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    Rumorpile: Honda/Acura To Use A 9-Speed Automatic


    William Maley

    Editor/Reporter - CheersandGears.com

    March 22, 2012

    Recently, Honda's powertrain news has dealt with hybrids, direct-injection, stop-start, CVTs, and dual-clutch transmissions. One thing Honda hasn't talked about is what they're going to with their five and six-speed automatics. That could be changing.

    Automobile is reporting will likely adopt a 9-speed automatic by 2014 at the earliest. A source tells the magazine the 9-speed in question is from German supplier ZF.

    ZF's 9-speed is designed for transverse installations, which makes it suitable for front and all-wheel-drive vehicles. ZF says the transmission is capable of handling up to 354 lb-ft of torque, and can support both start/stop and hybrid drive systems.

    Automobile speculates the 9-speed could make its way to the Honda Odyssey, Pilot, Acura MDX, and TL due to the engines they're equipped with (3.5L and 3.7L V6).

    When asked for comment, Honda said the usual "we don't comment on future product plans" line.

    Source: Automobile

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    WOW, The Trannies are getting more and more complicated. I can only imagen the amount of work to rebuild one of these.

    This should make it really smooth shifting besides the usual fuel savings, etc.

    Makes one wonder if you have a 9 speed or 12 speed tranny, just what benefit you gain or loose by using CVT.

    I would think that the whole band running up and down the two cones of a CVT would not have the Torque capabilities of a traditional geared tranny.

    Anyone else have input as to the benefits of one over the other?

    Do we have the traditional CVT camp versus traditional tranny camp?

    I wish Honda/Acura the best as they really need to inject some much needed cutting edge technology into their products which are extremely stale to the point of Mothball smelling.

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    I am amazed that they say it would be 2014 at the earliest. I would think they would want to get it in ASAP.

    could take that long to ramp up production and testing/tuning may still be needed (building the cars to accept it too). how long did it take gm to get it's 6speeds in more than the corvette? i'm thinking at least 1 full year...?

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    You would think that they would be looking at ways to minimize time length by putting in place a process that can say change out at least 1 auto in 6 months with the latest tech such as this 9 speed tranny so that they can start marketing it to get sales and build excitement.

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    Are 9-speeds really that efficient? I remember that Lexus was going to 8-speeds and MB was going to 7-speeds relatively soon if not right now. One question: what are the gains from a 6-speed transmission? Is a CVT really that bad?

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    At some point having more speeds is actually less efficient. This is so for three fundamental reasons which are not fundamental engineering problems that can be solved.

    • While being in an optimal gear for a given speed and driving condition improves efficiency, the act of "shifting" itself reduces efficiency. During a shift, engine power is interupted and wasted as heat instead of providing propulsive force.
    • Having more speeds generally means driving more planetary gearsets (or in the case of dual clutch units more parallel shafts and gear pairs). Turning more gears -- even if most are not underload -- increases parasitic frictional loss.
    • With the same basic metalurgy, more speeds generally mean either a bigger, heavier transmission or one with a lower torque rating.

    At the end of the day, the question we need to ask is not how many speeds a transmission has. It is whether 1st gear can be low enough for maximum acceleration with the given rubber on the car, top gear is tall enough to give the lowest "drivable" crusing rpm on the freeway and in between there are enough speeds that a redline shift doesn't drop the engine revs outside the meat of the powerband.

    For engines with a high torque output and a broad power band, a 6 speed transmission may already do that. For some really peaky engines or engines with vvery narrow rev ranges (eg. Diesels), 8 speeds may not be enough for optimum performance.

    IMHO, an engine like a Small Block V8 in the Camaro and vette will not actually benefit from more speeds or a wider ratio spread. All they really need is a taller axle ratio to improve cruise economy. 1st gear acceleration may actually be better with a taller first except when wearing gumballs on a drag strip simply because melting the tires do not get you up to speed as briskly as just a tiny bit of slip.

    A turbocharged I4 like the 2.0T in the upcoming ATS and Malibu, will also not benefit much from having more speeds in the transmission. They will however benefit from an increase in the ratio spread from about 6.0 in the typical 6-speed box to the 7~7.5 range available in some 7~8 speed boxes. The gears themselves in the 7~8 speeders actually yield little benefit and are frequently skipped in actual operation.

    A peakier engine like the 3.0 and 3.6 DI V6es on the other hand can actually use an extra gear or two in addition to the widened ratio spread.

    The biggest problem with CVTs is that they rely on hydraulic pressure to clamp two pulleys onto a belt, chain or pivoting toroid. That hydraulic pressure is a lot higher than needed on clutches in automatics or dual clutch boxes because the CVT's chain or belt or toroid must, by design, make sharp and very narrow contact with the variator. A need for high hydraulic pressure means constantly driving powerful pump to supply that pressure which wastes energy. In many designs, CVTs are actually less efficient that traditional autos for this reason. The Ford 500 is a good example.

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    CVT's will continue to evolve...... i am sure a pittance of resources has been spent in the R&D and manufacture of CVT cars over 50+ years vs. traditional automatics.

    Nissan itself has made huge strides alone in the last 5 years. Versa mpg is up quite a bit. Look at the new Subarus. Believe me I know how they can feel rubbery especially if you are not used to driving them. Drive one a week or so and it gets more natural. Once they get the efficiency up and the programming better, and keep refining it, I believe you will see more and more cars go to it. Maybe not trucks and crossovers, but small to midsize cars. I think dual clutches will add use too, but boy I can tell you, FOrd has had a rough go of it with the Focus.

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    I will say this, the CVT are an interesting ride when you never hear the shift, it does make some wonder as I have had people comment on it when they drive a CVT for the first time. No shift points needed.

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