Does sequential shift help in FE

[appuchan]

Guys,

I am looking to buy a sedan here in India. We dont have so many options and I have sort of short listed to Honda Civic, Toyota Corolla Altis and VW Jetta. I am looking for an Auto transmission model. I have done detailed test drives of all the models and now its between Civic and Altis. Between them, Civic comes with a paddle shift mechanism which mimics a manual transmission to some extend. But it does auto shift at the top end of the RPMs, similar to Sport mode. Corolla Altis comes with a sequential shift option on the gear lever. It however doesnt auto shift.

I believe Altis provides the FE advantages of a manual transmission car while also providing the drive-ability of an Auto. I would like your comments on this. My main question is,

Is Sequential shift option, as in Corolla Altis, comparable to a manual transmission car when it comes to Fuel Economy.

My purchase decision will depend on this.

[dremd]

On a turbo Diesel car it definitely would improve fuel economy.

Otherwise; it would just allow a smaller engine to be used and maintain the same 0-60 as far as I can think of . . . .

[Ryland]

the big advantage of a manual transmission is that it has gears in it instead of a torque converter, so unless the tranny you are looking at is one of the few that really does shift between gears with dual clutches.
the only the reason that an automatic might get better mileage then it's manual counter part is that some manual trannies are geared towards the sport end and not the mpg end, and that some automatics are geared higher but can kick down if more power is needed.

[cfg83]

appuchan -

I agree with Ryland. Also, even if you have paddle shifters, I have heard that the control software in the car may override your choice. In this situation, you will be fighting with the car to stay in the top gear (I think this is what you are describing in the Civic). I would take a serious test drive where I try to keep it in top gear as much as possible.

From your description, it sound like the Altis will at least *stay* in the gear of your choice.

CarloSW2

[Geebee]

Hondas CVT's with paddle shifters do not have a torque converter and in auto archeive better fuel economy than their manual conter parts by more effeicient gear ratios.
Having said that a full manual is the best bet for hypermiling due to non standard drive train use.

[appuchan]

I am not sure if regular Honda Civic has a CVT transmission. I think it is available only for Civic Hybrid. A hybrid car is ruled out here in India because of the high cost. Civic Hybrid here is a fully imported car and costs equivalent to USD 50K!

The paddle shifters do auto shift up and down at specified RPMs and does not actually mimic a manual transmission system. Altis shifter at least seem to stay in the gear during my test drive. I hope this means slightly better FE. Unfortunately the sales guys were not knowledgeable enough to explain the functioning clearly other than just parroting "better FE than Civic paddle shift".

[Geebee]

The Jazz/Fit had it as well but they discontinued it this year as they say people don't like it.
We have a CVT Jazz and the gearbox is the best automatic I have ever driven, smooth as silk, perfect match to engine, BUT it does have one drawback and it maybe why it was discontinued you cannot tell what speed you are doing by engine sound as the speed can vary markedly via the gear box with no engine noise/rev change. Takes a lot of adjusting to.
Having said all that I gave the Jazz to the wife and bought an 8 year old Daihatsu Sirion GTVi manual, much more entertaining to drive.

[extragoode]

Like everyone is saying, it's not as simple as manual and automatic transmissions anymore so it doesn't do anyone any good to try and force the current options into these two categories. At the very least there is manual(physical gearbox with no electronics besides neutral detection and a tachometer), automatic(torque converter with electronic shifting based on hydraulics and bands, controlled by the ECU), and CVT(constantly variable transmission, used in a lot of hybrids, engine is connected to a belt system that allows for any gear ratio in fairly wide range, ratios are controlled by ECU), and at worst there are multiple variations on these like autostick(regular automatic with the option of telling it to shift up or down, but it can and will ignore you), and paddle shifted CVT(regular CVT, but paddles shift to predefined ratios programmed into the ECU) which sounds like the setup on the alti you're talking about. I know the '08 lancer has the paddle CVT option. A real sequencial transmission is like what is on a motorcycle. I'd love to have one, but I've never found a true one on a street legal car.

Now which ones better for FE? That depends the most on you, the engine this trans is plugged into, and the ratios available in this trans. An auto as described above is almost always the the worst of the three because of the torque converter, therefore if you don't want to have to shift for yourselft the best option is usually some flavor of CVT since most of them are capable of astonishingly high gear ratios. If you drive mostly city miles or for some reason the regular manual has a higher possible ratio than the CVT, go that route. Overall, I'd say do some more research and go with the option that allows the highest gear ratio to be chosen by YOU. Like I said, CVTs usually have huge POSSIBLE ratios, but often will only let you use something significantly less unless you're coasting. Also, all this is strictly from the point of view of FE. There some concerns for the service length of CVTs, so for overall value on a car it might still be worthwhile to chose one with slightly lower FE in favor of longevity and warranty. I prefer the good old manual with it's cheap maintence/replacement and a general lack of a need for said maintence/replacement.