You cannot have your cake and eat it too. Says who? In the world of motor vehicle transmissions lately, there have been several attempts at both possessing and munching one’s gateau by having the lazy convenience of a full automatic and the option of performance-enhancing, DIY gearshifts when the need arises.
This type of transmission goes by numerous labels, depending on the manufacturer: Geartronic, Touchshift, Sport-tronic, Steptronic, TAPshift, Comfortronic, CommandShift, E-Shift and so many other –tronics or –shifts, but the most common name is Tiptronic, a joint Audi/Porsche trademark.
The proper name for the automatic gearbox with manual override, which is what I am talking about, is Manumatic, a portmanteau word combining manual and automatic.
And this is how it works: The standard transmission is your typical automatic, but it is equipped with a manual function in a smaller slot or gate extending from the D position.
While in D, the transmission is fully automatic, but pushing the gear stick into the smaller slot overrides the computers, meaning the car will not shift gears without driver input.
The smaller slot has two spring-loaded positions: “+” for changing up and “-” for changing down. The exact layout, again, depends on the manufacturer, because cars like the Mitsubishi Galant have the function working up and down, while Mercedes have theirs working left and right. When the gear lever is tapped into the + or -, it springs back into its original position.
How to drive the manumatic: Seeing how the manumatic starts life as an automatic, cars equipped with this trick transmission are driven like automatics.
If curiosity, or haste, gets the better of you and you resort to the “Tiptronic” function, this is what to do: Slide the selector lever into the Tiptronic/Steptronic slot, right where the “+” and “-” graphics are.
The transmission will stay in whatever gear it was in while automatic and it is from here that you will start shifting up or down. The rest is a PlayStation-style approach: push the lever towards the “+” to change up (2-3-4…) or towards the “-” to change down (4-3-2…).
Performance specialists like Mitsubishi’s Evo X, or the world-famous Bugatti Veyron, have paddle-shift Tiptronic transmissions (and DSG), which have a supplementary kit for even faster and more convenient shifting.
These are a pair of paddles mounted on the steering column just behind the wheel. One shifts up (+), and the other down (-).
Lexus’ RX330/ Toyota Harriers also have this layout, giving the driver the option of not taking his hands off the wheel even when going through the gears without electronic intervention.
Porsche’s Cayenne, a horribly expensive car, has buttons on the steering boss cross-member, four of them; two at the 3 o’clock and two at the 9 o’clock positions.
The upper button shifts up and the lower one down, on both sides. (We know, it can be a bit disorienting).
The joy of this transmission is that the switch between manual and auto occurs at any speed, you do not have to stop or go through some ritual to change over.
A reader was concerned that switching from auto to manual will cause the gearbox to default into first, and what if this happens at 150 km/h? Not a chance. When changing over to Tiptronic, all you are doing is telling the computer “I will take over from here, if you don’t mind”.
The only instances when the auto function cuts into the manual is when the revs dip to below tick-over (what you call idling) causing the transmission to downshift automatically to prevent the engine from stalling, or when redlining, really mashing the firewall, which causes the ‘box to upshift by itself to prevent over-revs or engine damage.
The boring stuff: The manumatic, like other typical automatic transmissions, uses a fluid clutch — the torque converter — rather than an electronically operated friction clutch.
The gearbox itself is governed automatically in D, but when the lever is pushed to the side, into the manumatic function, this is what happens.
Bumping the lever up/down or left/right shifts gears. What these little taps to the gear-stick do is rotate a notched wheel, a simple cog, which is meshed to a ratcheting drum.
The drum has grooves cut into its side, and it is these grooves that either move the gear selector forks directly if the drum is mounted next to the gears, or manipulate standard control rods which then manoeuvre the selector forks if the drum is mounted away from the gears.
The former setup is preferred because it is less complex and needs fewer parts. The selector forks are within the gearbox itself, and as their name suggests, they select the gears.
Moving the gear lever once causes the ratcheting drum to rotate through a certain degree, say 60, equivalent to one gearshift up or down.
The drum, in turn, moves the selector forks/rods in such a way as to select the next gear up or down.
Because of the drum, the gears are sequential and it is impossible to skip gears or miss a shift — a common occurrence during high-speed driving with fully manual transmissions.
Pros and cons: Obviously, manumatic transmissions offer a good compromise between fully manual and fully automatic powertrains. In “manual” mode, the shift speeds are quicker compared to conventional manuals.
Imagine the change from 2nd to 3rd: with an H-type manual, you push the lever up, over to the right and up again, clutching and declutching in the process, but with a manumatic you simply tap the lever.
Downshifts are easier and less painful for those who cannot double-declutch or rev-match by heel and toe. Balancing the clutch is also not an issue.
Consistency is another advantage, eliminating the need to think or rack your brains trying to remember if you were in 3rd or 4th.
The shifts are all the same: tap this way to shift up, the other way to shift down. In a manual, you will need to keep in mind what gear you were in to execute a flawless upshift or downshift (5th to 4th — pull down, move left and pull down again… no, wait! I AM in 4th already. Oh shoot).
The lever position in a manumatic is always the same irrespective of the gear you are in, unlike a manual where 1st and 5th are polar opposites location-wise. You do not need a darts champion’s skill to locate the gear positions.
One last advantage over a conventional manual is as mentioned above: it is impossible to miss a shift. No gear skipping going up or down, which in turn leads to a silky, flawless drive.
The manumatic’s advantage over a full automatic is simply the manual facility. This helps prevent hunting, the tendency of automatics to keep shuffling between two gears searching for the right ratio.
In keeping with the torque coming from the engine and the load.
In hard driving, the manumatic also allows for short-shifting, where the driver changes up before the optimum engine revs in anticipation of circumstances ahead.
Short-shifting applies mostly in circuit racing where a series of switchbacks beckons and there are no straights in between to change gear in.
This brings us to the next advantage, that of holding onto a gear through a long corner.
In performance driving, changing gear mid-corner will cause a drift, and that is one of many reasons why nobody races in a fully automatic car.
But it is not all cake and flowers for manumatics.
Some have in-built characteristics that are, frankly, annoying. One is the tendency to default to the fully automatic setting if no manual input is made after eight seconds.
This is a feature of Porsche’s Tiptronic S system, as seen in the Boxster Cabriolet and Cayenne SUV. Audi’s 5-speed tiptronic will only allow you to play with gears 3, 4 and 5; 1st and 2nd are always engaged for you.
At the end of the day, the manumatic still does not feel like a manual, and it is ultimately slightly less engaging, but that is just nit-picking. It also does not let you control clutch engagement, and it will cost you a tidy sum over a similar car with a manual tranny.