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rogcjms · 03-10-2007, 02:42 AM

Im curious about this since i have never dealt with one before. What exactly is it and how does it work? It seems like its almost like a manual tranny. Also seems like it will be more expensive as opposed to a manual...

foxtrot685 · 03-10-2007, 02:48 AM

it will be

but its like a manual, tap the plus to upshift, the minus to downshift. it wont downshift if the engine would end up over the redline. im not sure if this is the type of SM that will not shift for you, but instead hold that gear and just bounce off of the rev limiter...

rogcjms · 03-10-2007, 03:02 AM

basically its not like you normal Overdrive gear which you put it into and thats it. Do you actually have to shift in the auto? Seems like it would be better to get a manual. reason im asking is i may be planning on buying the new xB and wanted to know more about the transmissions. But im also looking into a tC...

superboxcarxb · 03-10-2007, 03:25 AM

i'm getting the manual trans xb2. i'll tell you what it's like when they come out.

CBSIMONSEZ · 03-10-2007, 10:51 AM

From what i understand; only cause i have never driven one, but you can drive it like an auto or a manual for more of a sporty response. Teh gear sellector actually goes into drive ... 2nd or 1st just like an auto tranny would in a box now. But with the paddle shift you can move up or down faster by your own hand rather then waiting for the converter to do it in the tranny. From what i gather its supposed to give you more of a sporty feel. Ferrari and now Audi have been doing this set up for quite some time. IMHO i think its over kill for a Scion regardless if its a xB2 or tC.

With the modifications i plan on doing, i have to go manual. I dont want to loose out on my added horse power by an ECU on an auto tranny with paddle shifters that wont allow me to shift when i want. In a manual, i can run it all the way out before i have to shift.

roXor_boXor · 03-10-2007, 12:43 PM

I have this in my Mazda3. If you are going to have an automatic it is definitely a plus. You choose when it shifts. You can run it clear up to the redline and against the rev limiter. Until you shift, it will not shift. As a safety, as someone else stated, if you try to downshift at a speed that would put it above the redline, it simply will not do it.

The place I really like having it is in a situation where I have a need to accelerate quickly. Say you are on a freeway on-ramp behind a slow car.

You can shift manually to control the rpms to keep the engine in the powerband. You avoid any hesitation of a down shift by the automatic and accelerate slightly faster.

With my Mazda in automatic mode with it in 4th gear going 35 behind the slowpoke the rpms at nearly idle. The powerband of the 3 starts about 3000 rpm. When you stomp on it it has to down shift (probably to 2nd) which has a noticeable hesitation and then it has to spin up to about 3000 rpm before you really take off.

Really the only thing you can do with a manual that you cannot do with this is rev it up and dump the clutch to launch the car.

Bottom line is that if you want or need an automatic this feature gives you the control of a manual for every situation unless you plan on racing it.

Hope that helps.

Giovanni · 03-10-2007, 01:14 PM

I have driven a few cars with sequential shift. On the high end, BMW M3 and Porsche Tiptronic to the low end hyundai tiburon. The development of this technology came from formula one racing and as such ferrari has had it for some time. It usually utilizes either hydraullic or electrohydraullic actuators to make the gear changes hence the speed advantage over regular manual. The other advantage is power. Most sequential set ups do away with torque converters and couple directly to the engine so there is no power lost in transfer.

Now, for the disadvantages, well......you get what you pay for. M3 SMG set up and the syncro of a hyundai are worlds apart, not only in terms of feel and performance but likely longevity and I for one dont want to have repair work done on a syncro $$$$$

At the end of the day if you are going to dive into new technology like SMT make sure you go with something well engineered for PERFORMANCE and not just for gimick.

Notacop · 03-11-2007, 04:18 PM

This is not a sequential manual. There is no clutch. No need for actuators like in the BMW and Porsche. No cool dual clutch like Audi and VW (DSG = Best transmission EVER)....

It is simply a normal automatic transmission with 1 extra feature. If you put it in drive it will drive EXACTLY like a normal auto transmission (not the case with a true SMG).

The extra feature is that you can go from normal "Drive" into "Manual Mode" which simply lets you tell the auto when to shift.

The transmission still utilizes a torque converter, so the shifts are only as fast as the auto tranny can make them, but you have control of when it happens.

You can use this to control downshifts going into turns, have it hold a gear, if you know that you are going to be slowing down soon (going around 'S' curves for example) and force shifts into higher gears if you are really pushing for the ultimate fuel economy.

I very nearly bought a VW GTI and a good portion of the reason was the DSG transmission. Do some reading on it, and you will see how awesome it is. I could only hope that all cars will eventually have this type of transmission, as one of my biggest gripes with auto transmissions is the inefficient torque converter.

In summary = Auto with "Manual Mode" != SMG

CBSIMONSEZ · 03-12-2007, 02:59 PM

IMHO it takes away from the "fun factor" in such a low end ride. If you had a Farreri then sure, get it. But on a Hyundai or even a Scion .. its just not needed. Dont be lazy, get the manual if you want to shift.

sciontcnj · 03-12-2007, 03:10 PM

[quote="CBSIMONSEZ"]IMHO it takes away from the "fun factor" in such a low end ride. If you had a Farreri then sure, get it. But on a Hyundai or even a Scion .. its just not needed. Dont be lazy, get the manual if you want to shift.[/quote]

Amen to that...im tired of hearing people talk about autostick like its the same as a manual....it is and then it isnt...like ive said before the next time i will be driving an automatic is when i am a member of AARP

Notacop · 03-12-2007, 05:02 PM

Yep even with the paddles it is still an auto.

