When I started driving in 1982, my car had 4 gears and reverse, nowadays most cars have 5 and reverse, but my van now has 6 gears and reverse.
Will there be a time when as many as say 10 gears are available, and will it make vehilces any more efficient ??
Finally why aren't all gears in the same place, especially Reverse,(some you lift, others push down) I'm sure many minor accidents are caused by inadvertedly engaging the incorrect gear by people using several diffenrent vehicles -why can't the motoring industry standardise it
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I suspect the variation in gear patterns is partly due to the need to engineer the gearbox to fit the space available - it was probably easier when RWD was the norm and there were only four forward speeds to accommodate.
That said, I much prefer to have reverse on the opposite side of the gate to first. It makes changing direction at parking speed much more deliberate, and it's unlikely that the car will take off the wrong way if I inadvertently select one of the high forward gears. In contrast, our new Toyota Verso has a delightfully light and precise (six-speed) box, but reverse is over on the left and protected only by a very subtle dogleg. There's a beep when I select it, but it's not very loud and it's easier than I would like to find reverse instead of first.
More than six forward speeds would be very hard to manage with a conventional manual selector, so you'd need a sequential or fully automatic change. Whatever the effect on efficiency, there's a limit to the number of ratios a driver can remember and use effectively - although I seem to manage seven on the rear hub of my bike without too much trouble!
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I think the location of reverse if mostly down to preference. A lot of current 5-speed boxes (e.g. Ford and Vauxhall) are, in layout terms, identical to the 4-speed boxes they replaced, though in Ford's case the reverse gear position has moved. Moreover, the Combo I drove the other day has an right-and-down reverse whereas my Corsa has a left-and-up, both the same vintage. It all depends on what the linkage looks like inside the gearbox, rather than the location of the reverse gear.
As for gear number, I can't see speeds going above 6. Unless you start fitting overdrives, all gearboxes require the gears to be in line along a two parallel shafts in the gearbox. Now, unless you make the engine bay wider (not practical on small cars) or the engine smaller, you'll have difficulty attaching any more gears onto the end of the gearbox without jutting into the wheelarch!
The only way to do it would be to decrease the face width of the gears, and reduce the size and travel of the synchromesh units. This can be done with more precise (and expensive)engineering and better quality materials to reduce the chance of increased wear of the torque going through smaller componentry.
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I remember when the Corvette ZR-1 came out (1989?), I think that was the first car I heard about that had a 6 speed gearbox. The sixth gear was really long, geared for something like 47mph/1000rpm, in order to 'cheat' the CAFE emissions regs. That made sense in a car with massive power and torque (in its day) and that was capable of over 180mph.
But is 6 speeds necessary in an ordinary car? My car has 5 and I dont find myself wanting an extra ratio. Don't some Mercs (or is it Lexi?) now have a 7 speed automatic? I dont get the point of that?
The ZR-1 gearbox also had a system where if you tried to change from 2nd to 3rd at less than one quarter throttle, a solenoid would push the lever over and make you to select 4th. Sounds like silly intervention but perversely I always wanted to drive one and try it.
Edited by Rich 9-3 on 05/07/2008 at 15:26
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I can understand a 7 speed auto - must be really seamless but a six speed manual is a pain in arm and leg - there again I hate changing gear.
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I completely follow Wotspur's point about "standardisation" (lack of) and the confusion arising from driving different cars with different reverse gear layouts. Surely it's not beyond the wit of gearbox/car designers to fit as absolutely standard a lift-up-collar for reverse ?!? And the earlier post about the Verso is spot on - abysmal reverse gear position and about a foot of travel on the handbrake. There is a Ford catalogue option for my new Focus of an illuminated gearknob, which says it all.
Last month I had to drive five different cars in as many days and I was driven insane by the idiosyncrasies of conventional/electronic/"automatic" parking brakes and reverse gear layouts and had "hours of fun" with party games I loved as a child but hate as a driver: Hide and seek with front and rear wash/wipe controls, blind man's buff with headlight and foglight switches and finally pin the tail on the hot/cold air control for the aircon/climatronic.
It can't be long before some bright spark in a design studio decides to play around with the pedal layouts and maybe fit a "Knight Rider"-type rudder to replace the century-old fully standardised wheel we all know and love.
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I could never understand why people wanted automatics with a macho T-bar and gate on the transmission hump, when a more delicate lever behind the wheel, if properly designed, is obviously better in every way (as is an indicator in the driver's line of sight or near it, not down on the floor in that moronic way). The DS's delicate gear switch was delightful, although you had to get used to the rhythms of the gearbox, rather slow.
I like gearchanges with an exposed gate, and I liked very much the r/h remote gearchange that Royce cribbed from Hispano-Suiza along with the mechanically-operated brake servo, and that was fitted to most Rolls-Royces from the twenties to the fifties.
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