i was just wondering i saw someone in an S4 w/ a stage III, and people said he was double clutching....what's this mean...i learned at one point (when F&F movie came out) but must've forgotten...

 

That's necessary to do with a manual tranny that has no (or very weak) synchros. 1) Step on the clutch to put it in neutral; 2) match engine speed to car speed for next gear; 3) step on clutch and shift to chosen gear.

I learned it on a 66 MGB without 1st gear synchros and broken 2nd gear ones.

BTW, it is totally unnecessary on a modern tranny with proper synchros. You're also using the throw out bearing twice as much while marginally extending the life of your synchros. Of course, they should last the life of the car if you don't "speedshift": shift w'out benefit of clutch... ouch.

 

i'm still kinda confused....i see it two different ways, and am not too familiar with Manual cars (having never owned one)...

1. do you mean pressing the clutch and accelerator at the same time while in neutral ?
or...
2. matching the RPM's to the engine speed while in neutral???

 

He forgot to explicitly state a couple steps.. such as actually letting go of the clutch again ... details, details... but

1. Disengage clutch
2. Shift into neutral
3. Engage clutch
4. Push accel to rev engine to match speed for next gear
5. Disengage clutch
6. Shift into next gear
7. Engage clutch

no grinding noise = good!

 

All of this done quickly while downshifting and braking at the same time (known as "heel and toeing"). Ball of your right foot is on the brake and you rock it onto the accelerator to blip the motor while passing through neutral to match engine rpms to drive train rpms.

Its primarily a road racing technique for enhanced stopping, vechicle stability and being in the correct gear to accelerate out of a corner. Saves a bunch of wear and tear instead of just dragging the car down on the clutch.

Unless you have a British car of course. Then you double clutch up and down to keep from turing the gear box into mush.