911S 2.7 different K-Jetronics

  • Yes, cobalt blue, that's how it is. I doubt whether you can speak of "modernizing" with all the additional stuff like the additional air slide.

    A lever with a cable is not as susceptible as all the extra stuff, so I might dismantle it......


    Greetings

    Benno

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  • Yes, cobalt blue, that's how it is. I doubt whether you can speak of "modernizing" with all the additional stuff like the additional air slide.

    A lever with a cable is not as susceptible as all the extra stuff, so I might dismantle it......


    Greetings

    Benno

    This drag lever doesn't even have a cable, it is simply connected to the throttle linkage. You simply use the lever to adjust the idle throttle speed during the engine warm-up phase.


    Personally, I really like the "rudimentary" technology of an early G-model, as troubleshooting is less complex and I was able to restore/repair the car myself with garage equipment.

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    Grüße aus Köln


    Bruno


    Porsche 911 S Targa 2.7 US von 1975 (orignal: Motor, Getriebe, SEV-Lima, und elektr. Motorraumgebläse), Blaupunkt Köln Stereo


    VW Golf 3 1800 CC 75 PS

    Käfer 1302 Cabrio 50 PS von 1972

    Landcruiser J7 von 1987 H

  • Dear people, I really don't know what's wrong with you.


    To disqualify the ZLS as an "add-on" and a (non-)modernization is, to put it mildly, audacious and completely incomprehensible to me.

    Of all things, the ZLS is the part of the K-jetronic that fails the least often. On the other hand, I think that the ZLS is a sensible and very pragmatic and good "electromechanical" solution for the early 1970s, when most cars still had carburetors, manual chokes and the like. For me, the hand throttle of the early K-Jetronic models was more of a makeshift solution, because the ZLS was probably not yet available or its use was still too expensive and the loss of comfort was still manageable. I don't know. But it doesn't matter.


    The fact is that the various versions of the K-Jetronic are a good example of how development has progressed. It's also clear that with each additional part, one more source of error comes into play, which can then cause the craziest symptoms. This can lead some people down the wrong path. But just because I don't understand a system or don't have the means to test it, it's impertinent to label it as inferior. If people thought like that everywhere, most people would still be sitting in trees and not in a 911...


    I really appreciate the level here in the forum, but if you read the last few posts in this thread, you might get the impression that there is more polemic than serious technical discussion.


    I don't want to start a fundamental discussion here, but - sorry - I just had to get this out. No offense intended. If you don't like my opinion, you can put me on "ignore".


    Thomas

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    81er ex-US 911 SC Coupé, platinmet., eSSD, K-Leder sw., Turboheckflügel & -frontspoiler, NSW, Maxilite 7/8J, Bilstein Fw("SpoStra" - noch...), 915/61, 930/16 o.Kat, WebCam 20/21 NW, hydr.KS, Dansk 92.502SD, 123 Ignition, orig. Porsche SWV, Seine Systems Gate Shift Kit, Momo Prototipo m.Nabenerhöhung


    „Nicht das Auto verdirbt den Charakter, aber wer keinen Charakter hat, sollte nicht Auto fahren.“

    Ferdinand Porsche

  • To disqualify the ZLS as an "add-on" and as (non-)modernization is, to put it mildly, audacious and completely incomprehensible to me.

    Of all things, the ZLS is the part of the K-jetronic that fails the least often. On the other hand, I think that the ZLS is a sensible and very pragmatic and good "electromechanical" solution for the early 1970s, when most cars still had carburetors, manual chokes and the like.

    To be honest, I don't know anyone around me who hasn't readjusted the ZLS.


    For me, the manual throttle of the early K-Jetronic models was more of a makeshift, because the ZLS was probably not yet available or its use was still too expensive and the loss of comfort was still manageable. I don't know. But it doesn't matter.

    This whole bimetal-based thing is predestined to become misaligned over the years. By the way, I've always really appreciated the "choke" on my 50s Beetles, as I've never had a problem with it in the last 30 years. The later Solex carburetors in the 60s and the ≥ 34 hp engines with cold start/automatic idle have all had problems over the decades.


    I really appreciate the level here in the forum, but if you read the last few posts in this thread, you might get the impression that there is more polemic than serious technical discussion.

