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Discussion Starter #1
Granny Shifting

When we first learn about the mysteries of the manual transmission and that third little pedal on the left we all heard something like this- “Ok-wiggle the stick and make sure it is in neutral, gently push in the clutch all the way, carefully push the stick into first gear and slowly release the clutch and give it a little gas.” This would result in one of two outcomes- a hard lurch and stall or almost no perceptible forward motion and the sweet odor of burning clutch accompanied by shouts of “Let it out! Let it out!” Once the car actually moved in first you would repeat the process for each successive gear shifting as high as 3000 rpm and letting off the gas between shifts. With practice you could do this smoothly and even quickly, conjuring visions of Dan Gurney blasting down the Mulsanne straight.

Today, we politely call this process Granny shifting- guaranteed to prolong the life of both transmission and clutch and not raise any eyebrows with your local patrol officers.

Speed Shifting

If you are reading this then you assuredly moved on to the next stage, which we call Speed Shifting. Once you had a taste of a couple of stoplight acceleration contests you realized that the time spent between shifts was wasted, especially if you went up against an automatic, or worse, an auto with a shift kit. With each shift your opponent would gain a small advantage. With practice, you can click off really quick speed shifts by slightly lifting off the throttle with your right foot at the same time you stab the clutch with your left foot and slam the stick into the next gear with you right hand (or left, for those Down-Under and other such exotic places.) Now there is very little loss of acceleration between shifts and you can hang with your buddy’s automatic.

Spending some time at the track helps to refine the technique and prepares you for the final stage in shifting evolution- Power Shifting!


Power Shifting

Ever listen a manual car down the race track? You can tell the good drivers from the not so good simply by the sound of the engine at each shift.

The Granny Shifters sound like this- Waaaaaaaaa! -moment of silence- Wuh, Waaaaaaaaa!

The good Speed Shifters sound like this- Waaaaaaa !-tiny delay- Waaaaaaaa! With less rpm drop the engine does not bog down going into the next gear- you might even hear a good Bark! from the rear tires.

The Power Shifters sound like this Waaaaaaa! WHAA! Waaaaaaa! WHAA! Waaaaaa! WHAA! Waaaaa! and bark the tires in all gears (unless on slicks.) The rpms not only don’t drop- they actually go up between shifts since the throttle is wide open the whole time!

How to Powershift

The Power Shift Shuffle goes something like this- the gas pedal goes to the floor and stays there- never lift! Preload the stick by pulling on it before you reach your shift point. At the pivotal moment simultaneously KICK the clutch pedal and slam the stick into the next gear. Time it right and you will see the rpms climb 200 to 500 rpm between gears and feel a strong surge as the next gear engages.




Powershifting: keep the accelator pedal planted, and stab the clutch while throwing the stick in gear. Refresh your browser to watch it in action!
 

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In the LeMans series, the driver of the Olive Garden 575M never used the clutch, but his teammate used the clutch only on upshifts. It was funny looking at the pedal box camera view and seeing the clutch never used while his hands were chaning gears, lol. Something I'll never try in my Z...

Thanks for the tips though. I actually upshifted yesterday while getting off the throttle a little (maybe 25%). The first time the RPMs stayed the same between shifts, but the second time I tried it, the RPMs went up a bit.
 

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LMAO! I love the 'sound effects.' I think I'm going to try for those sounds and record them...

BTW, good topic. I do all three depending on my mood that day. I use granny shifting out of courtesy for my passengers. I mostly speed shift.
 

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Good little tutorial there. I basically speed shift most of the time, but at the track definately powershift. It does help a lot.
 

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:lmfao:

I've seen that civic reality before. Me and my friend imitate it all the time whenever we see a civic on the street
 

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Don't forget "double-clutching" for downshifts.
 

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Discussion Starter #13
Double clutching originated a while back when cars didnt have synchros. It just gave the motor time to drop its speed to match with the gearbox. Today since we have sychros, all we have to do is "blip" the throttle. :wink:
 

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Discussion Starter #14
But since you mentioned it , here's an article about it..

he following is a beginner's approach to learning how to double - clutch. This technique allows downshifts from higher speeds without any synchroniser wear. This is VERY important if you ever want to drive really quickly and keep your transmission intact for extended periods!



The Easy Way to Double-Clutch
By Jeff Krause.


Double-clutching is the proper way to downshift at speed without placing excessive wear on the transmission's synchronizers. This allows you to select a much lower gear without the tell-tale lurch you normally get when the clutch is let out after downshifting.

When downshifting from 4th gear to 2nd at 50 mph, I need to raise the engine speed from 2200 rpm to 5000. To prevent excessive synchroniser wear, the clutch is depressed and the shifter is moved to neutral. The clutch is then released, and the gas is depressed to bring the engine speed up to where it needs to be for the lower gear. The clutch is then depressed again and the shift lever moved into the lower gear. When the clutch is released the second time, the engine is already turning the proper speed . While this sounds complicated, it's easier done than said, and only takes about a second.

To better understand how the process works, a little background on transmission fundamentals will help.

A typical transmisson has two shafts, one connected to the engine through the clutch, and one connected to the rear wheels. There are usually four to six sets of gears on these shafts and they are selected with the gearshift lever inside the car. When changing gears, the clutch is depressed to disconnect the engine from the transmission so there isn't any stress on the moving parts. Since the output shaft is permanently connected to the rear wheels, the only way to match the speed of the two shafts is to use the throttle to adjust engine speed.

Once the engine is turning the right rpm, both shafts will be turning the same speed, and the gear lever will fall into gear WITHOUT using the clutch! (Although most of the time you are shifting too fast to be that accurate)
 

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25 years of driving big trucks (that don't have any synchros) taught me: the key to shifting smoothly is rpm's. I can shift anyting without using a clutch - if the rpm's match up. Period.

Powershifting? Let's use your car!

If you want to drag race, get an auto. You think John Force uses a clutch? :shiftdrive:
 

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Good powershifters dont jump revs during shifts, only $hitty ones do. ANybody that has ever seen any of my racing vids on the other Z forums or drag vids can vouch for that....
 

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I mastered power shifting in my 83 Supra when I was 16 years old. Alberto is right. If you are doing it really fast (I can) then the increase in revs won't be noticeable enough to hear. You are only between gears for 0.07 seconds.

Also, sometimes I would just put my left toe on the corner of the clutch pedal and push down at an angle, so my foot would just slip off the side to re-engage the clutch. This does make the timing a bit more tricky, and IF YOU MISS (which I have), it sounds absolutely terrible. The engine bouncing off the rev limiter while gears are grinding is not a good combination.

Done correctly it does wear out your car. But, then again, so does drag racing period.
 
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