Best Semi-Auto Shift Systems

They're completely different systems. The Ferrari system is a single clutch, automated manual and the PDK is a dual-clutch pre-selector style similar to the Audi DSG/S-Tronic gearbox that has been out for years and the BMW DCT that was recently launched on the M3 and will be available on the 335i and Z4 sDrive35i.

I believe the AMG speedshift is similar to the Aston system (and others) in being an automatic with a paddleshift to select pre-defined ratios. Most reviews suggest this gives a smoother shift, although IMO it's cheating a bit since it's still an automatic with a torque converter. So it's solving a deficit in new technology by using old technology.

I think the new California has a double clutch gearbox, indicating that this is the way that the paddle-shift transmissions are heading as more and more are adopting this idea in place of normal automatic gearboxes.

I agree though that paddles mounted to the wheels are better than those on the column or buttons, but I couldn't really say that AMG has the best ones (personally I preferred those in the M3 M-DCT to the C63 AMG, but I'm sure it varies by model). My preference is for two paddles, left = down, right = up attached to the steering wheel. This to me is an F1 style gearshift and ultimately that's the point of paddles, to emulate that driving ergonomics. The way that Porsche and the non-M BMW's have it arranged just seems strange to me.

 

i don't know if semi-auto is the best terminology.

there seems to be a consensus that DSG style gearboxes are the best. disadvantage is some added weight.

 

I have the DSG in my Audi TT. It works as advertised -- very smooth, much better than the 355 and 360 F1 systems. Haven't driven an F430 F1, so can't compare. In full automatic mode, it's not as smooth as a pure automatic, but very usable in traffic.

I haven't driven the Porsche PDK yet, but have a Cayman PDK test drive scheduled in a couple of weeks when they have one to demo. I expect I won't like the buttons as much as the paddles Audi uses.

"Semi-auto" is probably the right terminology -- these newer gearboxes manage the throttle for you during a shift, and they can be set to behave as traditional automatics.

 

I don't think you want to be up/down shifting while in a turn.

 

You don't want to have to slow down as you turn either.

 

These systems were designed for people with severe handicaps, which in most likelihood would be Americans.

 

Yeah, like that Schumacher guy from wherever.

 

+1

 

IMO the F1 Superfast in the 612 OTO and especially the Scuderia is superb, seamless.

 

It also depends which AMG Speedshift transmisison you are talking about. They all use conventional torque converters except for the special MCT version in the SL63. It is a multi-clutch system with a wet clutch and 4 shifting modes with launch control. I've driven this car with this gearbox.......shift from 7th to 4th under full power and be prepared to use a neck brace for 2 weeks, as well as get your stomach unravelled from around your spine.

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The AMG SPEEDSHIFT MCT 7-speed sports transmission is an all-new, unique concept, available exclusively in the new Mercedes-Benz SL 63 AMG. It combines the best of two worlds: the sporty, direct and agile feedback of a manual transmission and the maximum convenience of an automatic transmission. Fitted with seven speeds, four drive modes, a double-declutching and Race Start function, the AMG SPEEDSHIFT MCT 7?speed sports transmission offers unprecedented versatility. MCT stands for Multi-Clutch Technology and only employs clutch elements to perform gearshifts.

The high-tech transmission is designed for high torque and maximum revs up to 7200 rpm. It also comes with sufficient reserves even under the highest loads thanks to its high-performance oil cooling system. An all-new, sophisticated electronic transmission control unit fully controls and monitors all processes. A new two-stage torsion damper effectively eliminates vibrations. The AMG SPEEDSHIFT MCT 7-speed sports transmission has been developed jointly by Mercedes-AMG GmbH and Daimler AG, although it will be used exclusively in AMG high-performance vehicles. It is produced at the Mercedes-Benz Esslingen-Hedelfingen production facility, Europe’s largest manufacturer of planetary gear sets.

Four drive modes for tailor-made driving pleasure.

