What is the trick for smooth Shifting

i have double clutched all my life ! big truck & my "A" . but i just put a s-10 5 speed in my car . best improvement ever !!!!!!!!!!!!!
 
I've tried it both ways. I'm more often able to get a smooth shift when double clutching, and here's my explanation:

The key to a smooth shift is that the input shaft of the ****** has to turn at the correct speed for the desired gear. You determine the correct speed through experience by listening to the engine note. When double clutching, the input shaft stays connected to the flywheel through the clutch as the engine winds down, and is always spinning at the same rpm as the engine. If you don't double clutch, the input shaft is de-coupled from the flywheel as the engine winds down, and you can't be assured the speed is correct by the engine note alone.
 
We always double clutch ours. Like others have said it is not so much the act of double clutching but the time given to allow wheel speed to equal gear speed. Shifting a crash box is a developed skill. When we first start off with the transmission cold we double clutch but do it quicker, after about two miles when I come to an intersection and have to go back through the gears I double clutch through the shifts but linger a bit longer but not too long or it will really clash. If going through the gears while traveling down hill you need to make the shift quicker before wheel speed increases too much are you will have to stop and start over to shift at all. We don't do creepy take offs. I don't wind it out to the max but keep up the momentum and never lug or skip gears. I am currantly using the 600w gear oil from Snyders it is 250 weight as originally used. I'm not so sure that 90 wt. might even work better. A few years back it was the general consensus that STP was the best choice for gear oil . I filled the transmission in our 31 tudor with STP and ran it that way for a few years. I noticed that it shifted worse than the other model A's so I decided to drain the transmission and try some gear oil from Snyders. I removed the filler plug and the drain plug and after more than an hour not one drop of the STP had drained out. I ended up having to use a heat gun to heat the transmission for about 30 minutes before it drained. After replacing the STP with Snyders gear oil it shifts just as well as our other model A's. Anybody can do as they please but no more straight STP for me.
 
Bruce said:
Going from first to second or second to third: double clutching just gives you something to do while waiting in neutral for the instant the RPMs hit idle speed.
Shifting properly is just correct timing. If you get your timing down pat you can even shift without declutching.
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I totally agree! I'm too old and tired to waste energy on double clutching on upshift.
Did I just hear a bell ring??? I just became a SENIOR MEMBER!!
 
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I think I am getting back my feel for the crash box trans. After about 150 miles,going to different cruise nights I can make most all shifts clean,and silent. The trick was idle speed,and more patience. I had been keeping the idle speed up,for fear of stalling during stops. The lower the idle speed the easier it is to shift.
 
I double clutch out of habit... but, if you realize this isn't a sports car that has to be wound out in every gear, then shifted, you are wrong. for normal puttin' around, listen to the motor and shift a bit slower than you think you should. Shift at 5-7 mph and 12 -15 mph, let the gear shift fall into the gear with a minimum of pressure and you should have smooth quiet gear changes.
 

I agree with Bruce,
I have no trouble shifting, and have instructed a few drivers that have had trouble, most were doing all kinds of tricks on the up shift when it is just a matter of letting that heavy flywheel and engine idle back down to the proper rpm to match the next gear, most used up that time randomly pumping the clutch.
On the down shift there is a double clutch trick needed. Every car will have little different feel due to adjustments and the condition of the parts, but the theory is the same.
You must match the engine rpm to the transmission gearing; the closer you do this the easier it will be. At the top of the perfect scale you can shift without the clutch but you must match the two exactly, not imposable but a misjudgment could cause damage.



Bruce said:
You asked for "the trick."
It is patience.
You have to clutch and then wait ... wait ... wait for the trans speed and the engine speed to match up. I'm convinced that the double-clutch is just a time allotment, like saying, "one chimpanzee, two chimpanzee ..." Get the waiting perfect and you wouldn't have to double clutch at all.
Downshifting from 3rd to 2nd is just the opposite. You must increase the engine speed to match the transmission speed. It is harder to do, but the same trick applies ... patience.
Click to expand...
 
I agree with Marshall 110%. As an old truck driver I can tell you that you will normally double-clutch only on the downshift. Marshall has it right, Model A's have a heavy flywheel so you need a small amount of patience when you upshift to give the engine rpm's a chance to slow down to match the transmission rpm's...I think that is where some of you mistakenly got the idea that double-clutching is the thing to do. Also I learned recently about how the spark advance can help in certain situations to avoid gear-clash. Cheers & have fun out there!
 
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