I do 4th to 2nd occasionally. But I always rev match or heel-toe.

 

It's just more fun rowing through gears.

 

Never skip gear, and always rev-match (even in daily driving). Shifting is fun anyway!!!

Or if I must skip gears, I usually double clutch ...

 

+1

Just to clarify.

I usually row the gears.

If I'm driving casually, I will double de-clutch. For example, sometimes I'm in fourth slowing to a red light that's about to turn green, I go from 4th to 2nd with a double de-clutch. Double de-clutching is the ONLY acceptable method in my book for skipping gears on a downshift.

If I'm driving hard, I 50/50 double de-clutch or rev-match depending on my entry/setup. Rev-matching means I'm downshifting and blipping the throttle with the clutch in. Rev-matching REQUIRES rowing the gears as the synchros were not designed for the heavy hits of taking the giant difference in rotation speeds from skipping gear. Rev-matching does nothing for the synchros; all it does is match engine to transmission for a smooth clutch out.

Rev-matching is not the same as a double de-clutch. The "feel" is the same when you clutch out, but the way the transmission internals move are different.

 

Howcome when double clutching you need to clutch out in neutral? Can't you just go from 4th, clutch out, rev, then go in gear? What is the pause and clutch in for neutral necessary for? (Sorry for the noob questions, I'm preparing for the track and just want to get things straightened out)

 

It's not.

It used to be necessary, long ago in a galaxy far, far away.

 

This is my general mechanical understanding of a transmissions.

When you clutch in (pushing the pedal down), you disengage the engine from the transmission.

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

When you clutch out in neutral, you reconnect the layshaft of the transmission to the engine. Thus with a double de-clutch, when you blip the throttle, you also increase the rotational speed of the layshaft. This is what matches you up to the rotational speed of the spline shaft from the wheel speed. In this way, you match the speeds of the two shafts to minimize the amount the synchro has to speed up or slow down anything.

Clutch in -> neutral -> clutch out -> blip -> clutch in -> shift = double de-clutch and shaft speeds match so synchros don't take load.

In a rev-match, you merely disconnect the engine from the transmissions. The shafts in the transmission are not matched in speed when you skip gears. Thus, the synchros take the load of speeding up the layshaft when you downshift. Blipping the throttle matches engine speed to the now faster spinning layshaft, but the synchros did the work. This is all fine as that's what the synchros are designed to do. However, you have to row as the synchros were not designed to take the larger differences in rotational speed from skipping gears.

Clutch in -> shift and blip -> clutch out = rev-match and synchros did the work

 

I rev match every downshift as I think its ideal for each shift to be as smooth as possible. Skipping a gear isn't necessarily a bad thing, just make sure you rev match and make sure you have enough RPMs to go to the lower gear. If you don't you're going to be looking at big time over-rev and maybe a dead engine.

 

do not skip shift

 

fixed