in fast and the furious vin dielsel says paul walker was granny shifting and not double clutching like he should, what the hell is double clutching??!!!

 

I have heard a few things about double clutching amd everyone has ther eown opion th eonly one i remember is

when you push in the clutch you give it a shot of gas then put it into gear you had to do this in old cars because the gears where not synronized and same with transport trucks but tha tis jus tone of the many I hav ebeen told

 

It's this.

In gear.
Clutch in.
Shift to N
Clutch out.
Rev RPMs to meet tranny.
Clutch in.
Shift to next gear.
Clutch out.

Completely useless in todays cars, they have synchro's now that do this for us. All you have to do is revmatch to save your tranny.

Incase you don't know. Revmatch is:

In gear.
Clutch in.
Rev RPMS to meet tranny while shifting to next gear.
Clutch out.

If you're double clutching now, you're about 3 car lengths behind.

 

Sorta like a power shift which I dont ever do!

In gear at mid RPM's
Clutch in (not too long cause your foot is still on gas)
Clutch out

It aint hard to get a dx to chirp in third at mid rpms.

 

Well, the discriptions of double clutching and rev matching, at least the processes of, are reasonably accurate but beyond that, you've off a bit.

Double clutching, done properly, matches the rotating speeds of the internal transmission parts with the speed theyll need to be for the gear your downshifting to. Doing this will take a LOT of pressure off the synchro's (especially if you're dropping more than one gear. Example: a 5th to 3rd downshift) and, depending on how you usually drive, signifcantly extend their life. Do you "have" to do it? No! But it doesn't hurt and to say that the process is "completely useless" is totally wrong.

Rev matching is simply reving the engine during a downshift so that it's rpm will match what it needs to be for the gear your downshifting to. Doing it properly will result in a smooth downshift. No lurching and bucking as the engine is forced to the proper rpm as the clutch is released. It makes it a lot more comfortable for the driver and especially any passengers in the car. It also helps to reduce the stresses imparted the the engine, clutch, transmission / transaxle, and drive shafts because they're not being jerked around by sloppy shifting techniques.

As for being 3 car lengths behind? If you're going to race someone you should be in the right gear to begin with, not frantically downshifting "after" they say "Go!"

FWIW!

Drive Safe,
Steve R.