Still more Questions ....

[Clinton L. Corbin]

>I have more question on MAF sensors
>
>The MAF on OEM's is always placed very fare from the throtle body by doing 
>this we have to realiase that we have the intake + the air hose that act as 
>a resevoir after the metered air has passed the MAF, would it not be better 
>placed as close as posible to the intake ??? And also why not just put it 
>after the T-Body and calculate the real air density, since usually we have 
>coulant heating the the T-Body.

One of the Mustang magagazines did a bit of hopping up on a 95 Mustang GT.
They added a Paxten type supercharger (exactly like a Turbo on the compressor
side, only driven from the crankshaft instead of the exhaust).  After the
hop-up, the car had a very rough idle and just didn't run as smoothly as 
it did before.  They played with the fuel pressure (to richen the mixture),
but nothing really helped.  Until they moved the MAF sensor back to were it
originally was (about 30cm infront of the throttle body).  With the kit 
they had used, the MAF was placed infront of the supercharger.  This was 
almost two meters (about six feet for the U.S.A.!) from the throttle body.
After they changed it back, the motor ran great (and made serious HP due
to the blower!).

>And just to screw things around on super/turbo charged engins the T-Body is 
>after the compressor by placing it there we have to add a bypass valve on 
>the intaketo reduce the chance of over boost when the trotle plates close 
>sudenly.  By putting the T-Body beafore the compressor we do not nead the 
>bypass valve but the compressor must have sealedbearing shafts to keep from 
>sucking the oil from them when the intake is at a vacum, Would there be any 
>other ploblems ????
>
>//--------------------------------------------------------------------------
>// Marchil at IBM.NET
>// Alain Marchildon
>// 1271 Bernard West
>// Outremont, Quebec Canada
>// H2V 1V8

Basically, a little bit of air storage after the MAF doesn't hurt drivablitly.
A lot does.  Due to resonant frequencies, it would also appear that a small
diameter, but long, tube would be worse that a large diameter, but short, one.
The reason being the resonant frequencies of the long, thin tube being lower
than for the short, large diameter tube.  Need more experimentation on this.

Clint
ccorbin at intel7.intel.com