I'm not sure why you quoted me as I was in agreement with rev matching and double clutching being 2 different things. Anyway, more info for readers who are actually confused about this subject.

 

[QUOTE=tabach0y273,Apr 23 2005, 02:45 PM] I'm not sure why you quoted me as I was in agreement with rev matching and double clutching being 2 different things.

 

The "wasted motion" of letting the clutch out in neutral is actually a critical aspect of double clutching. When you let the clutch out, the gears inside the transmission are connected to the engine, even if you are in neutral. When you blip the throttle to rev match (with the clutch out in neutral), the gear you want to shift into spins at the same speed as the collar connected to the drive shaft (i.e. the thing that connects to a gear to put you "in gear"). When the gear and the collar are spinning at the same speed, it is easy to shift into that gear.

It is generally not necessary to double clutch, because modern transmissions have synchros. However, I still find it useful when downshifting into first when going 10 mph or more.

 

copied from.....http://www.felixwong.com/openroad/double_clutch.html

One of the joys and delights of a true sports car is the manual transmission. In addition to allowing the driver to be in control of the gear-selection process, manual transmissions generally provide superior fuel economy and performance than automatic transmissions. It is essential, however, to know the "proper" way to shift a manual transmission to enjoy these advantages while enhancing driver/passenger comfort.

Virtually everyone knows how to upshift a "stick", but downshifting is an art that few Americans seem to know how to do well. In particular, very few drivers today double-clutch (or "double de-clutch"), which is also known as "matching revs" between the engine and transmission. Most drivers, when downshifting, merely press in the clutch after letting off the throttle, jam the stick in a lower gear, and then let out the clutch. In modern vehicles, this is possible with synchromesh transmissions, but is usually accompanied by a sudden rearward weight transfer, if not any less-than-harmonious engine/transmission noises. To the occupants, especially the passenger, this jerkiness can be annoying, and in spirited driving, this sudden weight transfer can have an adverse effect on handling. Perhaps more importantly, however, is that the life-span of the synchromeshes may be shortened with this practice. The solution, then, is to double-clutch!

To double-clutch during a downshift, perform the following steps:


Let off the throttle, press in the clutch, and shift the "stick" to neutral.
Let out the clutch.
Bump the throttle to make the engine "blip". Sometimes in my MG I'll press in the accelerator all the way to the floor for a fraction of a second.
Press in the clutch.
As the engine speed decreases to match the transmission speed, throw the stick into the next lower gear. Since you actively "matched the revs", it should fall right in!
Let out the clutch. The downshift should have been as smooth as butter!

Note that Steps 1-6 are actually performed in a split-second. To start double clutching for the first time, you may perform the steps slowly. However, with practice, everything becomes second-nature. In addition to saving wear-and-tear on the transmission, double-clutching sounds cool (due to the throttle-blip) and shows the passenger that you are an "adept driver".

 

back to the initial post...

i heel toe before coming to a stop, and the shifter just slips into first like...it was meant to be there.

 

And after some practice it becomes second nature.

 

If you shift properly from 2nd down into 1st, it goes in smoothly. I use a downshift into 1st for a particular corner I hit on my daily commute.. allows me to get into the VTEC range quickly.

 

Not to be a jerk or anything, but just because Felix Wong says something doesn't make it true.

Double clutching often involves rev matching, but you can rev match without double clutching.

 

P.S. Lots of good info here:

http://auto.howstuffworks.com/transmission3.htm

 

Letting the clutch out while in neutral does do something, though on most modern cars it doesn't matter that much.

There are basically three rotating shafts that we need to worry about: crankshaft, mainshaft, and output shaft. The crankshaft is part of the engine and extends back to the clutch. The transmission mainshaft extends from the clutch into the transmission, where it has gears on it. Then there's the transmission output shaft, which has gears on it that match up to the gears on the mainshaft, and transmits power on back toward the wheels.

The process you're talking about, without double clutching, does this:

- depress clutch to disengage crankshaft from mainshaft

- move shifter to neutral to disengage the mainshaft from the output shaft

- rev the engine to get the crankshaft to the correct speed for the new gear

- move shifter to new gear to reengage the mainshaft to the output shaft at a different gear ratio. The synchros take care of accelerating or decelerating the mainshaft to the correct speed for the new gear ratio

- finally, release the clutch to reengage the crankshaft to the mainshaft. Both of these are already rotating at the correct speed for the new gear, the crank because we rev matched, and the mainshaft because the synchros did their work.

Double clutching adds a couple of steps, letting the clutch do some of the work that would otherwise be done by the synchros:

- depress clutch to disengage crankshaft from mainshaft

- move shifter to neutral to disengage the mainshaft from the output shaft

- rev the engine to get the crankshaft to the correct speed for the new gear

- release the clutch pedal, bringing the mainshaft up to speed for the new gear (added step)

- depress clutch, again disengaging the crankshaft from the mainshaft (added step)

- move shifter to new gear to reengage the mainshaft to the output shaft at the new gear ratio. Synchros don't have to do any work because the mainshaft is already at the correct speed for the new gear

- finally, release the clutch to reengage the crankshaft to the mainshaft, which, again, are already rotating at the same speed.