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Constant RPM gearbox?

  1. Dec 2, 2006 #1
    So I'm driving this super mini on diesel and I observe several differences with normal petrol cars.

    At low RPM, some 1700-2000 cycles, the engine is super effective, the torque and the excess power is awesome, while the fuel consumption is unreal low. However at higher RPM, this surplus decreases vastly and above 3500 RPM, normal petrol cars seem to prevail for horsepower and fuel consumption. Obviously with a diesel, you'd like to drive at 1800-1900 RPM all time for optimum performance and minimum fuel consumption.

    So how to construct the constant RPM gearbox, making sure that the engine runs at optimum torque all the time?

    Can we revive the old DAF Variomatic from the moth balls?

    http://www.classic-daf.nl/indexb.html [Broken]
    http://www.tocmp.com/pix/Europe/DAF/pages/1962 variomatic_jpg.htm
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Dec 2, 2006 #2


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    While the DAF variomatic isn't the ideal setup, there are many cars with continuously variable transmissions (CVTs) available today (from the Fiat Punto to the Audi A6).

    This Wikipedia article is excellent for detailing the different types of CVT and their associated mechanisms.
  4. Dec 4, 2006 #3


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