[Diy_efi] Air/Fuel meter now working! And L-jetronic

[Amd CPU]

OK, i'm not answering all this but...
I've read some ignition researches, where they saw that every ignition event
needs its own timing they can be 5deg or more off on worst case. So the best
ignition timing will be the timing with least deviation. And that what is
giving us out 100% of efficiency. In hitech solutions we could reduce
average error of timing from 2.5 to 1deg. So we could win another 2% of
efficiency, if we build engine for 2M miles.

I haven't heard the same situation in fueling, but there it deviates from
ideal.
I believe we can call our engines pretty fast even when using our year 2000
technology.
And this 2% is again lost on fine-tuned-AFR engine.

Now on computer-age, when our ignition-systems act fast, valve timing is
still slow. Every cylinder every cycle needs its own control.

"Just my 10%" of efficiency & power from ideally tuned engine.
On regular engine we could talk about 20% wasting.

----- Original Message ----- 
From: "Adam Wade" <espresso_doppio at yahoo.com>
To: <diy_efi at diy-efi.org>
Sent: Friday, June 17, 2005 6:03 AM
Subject: Re: [Diy_efi] Air/Fuel meter now working! And L-jetronic


> --- Astrona <amdcpu at hot.ee> wrote:
>
> > If something is pushed back, it restricts also the
> > flow.
>
> But it is not subtracted from what was measured
> flowing through, and therefore the mixture will be
> over-rich on subsequent injector events under the same
> or similar conditions.
>
> > Most of todays systems doesn't measure these things.
>
> That's because most of today's systems already have
> the engine's behavior due to intake, cam, and exhaust
> design considerations knitted into the maps.  This is
> why you need to change maps if you change cam profile
> or timing, or modify the intake or exhaust so as to
> have a signficantly different behavior from stock.
> I'd have to argue that replacing the entire exhaust
> and intake systems with a turbo setup would qualify.
>
> >> How could you determine how much air was entering
> >> the cylinder if you're measuring air entering the
> >> plenum?  If air pressure in the plenum never
> >> changed, this MIGHT work, but if pressure in the
> >> plenum changes (especially if it changes quickly,
> >> which is common on turbo apps), it CAN'T work
> >> properly (unless you add a plenum air pressure
> >> reading somewhere, in which case why bother with a
> >> VAF?)
>
> > I agree, should just use MAP.
>
> So you've circled around.  You said the L-Jet system
> should be fine for this application, and now you're
> saying that it is insufficient, as I've been
> suggesting all along.
>
> > But in theory, if plenum pressure changes, it must
> > pump in air if plenum dimensions are not changing.
>
> But all that air does not necessarily enter the
> combustion chamber during the same cycle that it
> enters the plenum, does it?  If it did, plenum
> pressure would never change...  But it does, and
> often, in a turbo app.
>
> > Yeah, with turbos it is complicated, since they have
> > "blow-off" too.
>
> Why would that complicate anything, unless you were
> not measuring pressure in the plenum?
>
> > We need cylinder pressure sensor and direct
> > injection.
>
> Cylinder pressure sensing is done easily enough with
> piezoelectric washers under the spark plugs.  Works
> well enough for ignition timing that at least one
> company is developing an ignition controller using
> that as the only "timing" sensor.
>
> DI has some advantages, but is not terribly cheap to
> implement.  For best power use, I don't see much
> advantage unless you're worrying about fuel economy at
> the same time.
>
> > Havn't you looked inside l-jetronic, they have many
> > arrays of resistors.
>
> I've never seen an array of resistors inside any
> L-Jet.  Perhaps you can show me which ones correspond
> to particular load/speed points?
>
> I see some isolation resistors at the connectors here.
>  Where are the arrays of resistors that constitute a
> "map"?
>
> <http://www.jagweb.com/jagworld/42efi/ecu_large.jpg>
> <http://www.jagweb.com/jagworld/42efi/us_ecu_large.jpg>
>
> There's a great shot of an ECU interior in "Gasoline
> Fuel Injection System: L-Jetronic", from Bosch GmbH,
> which also shows no "arrays of resistors".  I can scan
> and host it if you'd like.
>
> > We can call map inside the EPROM also a "rough
> > approximation of a fueling curve". :)
>
> No, we can't, since the main 2D maps correspond
> directly to injector open times (although they may be
> scaled by other sensors).
>
> > OK, lets stop this :D
>
> Yay.  I was starting to think it might never end...
>
> | 82 Honda CX500 Turbo (Cassandra)  90 Kwak Zephyr 550 (Daphne) |
> | "It was like an emergency ward after a great catastrophe; it  |
> |   didn't matter what race or class the victims belonged to.   |
> |  They were all given the same miracle drug, which was coffee. |
> |   The catastrophe in this case, of course, was that the sun   |
> |     had come up again."                    -Kurt Vonnegut     |
> | M/C Fuel Inj. Hndbk. @ Amazon.com -  http://tinyurl.com/6o3ze |
>
>
>
> ____________________________________________________
> Yahoo! Sports
> Rekindle the Rivalries. Sign up for Fantasy Football
> http://football.fantasysports.yahoo.com
> _______________________________________________
> Diy_efi mailing list
> Diy_efi at diy-efi.org
> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>
>
> -- 
> No virus found in this incoming message.
> Checked by AVG Anti-Virus.
> Version: 7.0.323 / Virus Database: 267.7.3/15 - Release Date: 6/14/2005
>
>



-- 
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.323 / Virus Database: 267.7.3/15 - Release Date: 6/14/2005