What he was doing was using the stock O2 to determine individual cylinder
info - within the range of the sensor. Notice the correlation on his graphs between
stock O2 volts and wideband A/F ratio - very little if any. I am not saying stock
O2's are junk, they are very good at what they do, but that "do" is centereed around
stoich. At WOT you will want closer to 13:1, and they will be useless there.
The individual cylinder tuning *is*interesting though
http://shared.slowcar.net/1999-01-0546.pdf
is a SAE paper from Delphi documenting use of a standard switching type O2 to
interpret individual cylinder information.
Chris
----- Original Message -----
From: "Shane Moseley" <smoseley@ix.netcom.com>
To: <dakota-truck@buffnet.net>
Sent: Thursday, July 12, 2001 1:42 PM
Subject: DML: Re: Intellitronix A/F meter
| I used to think that way also. Now....I'm not so sure. Check out the following link:
|
| http://www.dickselectronics.cjb.net/
|
| That would be cool if you could just do some processing of the existing O2 sensors signal
| and end up with an approximation of the A/F of each cylinder. I have a data acquisition
| board that can read four channels of analog +-10V signals. It can sample at 240 samples
| per second. Not sure what the input impedence is tho - wondering if I can do some
| processing of my own to see what shows up on our signal.
|
| Thoughts?
|
| Latr,
|
| Shane
|
| chris@slowcar.net wrote:
|
| > Maybe I missed out on part of the discussion (sorry) but the reason
| > for the bouncing is because the truck is operating in Closed loop and you
| > are close to 14.7:1 where the O2 transfer function is VERY steep so even
| > the exhaust pulses will cause "bouncing"
| >
| > If you are trying to determine anything tuning wise from stock O2's you
| > should just give up. :) Seriously, take a look at this document I just put
| > up - it gives a good explanation with graphs as to why this will not work well.
| >
| > http://shared.slowcar.net/o2_volts.xls
| >
| > If you want any meaningful info you need to switch to a wideband. You
| > *could* possibly use the Bosch LSM-11 sensor instead, which is basically
| > a refined and hand picked stock type sensor (only one nernst pump, normal
| > wideband is pretty much 2 - one actually controls permeability). This would
| > work with a standard style meter, though a digital readout would be the only
| > way to do it justice. Pricey though. The other option is a NTK style
| > 5 wire wideband, which is what horiba, etc. use - but you need to a controller
| > circuit for one of these, there are a couple of diy-efi projects out for this circuit
| > on their homepage. (diy-efi)
| >
| > Chris Bennight
| > http://www.slowcar.net
| > 66 Charger for sale
| > http://charger.slowcar.net
| >
| > ----- Original Message -----
| > From: "John Neff" <jndneff@texas.net>
| > To: "Dakota Mailing List" <dakota-truck@buffnet.net>
| > Sent: Tuesday, July 10, 2001 11:10 PM
| > Subject: DML: Re: Intellitronix A/F meter
| >
| > | Right, but if this is a good gauge, I can do it without the added expense of
| > | another O2 sensor and the labor to install the bung. Plus, it's an analog
| > | gauge which I would prefer since everything else in the truck is analog. I'm
| > | just curious if anyone has used Intellitronx gauges and if so, was it a good
| > | buy for them?
| > |
| > | John
| > |
| > | >You can do it (no bouncing) with an extra O2 sensor.
| > |
| > |
| > |
| > |
| > |
|
| --
| '96 IndyRam-HisIndy-MPI TB Pulleys RTcam MPComp HVoilpump DynaGearDoubleRoller
| WindageTray CompTAs
| '96 IndyRam-HerIndy-numbered(#142)"Track Truck"
| '74 Triple-Black Dodge Challenger Rallye 360 EFI R&D vehicle
| '93 Dakota CC 318 - soon to be mine 8)
|
|
|
|
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