O2 / Lambda Sensor Data

[Bruce Plecan]

From: "Will Reeve" <will at oxfordcryosystems.co.uk>
Subject: RE: O2 / Lambda Sensor Data
> >> I come from an applied physics upbringing and I know 2 cars is not
> ideal,
> >> but it's better than 1!
> >I fail to see where that is an excuse for giving out poor info..

> Poor info? I was reporting my experimental results. I outlined the
> experiment, and reported the results, these results are repeatable, and
> have been independently verified with a completely different set of
> components. I don't (and didn't) state that the readings are absolute,
> however with a accurate calibrated mixture meter stuck into the exhaust
> I think the unit could be calibrate to report more precise ratios. From
> my experience a lambda sensor and meter combination CAN and DOES measure
> an increase or decrease in WOT injector duration on these vehicles.

Have you read the archives, and studied the matter?.
If you investigate further, you'll see where your limited observations fall
apart.

> >> As long as you keep the sensor roughly at the same
> >> temperature for DIY use I think it's fine, it may not be absolute but
> it
> can
> >> measure the presence of more of less fuel, even off stoichiometric. I
> hope
> >> to get a thermocouple in there soon to monitor the temperature.
> >
> >Might read further and see that backpressure can also play a role.
> >Also, not all sensors switch over at .5v.

> Obviously need to get one whose response matches the curve programmed
> into the meter, which is the Bosch zirconium dioxide example.

And, let me repeat again, not all switch over at .5v.
To include some of the Bosch zirconium.

> >> I wouldn't know how to read the plugs accurately and the only trouble
> is
> you
> >> can't read the plugs while they are still in the engine :-) One
> advantage
> I
> >> didn't mention is that the WOT map curve isn't perfectly flat. I
> guess it
> >> takes into account the volume efficiency of the engine. The standard
> curve
> >> shape gave a wobbly mixture across the range(read from the mixture
> meter),
> >> we re-shaped the curve to give a constant mixture reading throughout
> the
> rev
> >> range.
> >>
> >> I'll be the first to admit I don't know the ins and outs of engine
> tuning.
> >>
> >>And you want to give advise?.
>
> Reading back through my posts I don't think I was advising at all, just
> reporting what I did, and interpreted my results. People can do with
> them what they want. I thought I might be helping the original poster a
> bit, that's all.

To state that x-y-x works, is stating something as fact.
He wanted to build a *short cut* for looking at AFRs, and could easy assume
that he was safe in what he was doing based on what you stated as fact.
You want to quantee what you say?,  for any engines mistuned using your
info?.

> >> I'm just a evening hobbyist, but the car feels better now, and
> hopefully
> >> will give a few more ponies at the rolling road (at 60quid a throw I
> can't
> >> afford to tune it on the rolling road itself, and besides it fun to
> have a
> >> go yourself)
> >
> >And remember, Buttometer readings are meaningless.
> >
>
> P.S. Can we take this argument to personal email? I don't think the list
> is the place for it :-)

No this is not personal.
You want to state things, as fact based on some limited testing.   That is
misleading,    and needs to be publiclly disputed
Bruce
>
> Will
> will at reeve.org.uk
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