The DSG I feel is 80% as good as a true manual. The thing going in the xB is only about 10% better than a normal auto, leaves another 90% lacking. These are just my opinion of course, no way to measure such a thing.

If you have not yet, go drive a VW with the DSG transmission. It is great.

toyotaisme · 03-20-2007, 08:02 PM

The simple way to explain it is like driving a stick shift without the clutch.

click on the article

http://auto.howstuffworks.com/sequen....htm/printable

Notacop · 03-20-2007, 08:09 PM

Quote:

Originally Posted by toyotaisme

The simple way to explain it is like driving a stick shift without the clutch.

Not even close. Torque converters are very different than clutches.

There are clutchless manuals, and they drive VERY differently than auto's with paddle shifters.

A torque converter uses hydraulic pressure to convert the engine power to movement. Under a certain RPM there is not enough pressure to turn the output side hard enough to overcome the brakes. This is why you can stop and not stall. When you give the car gas the input side of the converter spins faster than the output side, which generates enough pressure which causes the output side to spin with more force. The downside is that you lose a LOT of efficiency through heat and slipping (most slip 5% or so under normal driving). Most torque converters have a lockup function that will lock the input/output sides of the converter at cruising speeds. This helps abate some of the loss

A clutch is a way to disconnect the engine from the transmission completely by depressing the clutch pedal. When you start to go you have you slowly release the pedal to allow the clutch to progressively grab and transition you to rolling. When the pedal is depressed it is 100% disconnected. When the pedal is released it is 100% engaged.

Next major difference is that most auto transmissions use Belts/Bands to engage the "gears" whereas most manual transmissions have actual gears.

Manual transmissions are generally more compact and lightweight as well.

So basically. No. It is not like a manual without a clutch. Sorry not trying to be a jerk but want to make sure everyone knows that there is a MAJOR difference between the two.

The link you provided is to a true sequential shifting manual transmission. Very different from what is going in the new xB.

vintage42 · 03-31-2007, 08:48 PM

Have I got this straight:

The new xB will have a regular automatic transmission that can also withstand you making it change gears up and down with the shifter. Not all automatics can take that kind of operation.

Then there are DSG transmissions where clutches and gears are operated by electric actuators. SM shifting can either be automatically left to the car, or can be manually controlled by paddles on the steering wheel. There is no gear shft lever or clutch pedal. When you move a paddle, actuators work the clutch and the gear linkage.

Both transmissions can shift automatically or manually. But one transmission is an automatic behind a torque converter, and the other is a gearbox behind a clutch.

roXor_boXor · 03-31-2007, 11:32 PM

Everything I have seen indicates a simple automatic trans that can be shifted manually.

As I stated earlier, they have some advantages over plain automatics, but not that big of a deal. Definitely not the same as the "manual" version like you described.

Notacop · 04-01-2007, 04:55 AM

Exactly!

DriverXa · 04-01-2007, 05:02 AM

Notacop has pretty much explained it. All the tiptronic feature is a manual gear selection option on a standard automatic transmission. Instead of having L2DOD u have a D and S+/-. D is regular automatic mode while the S means sport and gives u the option to tell the car what to be in instead of the automatic trans doing it the way its designed to do, if u want to put it in a better sense think of a th350 trans with a shiftkit. U can put the selector in anygear u want and itll upshift or downshift for u at will. Now on some cars like early BMWs the sequential mode had a sport mode which changed the characteristics of the caar abit, not muhh but noticable. It also had a sport shift where u left it in automatic mode but shiftpoints and firmness were change aswell. All this is is a cheap gimmic to make u gell like ur shifting the car. To get true performance get either a manual trans or a DSG setup. Automatics have their purpose and there good for dragracing where consistent launches and shifting can determine if u win or lose, thats the only application I'll ever drive an automtic again.

Notacop · 04-01-2007, 05:20 AM

I agree. If I ever get to a point where i don't want to mess with 3 pedals anymore it will be a DSG for me.

If you have not driven one, go check out the new GTI with the DSG, it is a blast to drive.

ApostolicFire · 04-30-2007, 02:44 AM

Quote:

Originally Posted by Notacop

I agree. If I ever get to a point where i don't want to mess with 3 pedals anymore it will be a DSG for me.

If you have not driven one, go check out the new GTI with the DSG, it is a blast to drive.

Also the 2008 Mitsubishi Lancer Evolution will have a similar transmission. http://www.edmunds.com/insideline/do...leId=119065#22 *wonders if he should try to get one*

grizzly_choppers · 04-30-2007, 04:13 AM

Wow, you guys are all making this way too hard. If you want to know what the 2008 xB auto tranny is like go test drive an Avalon or the new Tundra. They work the same way.

I've driven it and it functions the same in the xB as in both the Avalon and Tundra (with a different number of gears, of course).

-Alex