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Hi fellow gear-heads... very cool engine graphics! On a related note, I wanted to add that, if you are not familiar with dual-clutch transmissions [1], they ar
by Arjuna 13y ago
Hi fellow gear-heads... very cool engine graphics!
On a related note, I wanted to add that, if you are not familiar with dual-clutch transmissions [1], they are pretty interesting.
One example (many manufacturers offer this type of transmission) is the Porsche Doppelkupplungsgetriebe (or simply PDK) [2], developed by Porsche. It is essentially two gearboxes in one complete transmission package, where both gearboxes possess their own clutch. When a gear is selected in one gearbox, the next gear is pre-selected in the other gearbox. The result is a nearly-instantaneous gear change, with smooth power delivery.
[1] https://en.wikipedia.org/wiki/Dual-clutch_transmission https://en.wikipedia.org/wiki/Dual-clutch_transmission
[2] https://www.youtube.com/watch?v=C7Zh-nQPh_8&t=33 https://www.youtube.com/watch?v=C7Zh-nQPh_8&t=33
- chiph 13y agoThe new Corvette does something interesting - there's a sensor on the manual gear shift lever that predicts what gear you're going to select, and will do the rev matching for you. Result is a perfect downshift, every time.
- kirse 13y agoYep, Nissan's 370Z has had SynchroRevMatch as part of its Sport/NISMO packages for a few years now, and from what I've heard through friends it's very simple and works really well... Although it makes me wonder at what point on the spectrum does a "manual" become an "automatic" http://en.wikipedia.org/wiki/Synchronized_down_shift_rev-matching_system http://en.wikipedia.org/wiki/Synchronized_down_shift_rev-mat...
- mercnet 13y agoSometimes I do not have the right shoes on to rev match so I can see this feature being useful. I would consider a car a manual if the user has to press a clutch in before changing gears.
- philsnow 13y agoRight... shoes? I haven't driven a stick regularly since high school, don't people rev match with their ears ?
- TomEllis 13y agoYes right shoes. If you want to heel toe, you can't do it in your steel capped boots http://www.youtube.com/watch?v=muxVLOaw2ik http://www.youtube.com/watch?v=muxVLOaw2ik
- coldpie 13y agoEh, you can revmatch without heel-toeing. I did it for years before I started driving at the track and learned how to heel-toe. You just brake enough for the turn, then let off the brake entirely and blip the throttle and drop the clutch while turning.
- grecy 13y agoThat's one of the major reasons the GT-R is so quick off the line and down the quarter mile. It was the first production car with a dual-clutch transmission that was actually realistically priced, and it's still arguably the most cost-effective.
- nexox 13y agoActually VW sold a dual clutch DSG transmission in the 2003 R32, years before the GTR hit the market, and for a fraction of the price. All other things the same, a dual clutch is not much faster than a properly-operated manually-clutched gearbox, but in the case of the GTR, we'll never be able to make that comparison.
- grecy 13y ago> a dual clutch is not much faster than a properly-operated manually-clutched gearbox That's not correct. When the GT-R first came out I read a great article about why it was so damn quick down the 1/4 compared to super cars that are 2-6x more expensive. The reasons were: 1. Most of them dyno at around 480hp AT THE WHEELS. So it's making more power than Nissan claims. 2. It's the first car to get all the electronics (stability control, etc. etc.) good enough to actually make it faster, not just get in the way 3. The dual-clutch gearbox changes were so fast, they did a comparison of how long the GT-R is in neutral during the 1/4 compared to other supercars with regular manual gearboxes. I remember the time difference being in the .4-.8 second range. That was the #1 reason it was so fast - it spends an extra 0.5 seconds actually putting power to the road, which is obviously huge in a ~12 sec 1/4.
- nexox 13y agoYou seem to have ignored my "All other things the same" qualifier - that means you have to assume that power, weight (except for the difference between the gearboxes,) suspension, environment, tires, and everything else, is identical for the quoted part of my sentence to apply. I don't see how your first two points are relevant to what I said, or your original post. You can love the GTR all you want, I don't mind, and I never claimed that there was anything wrong with it. As for point 3, if you were to compare to a theoretical manual transmission GTR, that half a second of extra power would still only net you a couple tenths advantage, since acceleration and aerodynamic drag are nonlinear. And I stand by my claim that a couple tenths on a 12 second quarter mile is 'not much faster.'
- lucb1e 13y agoMy parents' car has something like this (DSG). It takes forever between pressing the gas and actually moving forward. After that the car is fast and has power, it's just not fast to get going when you press the gas, you gotta anticipate. It's really very annoying and I much prefer a normal car, I really can't recommend it to anyone, but maybe it just takes getting used to.