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The most misunderstood aspect of the Toyota hybrid synergy drive system

Discussion in 'Gen 5 Prius Technical Discussion' started by Paul Gregory, Jun 30, 2024 at 10:55 PM.

  1. fuzzy1

    fuzzy1 Senior Member

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    My 2024 is much quieter and smoother in spinning up for light engine braking than were my 2010 and 2012, despite having a larger engine. I need the tach to be certain.

    That is so 20th Century. Those of us quoting engine-braking RPMs here for various operating conditions, have used the 21st Century method, which as Chap noted, was available in all U.S.-market cars a handful of years before the 21st Century actually arrived.

    Most people don't have to prove themself to themself.
     
  2. KMO

    KMO Senior Member

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    Ah, now THAT's an interesting nugget.

    I had hypothesised that maybe B did something that D could not, in that engine braking strength was determined by the D/B selection.

    In normal use, we know regen could substitute for brake action on a pedal press, and regen or engine braking could subsitute for simulated transmission drag.

    What I didn't know was whether engine braking could substitute for brake action like regen can. Maybe it only engine braked up to the transmission setting, and the brake pedal could only affect brake pads if regen was unavailable, so B was significant to give you more engine braking, and could help your brake pads.

    But if the engine revs up to give more engine drag when you press the brake pedal in D, then that suggests the whole "braking+drag" system is fully integrated, and it seems B really doesn't do anything D can't. (Apart from the legal safety aspect of "what if something happens to the driver and they release the pedals").
     
    #62 KMO, Jul 3, 2024 at 6:48 AM
    Last edited: Jul 3, 2024 at 7:15 AM