It's official. Manual transmissions are making a comeback.

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There are lots of great statistics at the Government CAFE web site. Lots of compiled data on cars going back to 1977 (and some even older.) One interesting trend tracked is the percentage of
automobiles with automatic transmissions.
In 1977, 84.1% of all new cars had AT. Under pressure of demands for improved fuel economy and increasing consumer preference for import cars, that number dropped to 75.0% in 1987. Then imports went upscale, ATs became more sophisticated and fuel got cheap. By 2002, 88.5% of new cars had only two pedals and the imminent demise of the manual transmission was widely predicted.
Then something funny happened. There were rumors of rebellion in the ranks and increased reports of drivers demanding control of the gear ratios. In 2003, the percentage of cars sold with automatics dropped precipitously to 82.4%. The CAFE site is now reporting a further drop in 2004 with the lowest percentage of AT's since 1991, 79.6%. That means that the number of cars sold with manual transmissions increased 77% in only two years and a clutch is now found in one of every five new cars.
In terms of sales, this trend actually surpasses the much touted return of rear wheel drive and the movement is broad based. While keeping in mind that the politics of fuel economy can skew the definitions pretty badly, the trend is apparent in domestics, Asian and European imports. All are selling manual transmissions at levels that haven't been seen in a decade. Almost half of all European cars are now shifters, the highest rate since 1988.
Will this be a long lasting trend or a brief flash? It is still too early to tell but it certainly shows that the old MT is going to be harder to kill than it once appeared. The auto companies have now learned that there is a solid base of buyers who prefer to shift for themselves and the increased availability of this option is sure to follow.
http://www.nhtsa.dot.gov/cars/rules/cafe/NewPassengerCarFleet.htm
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snipped-for-privacy@mindspring.com (Gordon McGrew) wrote:

On the other hand, you can't have hybrid gas/electric with MT. It's kind of a bummer because I like responsiveness of manuals but the milage*power level is falling behind some automatics. Regenerative braking, continuous gear ratios, ultra-lean burn, and cylinder bypassing need to be coordinated with an AT. The decision was much more clear-cut a few years ago when you chose between a peppy 5-speed manual or a sluggish 3-speed automatic. Now cars like the Accord Hybrid make the decision tough.
If we get fuel cells in marketable condition there may not be multiple gears anymore. You'll just have a knob to select how much regenerative braking you want when you take your foot off the throttle. Crank up regenerative braking and you'd have lightning fast response to throttle changes.
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On Thu, 24 Mar 2005 22:05:51 -0800, Kevin McMurtrie

Sure you can. Both the Civic and Insight hybrid models are available with MT. Accord hybrid comes only with AT for now, but you can get an MT on your V6 Accord now so it isn't implausible that the hybrid may get it eventually.

I think that it will be a long time before fuel cell cars are any more than a curiosity.
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shhhhhhh......don't tell Honda, who sells them by the boatload with manual transmissions.....
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wrote:

a manual; in fact, it can't have any transmission at all. It has an "electronic cvt" that is really just a pair of motor/generators in a differential arrangement with the gas engine... there is no place to put a transmission in the power train. If it were called a "virtual cvt" it would be less confusing.
Honda's IMA (integrated motor assist) works fine with a manual; Toyotas SHS (synergy hybrid system) could never have one, if only because the driver has no control over whether the engine is even running.
Mike
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Well, I guess it depends on your definition of "transmission", but I'd definitely say they have one! They have a set of planetary gears (which automatic transmissions also use). And yes, as you wrote, motor/generator is used to modify the gear ratio between the ICE and the driveshaft, as well as supply torque.
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Describe that a little more, if you would. I have a Honda Civic Hybrid with CVT, and I understand how it works. The IMA is fixed to the crankshaft, so they are both turning at the same speed. The CVT is a steel belt on movable "pinch" pulleys to provide the variable ratio.
I don't understand the mix of two electric motors and the CVT in the Escape. Short of buying the service manual, can you point to a decent reference for how it really works? I've seen some misguided crud, but no real explanation. I assume that it is the same as the Prius, so reference to that would be good, unless I can spot a discrepancy.
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wrote:

