Brow'ing Down

[Bruce]

> Oscilloscope. It shows on my LED bar graph, but it's easier to pick out
> on a scope trace. I can get rid of most of it with additional filtering
> capacitance in the circuit, so it isn't much of a worry.
> > Also, what state of tune is the car your looking at?.
> > Race gas?.
> > I'm working on some theories about gas, and any comments about it
> > are welcome, in ref to WBs.
> No, just high oct unleaded for now. Recently converted engine from carb
> to efi. Same effect noticed in carb, before converted, which was one
> purpose for having two sensors. What I mean is, in Heywood and other
> books, they talk about the cyl-to-cyl variations in combustion *and also*
> firing-to-firing in each cyl . So I was hoping with the collector sensor
> to also see the greater fueling variations due to the carb & wet
> induction vrs. the improved port injection setup. You know, different
> jugs seeing diff AFR. So I spent a lot of time the last month looking at
> the AFR signal with the carb before conversion to efi. You can certainly
> see the differences, but I'm also real sure someone could write a big
> book on interpretation of afr signals. I notice that the highend Bosch
> meters have a dial-in filtering capability, so you can choose just how
> much filtering you want to do before you datalog. I might try doing this
> with a bunch of filter caps and a rotary switch.
> I would like to get to the point where I can be confident I'm seeing the
> combustion variations and not just some artifact in the signal. BTW I
> moved my injectors around to see if I could get any variation from them,
> but they are matched pretty good. You *can* pick out the cylinder clear
> as day, if you try swapping out a 24# inj for a 19# on one cyl (don't try
> this under load, of course), if you trigger your scope on cyl #1 ignition
> so the trace gets synced up properly. I did these tests at 2500rpm. I
> resorted to using the scope instead of the logger, to make sure I wasn't
> getting the noise from the logger itself, since it is also new. Next
> thing I would like to try is a sensor per cyl, close by each exh port.
> Maybe the 'noise' I'm seeing is an effect of the collector. Good thing
> this is a 4-banger, otherwise I would need a second mortgage for all
> these sensors. :)

Ahhh, 4 cyl., about 15 secs between cylinder firings at idle <g>.
Lots of time for reversion, in the exhaust, and all sorts of lil things.  By
which I mean when the sensor sees an exhuast pulse go by, there is a *slug*
of *high* pressure.  As it goes further down the pipe, the pressure (slight)
drops, and the exhaust can momentarrily almost stop,  At the other end of
the tubes, we have various other events going on, one exhuast valve closed
one opening, and one open (**in general**)  so at any given moment in time
there are lots of waves, pressures, flows in the pipe.  And we need to
mention here, that at overlap intially the exhaust flow vaporizes a bunch of
fuel and then as the exhaist valve close, some of that fresh stuff is drawn
into the pipe.   With enough resolution you can see all kinds of stuff going
on.   At one of the POWWOWs it became how clear this all was.   With a NTK
WB the display hardly flickered, but on a scope trace, you saw everything,
and I think I know what you mean about noise.  The sensor IMO can't respond
to none events, so there just is more going on then what it might seem like.

> Thanks again to the whole diy-WB team for such a great tool; we having
> fun now! I am looking forward to more people sharing their results and
> learning more about how to use it, and what more to learn about engines
> and tuning from it.

> [now, about the brow-beating :o]
> > So it really wasn't a compliment?.
> > Trouble with this international stuff, things can get lost in the
> > translation.  You'd have thought this being a USA list of origin,
> > subers
> > from other countries would at least try to present info., in a way,
> > that
> > partipants would understand.   And here I thought it had something
> > to do
> > with his site being copyrighted, and his disreguard for the WB
> > Users
> > agreement.   So your saying that he doesn't like to have such
> > matters
> > pointed out?
>
> Dang, no Bruce, it wasn't really a compliment, unless you are using
> high-brow-talk.

So he was trying to insult me?.   Geesh, and here I thought things were all
better...

>Then the best insults are the ones you can't be called
> on. :)

So he insults me for his actions?.  Gads, that doesn't make any sense.

>  Yes, it had something to do with you calling him on the hypocrisy
> of copyright notice on his own site, while him intentionally breaching
> the WB EULA. Good one. High-brows hate to be found out and especially
> called on their hyprocrisy. It's an assault against their main moral
> crutch: denial. Notice the General responding to my ridicule by
> pretending to take it as a joke. More denial. Perfectly consistent with
> his MO.

So this might just be a mental problem?.
Whew, at least it's nothing serious.   I'd bet with some professional help,
and work there is a cure.

> He's too far away to be soundly trounced, so I guess we'll just have to
> settle for ridicule.

Ridicule:
Words or actions intended to evoke contemptuous laughter at or feelings
toward a person or thing: "I know that ridicule may be a shield, but it is
not a weapon" (Dorothy Parker).

Tween this an learning the meaning of petulant the other day, the internet
is educational.
Bruce

> BLM


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