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| tom66:
--- Quote from: james_s on March 09, 2023, 06:18:42 pm --- --- Quote from: tom66 on March 09, 2023, 08:27:05 am ---Nope, it's a dual clutch transmission. Think of it a bit like two manual gearboxes bolted together with an electronically actuated clutch on each to select the relevant gear. In general the arrangement is one shaft has R, 2, 4, 6 and the other has 1, 3, 5 and maybe 7. The gearbox computer preselects the next gear when you are accelerating. For instance in gear 3, the actuators have selected 4 on the 1st shaft, so all that happens when it changes gear is the next clutch actuates instead. This also works for downshifting. You might be cruising in 6th (top gear on my car), in which case 3rd is preloaded on the alternate shaft, and if you gun the go pedal it will jump straight to 3rd. The DCT can shift faster than even a trained manual driver and on the hybrid models the gear RPM matching is done with the electric motor to further speed up the change. I can't see why you'd want to slip the clutch in snow and ice. If you need less torque you can force the car into 2 or 3 and then just press the go pedal less. I found electric only operation to have the best performance here as the traction control can modulate the torque more quickly and over a wider range. Obviously not all vehicles have that but the car can modulate the clutches just like any other manual, it does that when you're parking at low speeds if the engine is running. --- End quote --- Yes I'm familiar with the DSG, I've driven a VW that had one. Most of the manually shifted automatics I've driven have been of the conventional type or worse, a CVT. At least the DSG is nice and crisp. I suspect you've never driven a manual in snow and ice or it would be very obvious why I'd want one. One specific trick I've used quite a few times is when I find myself unable to get over a hump like the snow that has built up in front of my stopped car, or the hump of a curb to get into a driveway is to ride and pulse the clutch such that the car rocks forward and back, the rocking motion gets larger and larger until there is enough movement to crest the hump and then you're off, I'm not aware of any way to do this in an automatic. Another big advantage is in a situation where engine braking causes the wheels to slip and slide, if you push in the clutch the drivetrain is instantly disconnected and the car will straighten right out. This works on wet roads too if the rear end starts to slide out, at least on RWD cars. I've driven everything, manual, automatic, automatic with lockup torque converter, DSG, CVT, RWD, FWD, AWD, gasoline, diesel, hybrid, several EVs, and everything from subcompact to large commercial trucks, antique to modern and for all of the ICE options the plain manual is far superior to me. --- End quote --- I've driven both a manual car and this car in snow of similar severity. I would take the DSG hybrid every day of the week in those conditions. It is far easier to modulate power at low speeds with the electric motor but even using the engine you just press the accelerator slightly and it will ride the clutch for some time. Unlike a manual though it will eventually move you off the bite point (eventually goes neutral) if you are there for more than about 20-30s. This is to prevent the clutches from overheating. But I guess you can burn the clutch in a manual if you wanted to. The larger clutch plate probably gives it a bit more endurance in comparison, though the clutches in most DSG's are wet oil type. I assume the oil gives them better endurance but I don't know for sure. As for coasting, shifting into neutral or being in drive with the go pedal off achieves that function. In ice I put my car in 'drive' instead of 'regen' which means it coasts when the pedal is released rather than brakes, reducing the chance of a slip. Ultimately though I've never had too much issue with decent tyres and plenty of braking distance. Snow tyres make a huge difference in terms of grip, more so than any choice of gearbox. In my FWD car with these on I found myself climbing snowy hills with ease despite several 4x4's with presumably all-season tyres being stuck at the bottom. |
| AndyC_772:
I miss my Subaru P1 with winter tyres. Manual gearbox, grabby clutch, big turbo. It took some skill to drive in snow and ice for sure, but that's completely OK. It never once got stuck. |
| coppice:
--- Quote from: tom66 on March 10, 2023, 09:20:20 am ---I've driven both a manual car and this car in snow of similar severity. I would take the DSG hybrid every day of the week in those conditions. It is far easier to modulate power at low speeds with the electric motor but even using the engine you just press the accelerator slightly and it will ride the clutch for some time. Unlike a manual though it will eventually move you off the bite point (eventually goes neutral) if you are there for more than about 20-30s. This is to prevent the clutches from overheating. But I guess you can burn the clutch in a manual if you wanted to. The larger clutch plate probably gives it a bit more endurance in comparison, though the clutches in most DSG's are wet oil type. I assume the oil gives them better endurance but I don't know for sure. As for coasting, shifting into neutral or being in drive with the go pedal off achieves that function. In ice I put my car in 'drive' instead of 'regen' which means it coasts when the pedal is released rather than brakes, reducing the chance of a slip. Ultimately though I've never had too much issue with decent tyres and plenty of braking distance. Snow tyres make a huge difference in terms of grip, more so than any choice of gearbox. In my FWD car with these on I found myself climbing snowy hills with ease despite several 4x4's with presumably all-season tyres being stuck at the bottom. --- End quote --- Its really hard to compare what you used to find in one car with what you find today in another. They keep refining traction control, chassis stability control, torque vectoring, ABS, and so on. That whole package can make a huge difference to performance in poor weather. |
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