no, that's just rev matching WHILE double shifting

double shifting is what it sounds...you push the clutch twice

once to go in neutral, and again to shift to a lower gear after you have slowed down while in neutral (when you switch to a lower gear, you have the option of rev matching, but the act of rev matching is not what makes it a double clutch)

instead of going from 4th to 3rd, which is a regular downshift, you go from 4th to neutral to 3rd (again, rev matching as you please)

 

Uhh I thought double clutching is when you do a complete down shift, depress clutch and rev then let clutch go. IS that correcT?

 

no, that's rev matching...you rev match when yuo downshift

power shifting is you shift gears at wide open throttle without letting off the gas pedal at all


HEAL-TOE shifting is being able to downshift while braking at the same time (all in a simultaneous and quick action)...it's very hard to do and you need a lot of practice

picture yourself downshifting as you approach a turn, but you want to brake at the same time.....you can't do it unless you (a) have 3 feet, or (b) use heal-toe method

with your right foot blipping the throttle to rev match, your left foot turned to the left and left heal begins to depress the brake, while in that same motion your left toes depress the clutch....so at the same time you're pushing the clutch, braking, and blipping the throttle to rev match

 

precisely as i thought. the fluttering allows a smooth entrance into the lower gear.

it is actually very useful if you are looking to conserve your clutch and don't mind using your brakes that much more.

it's something i like to keep in mind right now because i'd rather spend $400 on some new brakes than a grand on a new clutch.

i don't track yet, so it's not a waste of time. this is actually ideal for me. i also enjoy the smoothness of acceleration when dropping down a gear while using this method.

 

ah... very good.

 

i think you're trying to say the same thing as me, but wording it differently

double clutch/shifting:
4th gear
clutch
neutral
let off clutch
brake
clutch
3rd gear

regular downshift:
4th gear
clutch
3rd gear

 

whoa i'm confusing myself now haha

 

You guys are right, double clutch shifting is used when down shifting. The idea is to be able to allow your engine and transmission to catch up to the speed of the wheels.

The modern transmissions have almost eliminated the need of the double clutch technique when downshifting due to the syncros, but there is still an art to the rev matching.

When down shifting, let's say from 4th to 3rd, if you were to just depress the clutch, shift to 3rd and release the clutch, the engine speed would have to catch up to wheel speed due to the lower gearing. This will cause the car to decelerate and put an unnecessary load on the engine and transmission. Double clutching can eliminate this.

(the following 2 examples assume that you are not trying to decelerate, just trying to down shift...)

Here's how it goes...

1. While in 4th, push in the clutch and shift to neutral, then release the clutch.
2. While in neutral tap the accelerator to raise the engine and transmission rpms.
3. Then push in the clutch, shift to 3rd and release.

Sounds easy enough, however, this needs to all happen in a fraction of a second so the engine rpms don't fall off again. It takes a lot of practice to get the sequence down and also to figure out how much gas to give to match the wheels.

HOWEVER...

Like was said earlier in this thread, the modern syncros have eliminated the need to match the transmission rpms to the wheels so all you have to worry about is the engine. This means the double clutch technique is not required so the process is easier. The rev matching still needs to occur for the motor but there is no need for the shift to neutral and release of the clutch.

It would go more like this.

1. While in 4th, push in the clutch.
2. While shifting to 3rd and with the cutch still depressed, tap the accelerator.
3. Release the clutch.

Done right, either of these techniques will allow for seemless downshifting.

Performing these techniques while braking is another story. That will require a little heal-toe action between the brake and the accelerator.

 

heel-toe'ing isnt hard at all.

dont try working the clutch and brake with the same foot, at least when theres stuff around you to run into or run into you. the brake and gas are modulated with the same foot, and the other foot works the clutch.

 

:doh:

i knew i had something wrong...all this typing and thinking got me confused this late at night, haaha

i'm too uncoordinated

 

downshifting like this is using the engine to help braking, but its mostly so youre already in the right gear coming into the turn, letting you power out of it. this isnt saving your clutch any unless you were dragging it out to slow you down, which is a horrible habit no matter what.

 

yea, i tend to drag a bit when i don't double clutch.

 

I agree with double clutching is not needed anymore, but at least the mad scientist doesnt need to rip apart my block, and fix the piston rings i fried *OHHHH's in the backgroud*

Side note: its sad, but i bet everyone knows at least one line from that movie (shutter)

 

I ordered my full Motec exhaust yesterday.

 

anyone shift gears to neutral without push in the clutch ? ex; 3rd gear to neutral.
i do this all the time...is there side affect?