16bit MAF xfer function in '165

[NickG]

>Hi Nick:  What have to done to your engine to make it read 255 grams/sec at
>4000 rpms?  I have ported my maf and removed the heat sinks and it reads
255
>at about 4700 rpm's.  When the engine was stock it would never go over
about
>208 grams/sec period.  I now have a 355 cu in engine.

The engine in question is a 408 cu. in. small block with ported and extrude
honed heads, blah, blah, blah.........;) and also a ported MAF.

>I had to adjust the flow in the
>maf tables below 15 grams sec to get the bl back in line.
>I think if you just made the existing maf flow more and adjusted the spark
>and fuel to match up I just think you will lose some resolution.

I don't quite see why you say I'd lose some resolution?  I understand your
method above, but it doesn't lose resolution on the low end of the load/rpm
scale. What it does lose is measuring ability at the upper load/rpm points.
Is that what you mean?

If I use an MAF that can only measure up to 255gms/sec, and it saturates
early (like it does now at 4000rpm), then the chip will have to be 'fudged'
to get the proper fuel above that RPM point. The ECM will see that the
engine is using 255gms/sec at 4K rpm and at 5.5K rpm, when in reality, it'll
be using, say, 400gms/sec at 5.5K rpm.  The fuel tables will have to be set
with an ever increasing fuel mixture in order to keep making power.

But if I can make the ECM be able to read up to 512gms/sec, then the fuel
and spark tables will work just like they did when stock. The ECM will
detect the correct amount of air entering the engine, and hence, spray the
proper amount of fuel.

Nick


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