Quote:
Originally Posted by Sternjaeger
Thor, I used the 50/50 expression cos you mentioned "half and half", sorry, nothing really technical there
I have a fair experience with aviation piston engines (I was lucky enough to fiddle with 2 strokes and 4 strokes Rotax, Gypsy Major, Continental, Lycoming, P&W Wasp and lately I started to get acquainted with the RR Packard Merlin), but I am no engineer or techie, I am just a flier who's interested in knowing what's happening under the bonnet in front of his nose..
I am not entering in the merits of lambdas or mixture ratios because they're peculiar to the engines and aeroplanes (and as you said 100 posts wouldn't be enough), all I can tell you though is that yes, in theory a direct injected engine like the DB could be more "mixture efficient", although carb engines are handled according to strict parameters, so you would hardly notice any difference in the flames colouring.. if Oleg managed to implement a flame colour changing according to mixture values then this would be a boomer, cos we'd be able to adjust our mixtures by looking at the exhausts and might also be able do diagnose engine problems (i.e. red exhaust flames and sparks coming out would mean a bad, bad day.. or in case of radial engines, where the exhausts are normally connected via a ring exhaust, an intermittent flame from the main exhaust would mean misfiring cylinders etc..).
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First I would like to say how much I envy you for the described experience. I am much more into theory, calculations and various physic laws related to engines. Unfortunately I have very little time with real engines. I did say 'probably' more variable, so this means that someone who is also an engineer and has the experience should have to come here and verify this in practice.
I am though, more inclined to believe that this difference in flames is almost invisible or not noticeable when comparing them with fuel injected engines of the same era.
Quote:
Originally Posted by Sternjaeger
Come on Oleg, this is quality material we're delivering you here! 
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Agreed.

I see that Oleg has posted while I was writing my reply. Very nice.
Quote:
Originally Posted by W32Blaster
My Statemant was you can´t say it that Easy: 'Fuel Injection is working better than a carburator in terms of providing the RIGHT mixture for all operating conditions. '
Not which Technologie is best used to gain the goal of ideal mixture under all operating conditions!
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Alright. It may not be that easy to claim that (especially when comparing mechanical fuel injection with carburetors), there are advantages and disadvantages of both - but from technical perspective and engine development advancements (especially in todays road vehicles) direct fuel injection is light years ahead.
Quote:
Originally Posted by W32Blaster
Let´s say youll have a Pierburg 4A1 Carburator with ECU for fully closed loop control of a 3-Way Katalyst System and you compare it with a early k-Jet-Tronic, guess which one is more sophisticated in terms of providing right mixture for all operational state.
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The K-Jetronic lacks proper feedback to adjust the mixture because it doesn't have a lambda loop or lambda control. The biggest advantage of 3-Way Catalyst System (lambda control) is that engine can adjust to different types of fuel more or less automatically. It does not fix the main flaw of carburetors - inability to provide ideal mixture on all operational states.
However, mechanical injection could do only so much. Before ECU & lambda control were implemented.
Direct fuel injection coupled with specialized piston and cylinder head shapes to further improve fuel oxidation (burning) by creating swirls and tumbles (idling at low RPM even with high lambda values, up to 3.0) - is a light years ahead from any carburetor...