# Double clutch



## SONET (Mar 1, 2002)

peterpan223 said:


> *So double clutch - not necessary but fun
> 
> Rev-matching - somewhat necessary and saves your syncros
> 
> ...


Actually, it's more like:

Double-clutching saves your syncros (but they should last 150K+ miles with regular use anyway) because by double-clutching you are doing their job for them.

Rev-matching saves your clutch and puts less stress on tranny/motor but doesn't help the syncros.

Be sure to read through the link that doeboy posted if you haven't already. It's a good primer. Turnfast also has a good intro on shifting (with some pictures, which can be nice), among other things.

--SONET


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## Plaz (Dec 19, 2001)

SONET said:


> * the link that doeboy posted *


It is a pretty good primer, but the very first word of the article is misspelled.


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## SONET (Mar 1, 2002)

Plaz said:


> *It is a pretty good primer, but the very first word of the article is misspelled. *


:lmao: :lmao:

--SONET


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## mwette (Sep 16, 2002)

ride365 said:


> *here's what i don't understand... why double-clutch?*


 After I recently got my new 330Ci manual I intentially broke my habit of double-clutching. I've read that syncros on trannys nowadays make double-clutch unnecessary.


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## Jspeed (Dec 23, 2001)

SONET said:


> *... Rev-matching saves your clutch and puts less stress on tranny/motor but doesn't help the syncros...*


Are you positive on that one? I swear I wore out my 2nd gear synchro on my last car by doing lots of lightning quick 1st to 2nd shifts w/o waiting for the engine rpm to drop. I imagine this to be similar to not rev-matching on downshifts.


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## HW (Dec 24, 2001)

Jspeed said:


> *Are you positive on that one? I swear I wore out my 2nd gear synchro on my last car by doing lots of lightning quick 1st to 2nd shifts w/o waiting for the engine rpm to drop. I imagine this to be similar to not rev-matching on downshifts. *


could it be the lightning quick shifting part thats doing the damage and not the w/o waiting for the engine rpm to drop?


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## Jspeed (Dec 23, 2001)

HW said:


> *could it be the lightning quick shifting part thats doing the damage and not the w/o waiting for the engine rpm to drop? *


Maybe... but I also noticed that shifting effort was lower when I waited for the rpm to drop on upshifts and rev match on downshifts.


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## ruteger (Dec 31, 2001)

If you want to _hear_ what double-clutching a car quickly sounds like, watch the movie _Bullitt_ (1968) and listen to the shifts during the famous chase scene.

Steve McQueen (or the stunt driver) double-clutches every shift in the Mustang. The driver of the Charger does not double-clutch.


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## brave1heart (Jan 7, 2002)

nate328Ci said:


> *I rev-match almost every downshift, don't double-clutch. *


Same here!


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## johnlew (Dec 25, 2001)

nate328Ci said:


> *I rev-match almost every downshift, don't double-clutch. *


I'd have a hard time rev-matching *without* double clutching.

I guess I'm old fashioned.


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