The Escape uses pretty much the same system as what Toyota uses, which is way different than the straightforward Honda Integrated Motor Assist.
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Try this treatise: http://home.earthlink . net/~graham1/MyToyotaPrius/Understanding/PowerSplitDevice.htm
I can't vouch for it being 100% correct, but it is similar to what I've read before about the Toyota hybrid drive. Basically, by varying the motor/generator1 speed, one can control the ICE rpm.
It's pretty neat, but also complex. 2 high-power motor/generators.
Another reference: http://www.me.utexas.edu/~tomr/body.htm
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that he looked into it very carefully, and it is true - under many conditions MG1 is used as a generator to provide power to MG2. It makes my head hurt to visualize it.
Mike
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Yep. That's how you can have a 50 kW motor, but only a 25 (30?) kW battery driving it. Sometimes, actually quite often, at least part of the electric power to drive the second motor comes from the ICE driving the first motor as a generator. Basically, an electric transmission. Generally I would not expect that to be as efficient as a mechanical clutch.
So the Prius system acts as both a mechanical and electrical transmission.
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wrote:

The efficiency is supposed to be about 90%, considerably less than a manual gearbox. OTOH, it allows the engine to operate in more efficient ranges more of the time, so it's an overall gain in city driving. On the freeway it would be hard to beat a manual tranny for efficiency. (I understand ATs with lockup come close.)
There is a narrow speed/power mode where MG1 is stationary and the transmission is strictly mechanical. I think that speed is different in the first generation Prius (before 2004 MY) than with the second generation, because the MG maximum speeds are different now.
Mike
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Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8,-122.5
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That has a drawing of a "conventional" (Honda-like) CVT that made me think the article was all wrong. It's a paragraph or two later that it explains the Toyota PSD, but even then the picture is wrong. It looks like the MG1 and CE are slaved on a single shaft.

<http://home.earthlink.net/~graham1/MyToyotaPrius/Understanding/PowerSplitDevice.htm
That made interesting reading. Doesn't cover all of the operation, but I can fill in the rest... MG1 must be the "starter motor". MG2 supplies regen braking. But I think I understand it now... The oddities are compromises. It all makes sense.
The Honda Charge/Assist displays what I expect it to display. When I floor the gas pedal, the assist goes full, and stays there. Because the IMA has a power peak at 4000 RPM, I would really expect the bar graph to drop off some above 4000 engine RPM, but maybe that's literary license for the masses, who wouldn't want the graph to reduce while demand is full.
In the Escape, flooring it gives near full assist for a little bit, then swings to charge. That confused me, but it is clearer now. That only happens at higher speeds. (I actually went out and drove the Escape to test my new thoughts.) It is because MG2 is tied to the wheels, and has a peak power at some road speed. I might guess that it's 47mph, where the EPA highway test runs ;-) It is above thirty, and less than sixty. At about 10mph, going up a steep hill, flooring it leaves it at full assist, like I would expect, for the duration of my little test run.
The Escape ICE seems to go to about 4,000 RPM under almost any enthusiastic "gas pedal" position. The MG2 speed would change exactly as the road speed changed, with good power up to a road speed that I could calculate if I went back to Graham's page. The MG1 RPM would change inversely as the road speed increased if the engine stayed at 4,000 RPM.
I don't see how it relates to the "combined HP" being less than additive between the MG2 and the ICE. The MG2 maximum would be related to road speed. The ICE could be held at its maximum HP, and the RPM of that has little to do with the RPM of MG2. The MG1 output would be lower as ICE went higher, so there would eventually be some electrical starvation as the batteries depleted, but it seems that you should be able to see maximum MG2 horsepower added to the maximum ICE horsepower, at least for a few seconds, and maybe only at one particular road speed.
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Yep - forget about that site. It's pretty messed up. It also describes the SHS as having two 67 hp motors, while MG1 is about half that capacity.

MG2, and regen braking is almost exclusively MG2. Reverse is MG2 all the way. When driving, MG1 is primarily responsible for controlling the engine load (virtual gear ratio), and it is in that role it operates as a generator.

MG1 to MG2. That part limits the power of the system because the power can only be counted once. For example, if you have a 100 hp engine and a 50 hp motor, but at full power 20 hp of the motor output comes from the engine through MG1 (rather than from the battery) the total is only 130 hp.
Mike
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I had heard that. But at stall, that's 94 HP, isn't it? I've heard of people getting stuck in potholes, because they couldn't move forward and didn't have the power to move backward. I was trying to decide how I could test for that.

