Projection

[Tyson McPherson]

Hello all,

Yes, you can use the D or DI systems without the O2 sensor. Unpluging the O2
simply puts the system in open loop mode.

Also, I will state again: the 502-20 digital two barrel system is idenitcal
to the orginal 2bbl Pro-Jection system, with the exception that it is now
digital and not analog. All adjustments are still made the same way, and it
does not use a Map sensor or IAC.

I have been on this list since last December. Most of what takes place here
is above my level of knowledge, but I do find it very interesting. I
subscribed to this list to learn more about EFI, and what is being done by
people like yourself. I am an outside sale person for Holley Performance
Products (northern California), and this has kept my experice limited to
Pro-Jection only. If there is anything I can to help just let me know.

Tyson
tyson at ns.net
www.holley.com


-----Original Message-----
From: Mike Jones <rmjones at cyberhighway.net>
To: 'diy_efi at efi332.eng.ohio-state.edu' <diy_efi at efi332.eng.ohio-state.edu>
Date: Thursday, April 02, 1998 8:26 AM
Subject: RE: Projection


>Andy,
>
>Can the 4Di be used without the O2 sensor?  (I realize tuning becomes more
>critical.)  Due to water-cooled exhaust system my marine application makes
>implementation of an O2 sensor difficult.  (One possibility I thought of is
>to tap into the currently blanked-off EGR port and run a seperate mini
>exhaust, but this raises questions of its own, such as how much flow would
>be required to give accurate feedback, where to discharge this exhaust,
>etc.  So for now no O2 sensor is my goal.)
>
>Holley is advertising a marine 4Di which should go on sale in a couple of
>months.  I've spoke with Holley tech twice.  One rep said that the marine
>4Di must use the O2 sensor and the other one said that it wasn't necessary.
> Sadly typical for Holley.
>
>Thanks,
>
>Mike Jones
>
>>>Squash  wrote:
>
>I have 2 4Di manuals.  One is not released yet (i feel so special...).
>If you would like a copy of that an the software, gimme a jingle.  The
>4Di uses a heated O2 sensor, by the way.  I drive mine to work and all
>over the place all the time, so i know it works!
>
>Andy Quaas>>
>
>
>