Ambient Pressure on compressor.

[John Dammeyer]

Hi Walt,

Why?  I can see the need for the ambient pressure to use in conjunction with
the MAP sensor to determine, in effect,  the pressure differential which
creates the force to move the air into the cylinders.

Depending on the RPM of the blower, the waste gate and the boost created,
the ambient pressure means almost nothing doesn't it?  How would you use it
in a formula to calculate fuel mixture?

John


----- Original Message -----
From: "Walter Sherwin" <wsherwin at home.com>
To: <diy_efi at diy-efi.org>
Sent: Thursday, December 07, 2000 7:53 PM
Subject: Re: Do I need an Air Flow Meter?


> The BARO sensor function should still be setup to comprehend the ambient
> conditions an the entrance of the compressor.  More so for a positive
> displacement compressor (roots or screw) than a centrifugal or turbo, but,
> still important in terms of any upstream inlet restrictions.....
>
> Walt.
>
>
> >
> > Brings up an interesting question.  For a Turbo'd engine using a MAP
> sensor
> > obviously the need for the Barometer goes away if the engine is always
> under
> > a slight amount of boost.  Perhaps the barometer sensor needs to be
> > connected to the front of the throttle plate.  Perhaps that's why SAAB
> went
> > to a hot wire mass air flow sensor instead.
> >
>
>
> --------------------------------------------------------------------------
--
> To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the
quotes)
> in the body of a message (not the subject) to majordomo at lists.diy-efi.org
>
>
>

----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org