I've heard that this power arrangement, where MG1 is draining power during highest power demand, is due in part to the battery not having enough of an amperage rating to drive MG2 at full power, but I wonder about that. Maybe it just isn't efficeient to run at full power from the batteries for very long, due to the total amp-hours available, and a balance has been found that is more efficient.
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As with all cars, it's zero hp at stall (any force times zero distance). However, the full electric torque is available. The torque is considerable - 295 ft-lb compared with the rated 82 ft-lb from the engine - so the stories of getting stuck in potholes are urban legend. (But note the torques aren't directly comparable because of the effect of the power split device... the electric provides something like 2/3 of the torque at the wheels.) At any rate, I can attest from our 40K miles experience with a 2002 model it just isn't a problem.

that the hybrid computer gets the command from the accelerator and brake pedals to go so much or stop so much, and it calls on the engine or batteries to make it happen according to the hybrid computer's programing. For example, in the earlier generation if more than 9 KW was needed the engine would fire up. In the current generation it is some slightly higher figure I don't remember.
As far as the generation by MG1, it is easiest to think of it as the way it provides the prescribed load to the engine. That's how the "ECVT" does it thing.
It certainly illustrates why the "ECVT" can't be replaced by a manual transmission. The engine is a resource of the hybrid computer and is only under the most indirect control of the driver... about the way your heart rate is under your control. I can floor the accelerator with the shifter in "park" and hold it there. The engine gradually revs, reaching a peak of 2250 rpm in a couple of minutes. Imagine trying to shift that arrangement.
Mike
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I have an Escape, so the "2002 model" caught me off guard there. The getting stuck part is being written as first hand in the Edmunds forum.
It is said that applying throttle slowly doesn't work, because of overload sensing. I have gotten "stuck" in a small ditch on my property. I seemed stuck, but I had read the posting, so I got "more aggressive" with the throttle. I might go try it again, with a normally cautious application of power, and see if the motor gives up.

I had toyed with the lack of response, but hadn't held it there...
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older Toyota Hybrid System (THS), like in our 2002 Prius, the hybrid computer handles wheel spin in an unsophisticated version of traction control. In snow for example, we just push the throttle down somewhat and the system does a sort of slow ABS in reverse, cutting power for perhaps 1/2 second when it detects wheel spin. It works well for slippery starts and slippery hills. Apparently the Synergy Hybrid System (SHS) Toyota has made since 2004 MY (and licensed to Ford for the Escape) responds by shutting down power completely at ordinary throttle settings, leaving the driver sitting until the throttle is either released or floored. I'm told the behavior at full throttle is what I'm used to at any throttle setting. I don't think I'd like the new way, and I don't know why Toyota changed the hybrid computer program. I'd think having the accelerator floored when finally getting to good road surface could be unsettling.
What surprises me is that the hybrid computer could be programmed for the most intelligent way of handling wheel spin. The computer tightly controls the MG2 speed; why isn't it programmed to calculate the friction it encounters and adjust to the best torque for the conditions? It could even be programmed to rock safely out of a hole, something that is forbidden to the driver in the Prius (and many modern cars - my daughter's '93 Accord expressly forbids it too.) It would require a special "gear" (selection on the shifter - there are no gears anyway) and some lines of code but it would be a boon. It could be far more effective than even the most experienced driver, because it could control torque instantaneously and map the friction contour of the hole as it worked. Maybe someday....
Mike
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wrote:

By that way of looking at it, SHS has two transmissions, like pretty much all cars. The planetary "power split device" is a skewed differential and could have been made like a typical differential if ruggedness weren't important. No gears ever shift, there are no clutches or belts or hydraulics or solenoids or forks. It is all fixed gearing, which makes it different from automatic transmissions. The device should be bulletproof as long as the lubricant is kept up, without the weaknesses of manual trannies (no synchros, no clutch, no gear crunches possible).
The way I describe the system is to visualize an engine connected straight through to a differential. Instead of wheels, there is a motor/generator on each side of that differential. Connect another conventional differential and wheel setup to one side, and there you have it.
Mike
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