Automobile Transmission, why not?

Discussion in 'DIY Marinizing' started by Ken Gasch, Oct 5, 2004.

  1. powerabout
    Joined: Nov 2007
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    powerabout Senior Member

    Certainly makes sense with a diesel as low load in top gear you can get the effect of a cpp and full power you drop down the gears so you dont overload the engine.
    For petrol you can use the gear ratios for more acceleration
  2. boat fan
    Joined: Sep 2008
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    boat fan Senior Member

    Correct. It was an Allan Jones ( ex Australian Formula One world champion ) hull.He had the molds.He built them on the Gold Coast at the time.
    I do remember that Vince put in Huge longitudinal Girders.
  3. crowsridge
    Joined: Apr 2010
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    crowsridge Senior Member

    Im very interested in this thread. Id like to put twin vw diesels in my 23' semi planing hull. My supplier has done it before he says. He used the vw auto transmission. Since theyre sideways, I can turn the oppsing each other to get my counter rotations.

    Id like to run closed cooling with radiator and electric fan like he put in his Samuri conversion. Dry stack exhaust up behind pilot house. Thinking of putting radiator on top laying flat and have cooling lines run in chase. Tap in lines to have heat in PH too.

    Keep the info coming. Pictures would be great!

  4. broke_not
    Joined: Jun 2008
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    broke_not Junior Member

    Park pawls do a good job at holding a shaft once it's already stopped, but they don't stop shafts from rotating all that well. If they did, transmission shops would be busy replacing them, (as well as other damaged driveline components), when folks shifted into park while moving accidentally. If the transmission output shaft is turning and you shift into park, you'll hear an annoying ratcheting noise...the pawl does nothing "effective" until the shaft slows enough/comes to a stop, and it can then drop into a recess to hold the shaft stationary.

    Not saying a park pawl wouldn't be handy in a boat, but I'd put an electrically-operated clutch of some sort on the output shaft to stop the shaft once it was shifted into neutral. I wouldn't rely on a park pawl to do it day-in day-out.

    1 person likes this.
  5. Frosty

    Frosty Previous Member

    Park pauls do beak off and transission shops do replace them. The picture is not of an automatic transmission, a park paul in a automotive tranny is much smaller and will not select with the weight of the car rolling untill 7mph when it comes in with a bang and usually breaks the tooth off.

    Stopping a turning prop would not be a problem. Some trannys have the pump at the front that work immediately when the engine starts --some have two --one at the back these vehicles can be bump started and do not suffer from towing( too far)

    Hoever a light weightvw/audi auto will be made no stronger than it needs to be and for any serious sea work will be insufficient.
  6. eyschulman
    Joined: Jul 2011
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    eyschulman Senior Member

    You might ask some old timer crab or lobster fishermen. I think they used to use big block car and truck motors.
  7. broke_not
    Joined: Jun 2008
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    broke_not Junior Member

  8. Frosty

    Frosty Previous Member

    That paul looks to me as some kind of industrial transmission like that of a fork lift. In the auto trannies I used to overhaul they are much smaller than that. I am not familair with a C4 or 7.2 liter American V8's which is not what the conversation is about.

    That paul is huge and is not what you would find in a little VW Audi tranverse
  9. broke_not
    Joined: Jun 2008
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    broke_not Junior Member

    But it's not. It's out of an extremely common C-4 automobile automatic.

    I guess it's evident then that there are examples you haven't seen.

    The C-4 is most certainly an automobile automatic transmission, and a very popular one at that. Since the thread topic reads, "Autombile transmission, why not?", I'd say that automotive transmissions are VERY MUCH what the conversation is about. When you mentioned the 7.2 liter American V8s, it's worth noting that you're the one that mentioned it. I didn't. Are you attempting to deflect attention away from your matter-of-fact, (and incorrect), earlier statement about the photo, by alleging that I'm the one changing the subject here?

    I didn't post the photo and say it was a component you'd find in a "VW Audi transverse". I called it a parking pawl...which it is. I said where it can be found....and provided a link.

    So there you go.

  10. Frosty

    Frosty Previous Member

    Then we agree --that paul is not what you would find In a VW or Audi transverse transission.

    I am NOT familiar with a C4,--correct.

    So--any one thinking that the sturdy and very well engineered paul in the picture is not in fact what you would get in and Audi,--hows that,-- OK?
  11. broke_not
    Joined: Jun 2008
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    broke_not Junior Member

    Yeah, once again...nice try.

    Read my original post. Then read your original reply.

    Then read my follow-up, and your follow-up.

    You could have just said right off the bat that you were mistaken, but the further this progresses, it becomes increasingly obvious that that's something you're not comfortable admitting. Another approach would have been to look at the photo and ask what it actually was, instead of saying what it wasn't....especially since it's something you're not familiar with.

  12. Frosty

    Frosty Previous Member

    Your 100% correct absolutely I am wrong Your right in everything you say and are right in what you are going to say for the next 100 years .

    Is that OK?

    BUT--- that paul is NOT what you will find in an Audi --IS IT?

    So what will you do about the modulator valve on your auto /marine tranny.

    Would you alter line pressure-or maybe remove and block the governor.

    Ille give you time to google it up.
  13. whitepointer23

    whitepointer23 Previous Member

    if you read my post on the subject i mentioned c4 and c6 gearboxs , they are what my friend has used in boats for years and they perform well. he has never had a problem selecting park or with the shaft spinning in neutral.
  14. Frosty

    Frosty Previous Member

    With the massive paul on that picture of the C4 im not surprised.

  15. whitepointer23

    whitepointer23 Previous Member

    don't worry about all your modulator and control theories because it is bull##it. these trannys work fine without modifying anything. i don't know what would happen with the vw trans , i have never seen one.
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