    If you use this as a yardstick here, then every second thread with purchase recommendations would have to be closed :)

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    Alles über den 3.0 US SC Motor 930.16 und viel mehr unter:

    https://nineelevenheaven.wordpress.com/


    - 911 SC 3.0, USA Bj 82, unischwarz, SSIs, eigens entwickelte digitale Lambdaregelung sowie elektronische Kennfeld-gesteuerte Zündung
    - VW Oval-Käfer Export, Bj 1955, 30PS, Stratosilber
    - VW Brezel-Käfer, Bj 1950, 24,5 PS, Grau, orig. Philips Elomar Radio

  • Thomas,


    I liked your comment because I am very good at dealing with other opinions.


    I've spent the last few days studying all versions of the K-Jetronic very extensively and have also understood the various expansion stages, yes, I'm that bold.


    I come from the 356 and 944-968 corner and appreciate systems that work without additional things that break over the years and are expensive,


    So long and thanks for your input!!!!


    LG everyone


    Benno

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  • Early K-Jet, with that micro switch on the throttle -- and later ones -- have fun changing COMPLETELY ALL the fuel lines in ADDITION!


    And to think that both the 3.0L Carrera and the 3.0L Turbo have an ADDITIONAL hand throttle in addition to the auxiliary air valve....


    Lars

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    Nur wenn du schwarze Striche vom Kurvenausgang bis zum nächsten Bremspunkt ziehen kannst, hast du wirklich genug Leistung(Mark Donohue).


    Im Alter wird man immer knackiger -- da knackt es und da knackt es...


    Sechs 964er bisher mit abgerissenen Dilas --- 14(!!!) Ventilfederbrüche bei den letzten 5 Motoren! 4:3:3:1:3


    Porsche 911 -- der Volkssportwagen...


    "Hoffnung -- ist immer ein Mangel an Information!"


    Wer restauriert -- verliert...

  • Benno,


    I, too, am always happy to have an objective and professional exchange! k:gimmefive:

    And I also like to argue "with an open mind"... :kwink:


    Well, 356 is purely carburetor, 944&968 L-Jetronic or Motronic. The latter are more or less fully electronic/fully sequential systems, to which the K-Jetronic - regardless of the expansion stage - is hopelessly inferior. Absolutely clear.

    However, in my opinion, the comparison is also flawed at this point: what the electronics in the 944&968 do by means of the air slide/idle air regulator etc., the old K-Jetronic still has to do completely by hand. Apart from the clock valve of the Lambda-KA-Jetronic, there is no other electronically controlled actuator on the Americans. Everything else is mechanical or electromechanical.

    The Motronic idle speed actuator alone makes the ZLS, the start valve and the vacuum limiter of the KA-Jetronic completely superfluous. The WLR + thermal timer and cold start valve are replaced by the temperature sensor and longer injection times or injection quantities of the electronically controlled injection nozzles. Then there is not so much left to cause confusion.

    Naturally, a Motronic or L-Jetronic is always the far more reliable and superior system. However, it is not simpler, but the complexity is hidden in the software. At the same time, this makes it much more reliable and "stable", as is so often the case when fast and reliable electronics replace mechanics. And that's a good thing, no question. But I still believe that the K-jetronic was an excellent alternative to other systems in its day, which is why it was used almost universally by most car manufacturers. As is so often the case - the better is the enemy of the good.


    Greetings, Thomas

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    81er ex-US 911 SC Coupé, platinmet., eSSD, K-Leder sw., Turboheckflügel & -frontspoiler, NSW, Maxilite 7/8J, Bilstein Fw("SpoStra" - noch...), 915/61, 930/16 o.Kat, WebCam 20/21 NW, hydr.KS, Dansk 92.502SD, 123 Ignition, orig. Porsche SWV, Seine Systems Gate Shift Kit, Momo Prototipo m.Nabenerhöhung


    „Nicht das Auto verdirbt den Charakter, aber wer keinen Charakter hat, sollte nicht Auto fahren.“

    Ferdinand Porsche

    Edited once, last by Schulisco ().

  • L-Jetronic and Motronic. The latter are more or less fully electronic/fully sequential systems, to which the K-Jetronic - regardless of the expansion stage - is hopelessly inferior. Absolutely clear.

    Hello Thomas, the Motronic for the 3.2, for example, does not have fully sequential injection, it injects in groups, there is no other way, as it receives the signal via a sensor on the crankshaft/flywheel, and only 360° resolution exists here. I am not aware that the 3.2 Motronic has a camshaft sensor, nor that there is a position sensor in the distributor ... This means that it would not be possible to differentiate between cylinders 1 and 4 in the injection for the control unit, so it would only be possible in pairs (3x2), but even this is not done by the Motronic on the 3.2, instead it injects side by side (2x3), i.e. 1/2/3 and 4/5/6.

