In any given quarter mile there is nearly a second of just sitting there coasting. On the average road course, maybe 2 or 3 seconds per lap of utterly failing to accelerate. In something like the Dakar rally, it could possibly be an entire week that's wasted.
That time, of course, is spent standing on the clutch and stirring the stick. Shifting gears the normal way is a colossal waste of time. A blazingly fast shift takes about a quarter of a second. Make eight upshifts per lap and you just blew 2 seconds. Do 30 laps and that's a minute of coasting that could have been spent accelerating.
Imagine this instead: You launch in first gear just like any other car (with a cloud of tire smoke and a dent in the firewall, of course), but when you get to redline, instead of jabbing the clutch and grabbing second, you keep your right foot planted, do absolutely nothing with your left, and slide the shifter into second gear. And with nothing but a clunk and a surge, you're in second gear. No lifting, no grinding, no break in the sweet thrust of acceleration.
That's pretty much possible now with the VW/Audi/Getrag DSG (Direct Shift Gearbox), only you push a button instead of actually touching a shifter. I explained how the revolutionary DSG works in "Technobabble" back in April 2004 and predicted that someday it would replace both the conventional manual and the dreaded slushbox.
Before DSG even gets its chance, the considerably less revolutionary (and therefore much cheaper to build) Zeroshift gearbox is gonna kick its complicated, dual-clutched ass back to Germany. Auf weidersehen.
The Zeroshift gearbox, being developed by a British startup company of the same name, is a shockingly simple modification of a good, old-fashioned dog box. Shockingly simple, that is, if you already know how a dog box works.
Here's how a dog box works:Say you've got your input shaft connected to the engine, and on that shaft you have two gears, first and second. Both gears ride on bearings around the input shaft, though, so as the input shaft spins, the gears don't necessarily spin at the same speed, or even at all.
Each of these gears has teeth around the outside (imagine that!) and three arc-shaped warts (called dogs) on the sides of the gear. (Really you can have as many as six or seven, but let's work with three.) Between those two gears sits the dog ring.
The dog ring has three arc-shaped slots on each side that match the dogs. There's just enough room between the gears that the dog ring can slide back and forth to engage the dogs of either gear or sit in the middle and not touch anything.
This matters because the dog ring is attached to the input shaft via splines, so the dog ring always spins with the input shaft. Slide the dog ring into the slots on first gear and first gear will be driven by the input shaft. Slide it into second, and suddenly second gear is the one being driven.
There are a lot of important details about dog boxes that I won't bother to explain, but here are two that matter. First, the slots in the dog ring are much larger than the dogs themselves, so the dogs can fall into the slots even when they're going at a substantially different speed. When they do fall in, they'll slap into the end of the slot with a big clunk, but they'll go in.