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Old 19th March 2004, 10:47   #16
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Double declutching sounds great on a Ferrari, actually the F1 box blips the engine when doing a downchange !
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Old 19th March 2004, 11:51   #17
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Hey Ajmat,

I dont have any official information on this issue, but i dont think that the Ferrari F1 tranny double clutches.

It does blip the throttle, but that is because it is rev-matching, and does not DOUBLE clutch in the process, which overall takes around 200miliseconds.....so thats another reason i dont think its double clutching....

Infact, the engine management is so precise that a lot of the time the rev-matching is so perfect that there is no need to even clutch a single time!! (hence ~200milisec shifts)

Thats my opinion, and if you do have info stating that it does double clutch i would be interested to read abt it.
cya
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Old 20th March 2004, 07:46   #18
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Hey,

Just though i'd also clarify that when "double clutch" is said (as a noun) it refers to a mechanical system similar to what RG has posted here>
http://www.team-bhp.com/cgi-bin....7;t=348

Otherwise everything we have discussed here is about "double-clutch" the verb! ie. to double-clutch

cheers
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Old 29th April 2004, 14:56   #19
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WRC cars make 2 noises
1. whine of the turbo - when accelerating
2. blow-off valve - when u take foot off accelerator. this is basically the excess air that is let out of a blow-off valve which is installed between the turbo and the throttle body. basically when the u take ur foot off the gas pedal, the throttle body closes, but the turbo is still spooling and creating pressure. The blow-off valve then opens and lets off this air from the intake pipe. there are a lot of diferent types of sounds u can get - from loud hisses to some really funny noises.
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Old 29th April 2004, 19:48   #20
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Quote:
Originally Posted by [b
Quote[/b] (Stratos @ Mar. 18 2004,21:59)]The new BEST buses do have a Synchromesh... there are automatics also
lol i hope they dont have "Kickdown" in the automatics
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Old 29th April 2004, 19:54   #21
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Quote:
Originally Posted by [b
Quote[/b] (ajmat @ Mar. 19 2004,18:17)]Double declutching sounds great on a Ferrari, actually the F1 box blips the engine when doing a downchange !
Ajmats. that's not double cluthing but it's similar to toe-heeling which is done to match the revs of the engine to the lower gear to make for a smoother deceleration.

While the heel blips the throttle, the toe is used to brake.

Watch any of the best motoring videos and you'll get a clear pic of it.

Regards...
Shan2nu



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Old 30th April 2004, 01:20   #22
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Well Basically 'Heel-and-Toe' and 'Double De-Clutching' go hand in hand..
And by the way, Anything said and done in Fast and Furious is not to be taken seriously, its just entertainment!
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Old 30th April 2004, 13:03   #23
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Quote:
Originally Posted by [b
Quote[/b] ]And by the way, Anything said and done in Fast and Furious is not to be taken seriously
Ya pal, did you notice that their first quarter mile took more than almost two minutes to finish?

Thats awfully slow for souped up Eclipses and RX-7s

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Old 30th April 2004, 17:53   #24
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I suppose it was a 1 Mile drag (atleast I gave them the benefit of the doubt, illegal street racers do, do 1 mile drags too)
But still Double De-Clutching is for downshifting (that to after braking for a corner or something), and why would u want to down shift in a Drag Race? That Vin Diesel's character (Dominic I guess) said it, after finishing a drag race.
Though, 'Phekum Phek' I still feel it was a very entertaining movie, full of adrenaline.



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Old 30th April 2004, 20:20   #25
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i'll tell u what i think:
double clutching is mainly to get off the line for races and drags. in case u get some wheel-spin when u take off the line u just press the clutch and release again. that gives the tyres some additional bite and u can correct ur screwed start.
i think this is double-clutching and i think i heard this from the racers themselves. i will confirm this and get back to y'all.
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Old 14th January 2005, 13:05   #26
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Thumbs up excellent article on how gears work

this article explains the fundae of double clutching and syncromesh really well

Last edited by Rehaan : 14th January 2005 at 22:09.
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Old 10th September 2005, 15:30   #27
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Double de-clutching came from the days of non syncro gears where the engine speed had to be manually mated to gearbox speed, still done today on race care with straight cut gears,clutch in, the shifter is put in neutral,clutch out, throttle blipped to come to matching revs of tranny and then clutch in again to engage the gear of your choice, racers still use it to preserve syncro life, usually used in downshifting.

I have to use it every day to save the ancient 3 speed on my Jonga which the brute HINO engine it is mated to loves to maul.

It is also a common sight in India with the trucks doing that regularly and quite well to avoid stripping the already tired syncros on their tranny.
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Old 10th September 2005, 15:52   #28
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Is it necessary on any older cars, with straight-cut gears, like the Standard Herald?
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Old 10th September 2005, 16:03   #29
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Quote:
Originally Posted by v1p3r
Is it necessary on any older cars, with straight-cut gears, like the Standard Herald?

If I recall right, only the first gear in Standard Herald had synchro, in that case, your tranny would last way longer if you were to double de-clutch, also try use a heavier oil to absorb the shock on the worn tranny, something like Elf 85W-140 GL5 which is rated safe for trannies with bronze parts.
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Old 10th September 2005, 16:11   #30
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Quote:
Originally Posted by Gurkha
If I recall right, only the first gear in Standard Herald had synchro
I'd have thought it was the other way around, like on the Premier Padmini - synchro on all gears except 1st.
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