    If you look at the supply lines of the electronics on the Motronic, you can see that it injects 2x3 wise:

    https://forums.pelicanparts.co…3-2-911-618-111-13-a.html


    EDIT: A better circuit diagram of the 3.2, where you can also recognize it:

    https://ensaster.com/pics/peli…engine-wiring-diagram.pdf

    This post has been automatically translated.

    Alles über den 3.0 US SC Motor 930.16 und viel mehr unter:

    https://nineelevenheaven.wordpress.com/


    - 911 SC 3.0, USA Bj 82, unischwarz, SSIs, eigens entwickelte digitale Lambdaregelung sowie elektronische Kennfeld-gesteuerte Zündung
    - VW Oval-Käfer Export, Bj 1955, 30PS, Stratosilber
    - VW Brezel-Käfer, Bj 1950, 24,5 PS, Grau, orig. Philips Elomar Radio

    Edited once, last by AndrewCologne ().

  • Yes, I know that the Carrera doesn't have fully sequential fuel injection, thanks again for pointing that out. But it's not really relevant, because the way the fuel is metered (electronic injection) is quite different from the K.Jetronic. Nevertheless, they are all intake manifold injectors. Thanks again for the hint.

    This last circuit diagram of the 3.2 is great, I didn't know it yet.

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    81er ex-US 911 SC Coupé, platinmet., eSSD, K-Leder sw., Turboheckflügel & -frontspoiler, NSW, Maxilite 7/8J, Bilstein Fw("SpoStra" - noch...), 915/61, 930/16 o.Kat, WebCam 20/21 NW, hydr.KS, Dansk 92.502SD, 123 Ignition, orig. Porsche SWV, Seine Systems Gate Shift Kit, Momo Prototipo m.Nabenerhöhung


    „Nicht das Auto verdirbt den Charakter, aber wer keinen Charakter hat, sollte nicht Auto fahren.“

    Ferdinand Porsche

  • I really am the opposite of an Originalo.

    Even words like "factory delivery condition" and ONLY DRIVING the car as it says on a (possibly) existing birth certificate, and not deviating from it by 1/1000mm, are completely out of the question for me.


    AAAAAAbut:


    If you deliberately downgrade a K-Jet that matches the year of manufacture because it has too much new stuff on it -- and take a step back -- you can do everything FOR YOURSELF.


    None of my business or anyone else's here.


    Nevertheless, I would like to point out one thing -- nothing more -- just a thought-provoking suggestion:


    1. from then on, workshop visits are history.

    Because if a workshop realizes -- "Oops -- the wrong components are installed here -- I'll stop all work here now........"


    2. so all workshops are then closed forever.


    3. so you're forced -- not to be able to ask anyone.


    4. you can do it.


    5. if the car is ever sold -- do you put the "later K-Jet" back on before the sale?


    Or will the buyer be thrown out of all garages if there are problems with the K-Jet, or will they rebuild everything back to original for utopian money?


    For example -- I am speaking from workshop EXPERIENCE:

    For example, you order a fuel line from Porsche -- want to install it -- doesn't fit -- and then discover the "change".


    What is the workshop's mood then??????????


    Oh yes -- the fairy tale, my ass:

    "You can return the fuel line!"


    At P, returns are only possible above a certain amount.

    And the AG then decides what THEY want to pay YOU back.

    It's called a "buyback offer" -- meaning:


    Component cost €500 -- AG makes you an offer to then pay you 80% for it -- €100 in the barrel.

    We've been through it all -- and with even bigger "shortfalls".


    And you can still argue with the customer because he doesn't believe you...............................


    Nfu, Lars

    This post has been automatically translated.

    Nur wenn du schwarze Striche vom Kurvenausgang bis zum nächsten Bremspunkt ziehen kannst, hast du wirklich genug Leistung(Mark Donohue).


    Im Alter wird man immer knackiger -- da knackt es und da knackt es...


    Sechs 964er bisher mit abgerissenen Dilas --- 14(!!!) Ventilfederbrüche bei den letzten 5 Motoren! 4:3:3:1:3


    Porsche 911 -- der Volkssportwagen...


    "Hoffnung -- ist immer ein Mangel an Information!"


    Wer restauriert -- verliert...

    Edited 3 times, last by Ruf CTR ().