3 - 2 downshift

bunnyc

bunnyc

Senior Member
My '29 is getting better and better. Engine runs good. Doesn't overheat. Steers good. Got the parking brake working. Service brakes are good.
Now, if I could just downshift from 3 to 2 without grinding gears!
Yes, I double clutch. Tried idle speed (600 rpm) and bumping the throttle passing through neutral. Neither has worked.
It's to the point where I just leave it in 3rd and lug the engine, that's not good.
Anyone have technique suggestions?
 
I've been working on my "technique" too...I'm successful part of the time...

From the Manual..

Shifting Back Into Low Speed
When shifting from high to second speed, at car speeds
not exceeding 15 miles per hour, there should be no hesitation
in neutral; after disengaging the clutch the lever should be
moved as quickly as possible, from high to second speed.
Should it be necessary to shift from high to second at higher
car speeds, it can be done by the following method:
Disengage the clutch and shift into neutral. Reengage the
clutch and at the same time accelerate the engine; then dis·
engage the clutch again and shift to second, after which reengage
the clutch. With a little experience, this shift can be
made quietly.
 
When downshifting, you have to rev the engine A LOT more RPMs than you think is necessary. It feels like the revs are going to be too high but it takes practice. Also, lightly hold the shift knob with your fingers and shift delicately, don't grab it with your fist.
 
Try blipping the throttle after neutral, and don't be afraid to give it a good shot. Once you find exactly how much to get a smooth down shift, you'll find you can fine tune it down. Of course timing is everything, and every A is different. Your miliage may vary!
 
You push in the clutch to take it out of third, let the clutch out and blip the throttle, push the clutch back in and slide it into 2nd.
Keep Practicing.:) It'll come to you. You'll get used to the sounds and the feel of what works,
Good Luck:)
 
Try making that shift at lower speeds at first. Once you get that figured out you can start doing at higher speeds.
I'm not in the throttle blipper camp. Once the clutch is pushed in and the lever slipped into neutral, as the clutch is being let out raise the engine speed, push the pedal back in and in lightly feel your way into second and let out the clutch while your foot keeps its position on the throttle. You'll need more engine speed than you think at first.
 
Instructions given are GOOD. BUT, it just takes practice, practice, practice, until you get the "FEEL" of it. Once you get that proper "FEEL", you can do it automatically, without even thinkin' about it!
I FINALLY got to where I could downshift Minerva to second from 30 MPH, without even a sound. Being able to do this is a MUST, when going DOWN MOUNTAIN GRADES!!! With a lots of practice, you can even master down shifting from SECOND to LOW!!!
Bill W.
 
bunnyc said:
My '29 is getting better and better. Engine runs good. Doesn't overheat. Steers good. Got the parking brake working. Service brakes are good.
Now, if I could just downshift from 3 to 2 without grinding gears!
Yes, I double clutch. Tried idle speed (600 rpm) and bumping the throttle passing through neutral. Neither has worked.
It's to the point where I just leave it in 3rd and lug the engine, that's not good.
Anyone have technique suggestions?
Click to expand...

"Passing through neutral" sounds like you are not letting your foot off the clutch, then revving up the engine, but rather just sliding from 3rd to 2nd. It's very important to be in neutral and left your clutch completely out, then rev the engine, push in the clutch and shift to second. As mentioned, it's a big ratio jump between 3rd and 2nd, so you need more engine speed than you'd think.
 
Agreed that you need more than just a blip on the throttle!

I had tried this technique with just a tap of the throttle, and still grinded. Then I tried by giving the throttle a good solid press and brought the engine revs real high, and then it slid right in to 2nd, without even a knock.
 
all that is said above, after a short time it will be second nature, but until then there will be some noise. Best to start at low speed like the directions said 15 MPH is a good place to start. It is good that Henry gave the Model A a trans that can take the abuse of all of us "getting the feel"
 
Ray's right, you have to give her a hardy rev before you slide her down in gear. Then it's like a knife through butter (with a few crushed nuts sprinkled in there sometimes).

Wally
 
And keep the rpms up to match the rpms at the lower gear.
I found that when I got the hang of it I was not fully depressing the clutch, just taking the slack out. The transmission slipped into the lower gear at the correct rpm.
 
Most of the above advice is very good, especially how you will need to rev the engine more than you first thought. Try it at 15 mph first. To give an idea how fast you should rev the engine with the clutch out and in neutral, leave the car in 2nd gear and take it to 15 mph. Now LISTEN TO THE MOTOR before you shift into top. That is how many revs you want (or slightly more) as you shift into 2nd on the down shift. The whole idea of double declutching is to match the speeds of the gears so they engage without grinding.
Once you haave read all this, go out and practice;)
 
Ray in La Mesa said:
When downshifting, you have to rev the engine A LOT more RPMs than you think is necessary. It feels like the revs are going to be too high but it takes practice. Also, lightly hold the shift knob with your fingers and shift delicately, don't grab it with your fist.
Click to expand...

^^^This!

Example; Lets say I start my downshift at 25MPH. By the time I'm in 2nd, I'm at 20 MPH:

When I double clutch, with the clutch out in neutral, I have to rev the engine up to a little bit more than the revs will be at 20 MPH, then dip the clutch and slip the lever into 2nd.

Now if you drive in 2nd at 20 MPH, the engine is revving FAR higher than a quick "blip" of the throttle will acheive (in a stock car anyway).



The press of the throttle I use in the A, would have my modern cars bouncing off the rev limiter at 7000 RPM, because they react so much faster.

The reason is: 1st and second are very close, then there is a HUGE gearing gap upto 3rd, so going down means you need to account for the gearing gap with engine revs, and that big heavy flywheel doesn't like to accelerate quickly, so a good press of the go pedal is required.
 
YEP, ALWAYS OVER REV & when the REVS are comin' down, you learn "just when" to slide into second gear. IT'S SORT OF LIKE A "FUN" GAME!
Bill W.
 
Thanks for all the response. I'll practice what I have read here. I just hope I master it before tearing up the transmission!
 
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