At the heart of the new AMG SPEEDSHIFT MCT 7-speed sports transmission lies the wet start-up clutch, which runs in an oil bath and replaces the previous torque converter. Thanks to its low rotational inertia, the transmission responds instantaneously and dynamically with no slip. Accelerator pedal movements trigger an instant traction response. Fitted with four drive modes: “C” (Comfort), “S” (Sport), “S+” (Sport plus) and “M” (Manual), the transmission provides gearshifting with no loss of tractive force and supports customised control strategies for maximum driving pleasure. In “C” mode the gearshifts are comfortable, coupled with a “soft” accelerator response set-up for outstandingly smooth power transfer. In “S” mode the engine and transmission interact with more "bite": the engine speed is allowed to reach a higher level in each gear; the downshifts also feel more spontaneous. The gearshifts are around 20 per cent faster than in “C” mode. Switching to “S+” mode cuts another 20 per cent off shift times, while “M” is the sportiest mode: here the AMG 6.3-litre V8 engine has even more bite, added to which the transmission shifts gear another 10 per cent faster – a reduction of 50 per cent compared with “C” mode. In “M” mode the gearshifts take just 100 milliseconds.

Ultra-fast, spontaneous multiple downshifts are another forte of the new MCT sports transmission. For instance, kickdown lets you move straight from seventh down to fourth gear or from fifth to second. In the “S” (Sport), “S+” (Sport plus) and “M” (Manual) modes the automatic double-declutching function is active. Every manual or automatic downshift is accompanied by precisely metered double-declutching – from “S” through “S+” to “M” incrementally. And this not only adds to the driver's emotional experience: the virtually load-free downshift minimises load-change reactions, which pays dividends particularly when braking into a bend on the

New AMG DRIVE UNIT with innovative Race Start function.

The new AMG DRIVE UNIT is the central control unit for the AMG SPEEDSHIFT MCT 7-speed sports transmission and all driving dynamics functions. The driver can change gears either using the new AMG selector lever with its leather/carbon-fibre finish, or by nudging the AMG steering-wheel shift paddles. On the left next to the selector lever is the electronic rotary switch to select the four drive modes including activation of the new Race Start function. Underneath are three buttons for additional functions: the first controls the ESP function, the second the ABC suspension system. The third adorned with AMG lettering is used to store the selected transmission drive mode and the suspension set-up. Briefly pressing the AMG button brings up the configuration options, while holding down the button allows you to program the required set-ups.

The Race Start function takes driving dynamics to an entirely new level: it enables the SL 63 AMG driver to call on maximum acceleration, while ensuring optimum traction of the driven wheels. While the vehicle is at a standstill, the driver needs to activate the ESPÒ sports function and press the brake pedal with their left foot. Having preselected the Race Start program using the rotary switch, a confirmation message comes up on the AMG central display. The driver then simply needs to confirm the Race Start function by pulling the “Up” shift paddle once, fully depressing the accelerator and taking their foot off the brakes. The optimum start-up engine speed is set fully automatically and the SL 63 AMG accelerates away in an instant – as an option even up to the top speed. The driver does not need to shift gear manually; the AMG transmission changes gear with lightning-fast shift times.

 

I haven't driven a 612 OTO or a Scuderia, but I was surprised at how not seamless the shifting in the two 599s I drove was. I was expecting it to have no noticeable lag and not jerk at all, but there is lag and the car does jerk. Granted, it happens incredibly quickly, but still not perfectly. I imagine a dual-clutch setup would eliminate any such lag and jerking.

 

please note that the gearboxes in F1 cars are not at all like the F1 shifter/gearbox in a street car.

and driving a race car is nothing like driving a street car. it's not just driving faster.

 

no way, you can get yourself into big trouble. you downshift in the straight part of the braking zone.

upshift in a turn is ok ... depending on the turn.

 

Not that I've used any that weren't in normal everday inexpensive cars but my favorite so far is definetly audi/vw's DSG (tried about 3-4 others) sadly do not own a car with one but test drives gave me a good idea as to what they were like to live with. Only had one owner complain of reliability