MAF vs MAP

[Chris Conlon]

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Dr. Bruce wrote:

> > Other than the reduced flow restriction of a MAP over a MAF are there
> > other advantages??
>
> MAF has the "disadvantage" of having the delay of the hot wire
> to change temperature.
> MAP can be slight more accurate during transistions, because of the above.
> ...
> Either of the following can be true
>   A properly tuned MAF is better than a poorly tuned MAP
>   A properly tuned MAP is better than a poorly tuned MAF

I agree with this, especially with the last part. My additional few cents:

MAP sensors can have very fast response times, this can be a good thing
but only if you have your filtering in order, which may be tricky.

MAP sensors may have better dynamic range (again, if the filtering is
right), but may *need* better dynamic range and finer map resolution.
For instance if you want a wild-cam MAP'ed engine to idle well, your
map had better provide fine resolution at low vaccum and low RPMs.
My *guess* is a MAP'ed engine could run better than a MAF engine
on the low end *and* on the high end, but *only* if the A/F map has
enough resolution in all the right places. (I don't think most do.)
Otherwise the simplicity of measuring the mass flow more or less
directly will win out; a much coarser map can be used and you'll still
get decent results.

My $0.02, apply salt before consuming.

   Chris C.

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