I'm sorry, I neglected to answer your question about double clutching.

Double clutching is a term, really a process, by which you match engine speed to wheel speed as an aid to shifting. many years ago, well over half a century, vehicles did not have synchonized transmissions. So in order to shift gears, the driver had to use the throttle to match the speed of the engine to that which it needed to be turning for the gear he was shifting in to. Failure to do this resulted in grinding and broken gears.

The first synchronized transmissions were only synchronized in gears above first gear. During the 50's, we saw the introduction of fully synchronized transmissions.

Synchronizers act like little clutches which match the speed of drive and driven gears so that the dog teeth of the gear sets can mesh. As you move a shifter from, say, 2nd gear to 3rd gear, what you are really doing is sliding a set of gears (really the driven 3rd gear) to meet and mesh with a drive gear.

Here is a series of short articles which describe how manual transmissions and synchronizers work.

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

 

Everyone listen to SouthernBoy, this guy is the king.

 

oh another question: Southern, when you downshift, do you actually release the clutch all the way, or do you disengage it 1/2 way, when you're blipping the throttle? I did it today based on how you described it in your long write-up, and i must say the downshifting was so smooth. Thanks for all your help!

 

Releasing it 1/2 way is enough.. TL was my first MT and i got perfect downshifting in 2 days following wat SouthenBoy posted in another thread. Your a GREAT guy man, Thanks!

Next, learn to heel and toe! plus i gotta learn wearing timmerlands cause i have to wear those for school (i go to a mechanics school) i think it makes the process alot harder >.> or am just not good enough for it

 

Anybody wanna do a heel-n-toe write up?

 

heel-toe is somewhat similar to downshifting. The thing with heel-toe is that you're braking while adding throttle.
What you do is when you're about to downshift, you apply the brake with the ball of your right foot. Then you depress the clutch (w/ the left of course), while simultaneously blipping the throttle (with the heel of your right foot, or outer part of your right foot) to match the RPMs. Then the rest is like downshift. You downshift from, say 4 --> 3, then release the clutch while adding throttle.

 

Usually when I temporarily engage the clutch as I pass through the neutral gate and blip the throttle, it is only a partial engagement. Remember, at this point, the transmission is in neutral so the amount of mass your clutch is driving is next to nothing compared with what it has to do when moving the car. In other words, there's no worry about slipping or riding the clutch.

Also, the clutch on the TL has a relatively short travel and an even shorter take-up, and on top of that, the point at which initial engagement occurs to that which there is enough clamping pressure to move the car is really short (this is one of the major reasons people have problems with the TL clutch at first).

So full engagement as you spin up the synchros is definitely not needed here.

 

Ah yes.. heel and toeing. This is something I never mastered mainly because I never had any use for it. I have always been a big drag racing fan (have done some of that in my past) and not into road racing, though I certainly respect those who do this. I once knew a buy who had set up his VW bug to autocross and he was a master at heel and toeing. AND a ride on the back roads of Fairfax County he took me on once was one of the three most terrrifying rides I've ever been on.

I can't heel and toe for the life of me, but I don't need to do this so I never worry about it. I DO suspect that the TL would be a natural for this art since its pedal placement and heighth are near perfect AND the throttle is secured at the bottom.. a super aid to heel and toeing.

 

You mentioned "timmerlands". Man you're not kidding! The type of footwear you have on will DEFINITELY affect your shifting and throttle use. I make it a habit NEVER to wear anything that keeps me from feeling the three pedals. It's not as big of a deal with my Ranger truck, but it would be a killer for me with my TL.

I would suggest to anyone learning a manual transmission to wear something like boat shoes. They have a very good feel to them and will speed up the process. Heavy sneakers or worse, boots, will make your life miserable at first with this car.

Glad you brought this up.

 

Yeah definitly, but i have no choice.. unless i keep a pair of nice sneakers in the car but thats kinda annoying.... i'll just have to deal with it.. it would feel way better if i can master it with boots on haha

 

This thred is incredible! I love the topics!

Southernboy - thanks for all the explanations, I've already noticed a difference in my daily driving. Much smoother.

And that Chevelle is an awesome car! I have a '67 in my driveway, but only a straight six.

Most of my previous shifting was done on either low HP FWD (Sentra, Saturn), and several 89-93 Mustang 302's, most with Tremec T5 and centerforce clutch setup. You know, I never would give throttle when upshifting until the clutch was all the way up in these cars (normal driving of course), and it was always smooth. That's probably why I'm having trouble adjusting.

I'm very afraid to break the TL's MT!! Wish we could install shift stops like the old aftermarket shifters...

Brett - I totally agree about bikes being easier to learn and master! Most of my riding is on sportbikes (see signature for the current flock) -though my back is telling me to give it up. Much easier to shift due to a bunch of specifics I'm sure.

Good explanations on power shifting in the above posts also. I'm a bit afraid to clutch with WOT though, I'll just stick to doing the normal shift, only a lot faster!

 

Yeah, this has been one of the better threads (except for a few moments) on the topic. Always good to get other people's take on the subject as far as I'm concerned.

I was the orginal owner of my 1966 Chevelle having ordered it in March and taking delivery 4 weeks and 2 days later. I had to settle for it because my step-father had talked my mother out of signing the loan note for a 1966 427 Corvette I had ordered the previous November. God, I wanted THAT car. So my Chevelle had some interesting options I had specified.. like nothing to rob the engine. No A/C, no power steering, not even power brakes. I ordered the L34 engine (360 HP) and the close ratio Muncie M21 tranny (2.20 first). The car was Madierra Marron with a black vinyl top and black interior, full instumentation (yes even the knee-knocker tach), simulated wood steering wheel, some other goodies, and sintered metallic brake linings (a rarely optioned item). Out back were 3.73 gears and positraction, of course. Later I installed Hooker Headers, an R3310 780 dual feed Holley (to replace the single feed 660 Holley), LS6 valve springs and retainers, Load Leveler rear shocks, Mickey Thompson 10" street tires out back, glass packs, and the obligatory must work on the secondary throttle arm of the Holley to alter the vacuum-operated secondaries. The car ran 13.2's in stock condition and 12.8's modified.

As for power shifting the TL, you most definitely DO NOT want to do this. This ain't no 60's American supercar. Those were built for that kind of abuse.. the TL is not and will break in short order. The shifter on the TL is not made for power shifting.. too short, not a good grab, and you'd tear it up after a few times of this. Not to mention the drive train.