fixes that.

 

Just for preservation sake, I will add the correction here. The formula you posted was the original WRONG one, not the revised one. Here is the corrected one:

<scaling name="MAFHz" units="Hz" toexpr="6.29*x/64" frexpr="x*64/6.29" format="%.0f" min="0" max="5000" inc="1" storagetype="int16" endian="big"/>

-Jamie

 

So it was Jamie, sorry about that. First post corrected with corrected formula,

 

This should be corrected in tephra defs. From what I know, at least 9417 SD 2.0 has the wrong formula.
without the right forumula , it's impossible to edit MAF compensation Y axis (MAFHZ)

 

Actually the correct eval is x*64/6.25

6.29 will give 1610Hz, but it should be 1600Hz, so 6.25.

A minor detail but if you want to be accurate....

 

What effect will this have on MAF Compensation if I re-flash my existing tune after changing the scaling to the correct definition?

 

nil effect, it is just to present the data accurately.

 

Cheers Merlin. I was thinking it might impact Maf Comp because the Hertz values I adjusted Comp at changed once I corrected the scaling. Thanks for correcting my misunderstanding.