DIY_EFI Digest V4 #696

[Tom Parker]

Bobby Radomirov <supra90t at prodigy.net> wrote:

>The O2 sensor varies the voltage constantly. Abouth 8 times per sec on a
>good one and 4 times per sec one old one.

It is my understanding that the computer varies the mixture, which the
sensor detects and responds by varying the output voltage. This is quite
different from the sensor varing the voltage on it's own!!!

>The perfect 14.7-1 mixture is
>about .480V anything that is under is Lean anything over is Rich.

"Perfect", "Lean" and "Rich" are open to interpretation.

>The
>Max power range is abouth 10:1 - 12:1 mixture. You can cheat on the O2
>sensor my puting small resistor in series with the circuit you will have
>some initial voltage drop accross it and will cause the Computer to
>richen the mixture. Althou I dont see why you would do that Because at
>WOT teh computer doesnt receive input from the O2 sensor and it will run
>at teh best preprogramed mixture for teh particular engine.

When you change teh engine, the preprogramed computer will no longer provide
the "best" mixture for the engine. Also your idea of "best" may differ from
that of the manufacturer.

>The point is
>in making other sensors like temp sensor, air temp sensor, AFM to read
>denser air and colder temperatures. That added the resistor accross the
>O2 wire will richen the mixture. But it might afect performance as well.
>Richer mixture doesnt neseseraly means that you will have more HP or
>Torgue. It all depends on the engine design

It also depends on the design of the ECU and the program it is running.

>DIY_EFI Digest wrote:
>>
>> DIY_EFI Digest      Wednesday, December 15 1999      Volume 04 : Number 696


PLEASE DO NOT QUOTE THE WHOLE DIGEST! Doing so can crash the server, apart
from wasting everyone's time.


--
Tom Parker - parkert at ihug.co.nz
           - http://www.geocities.com/MotorCity/Track/8381/