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shift points

ksurfer2

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My 69 RR with 440 and 727 runs great. My question has to do with the shift points of the trans. When I take off from a dead stop, the shifts seem to happen almost immediately from 1-2 and then 2-3. This was occurring with my original trans, and I now have a brand new trans from John Cope racing that is doing the same thing. I followed all the instructions on setting the kickdown lever. However, with it adjusted per the instructions, at fully opened throttle, there is still about another 1/2 to 3/4 of an inch of available movement to the linkage. No matter how I try adjusting, I cannot get a full throw of the linkage (it is almost as if the lever in the linkage needs to be a bit longer). When traveling at slower speeds and going to full throttle, it does not downshift (same issue with original trans). I have 4.10 gears and plenty of power, so it is not too much of an issue, but I would like to make sure the trans is operating properly. Fluid level is right at the full mark on the dipstick with the trans warmed up and idling in neutral.
 
The 4.10 will shift earlier as the shift points are based on driveshaft rpm. Is the full throttle the shift rpm is too low? A&A sells higher rpm governors. They can be swapped in the car by removing the trans crossmember, trans mount, and tail shaft housing.
Doug
 
check this video out, it will help with the adjustment.

 
If I am understanding the video correctly, the important part of the adjustment is the kickdown rod pushes the lever fully back at wide open throttle. If that means that the lever is not fully forward at idle, then that is OK????
 
Normal part throttle acceleration would probably put your car into third gear at 13 to 15 mph.

However, you should be able to get full throttle down shifts at reasonable speeds/rpms and should be able to adjust more travel from your factory linkage.

1) is your carb throttle plates full open?
2) I believe that two of the three linkage rods are length adjustable. Have you adjusted them both to near full length?
3) check the two bell cranks and tranny lever arm to make sure everything is correct with them.
 
If that means that the lever is not fully forward at idle, then that is OK????

you want it fully forward at idle , so when you step on the gas you change the pressure in the transmission to match the pedal position
 
That is where I am having issues....I cannot get it adjusted to be fully forward at idle AND fully back at full throttle.
 
Stock carburetor or aftermarket? If aftermarket, correct throttle lever adapter? The lever does not have to be full back at full throttle.
 
Stock carburetor or aftermarket? If aftermarket, correct throttle lever adapter? The lever does not have to be full back at full throttle.
6 bbl, stock linkages.

If the approx 1/2 inch of further movement I have at the linkage at wide open throttle is ok, I will leave as is.
 
Are you sure the throttle pressure lever is original? There are variations in the center to center distance of the holes and any change is a "leverage" change, affecting linkage stroke.
Mike
 
Are you sure the throttle pressure lever is original? There are variations in the center to center distance of the holes and any change is a "leverage" change, affecting linkage stroke.
Mike
I am not sure of the originality of the pressure lever, but I suspect what you are referring to is the issue.
 
I am not sure of the originality of the pressure lever, but I suspect what you are referring to is the issue.
I have over 20 TF cores. Measure your lever and I'll see if I have a shorter one. Is it a two hole model or hole and ball stud?
Mike
 
If it's not kicking down on full throttle then it shouldn't be left alone as it's not working as it should. Sometimes with aftermarket carbs it seems the slot in the lever is too long to get the adjustment correct at both ends - I've got a small nut and bolt in mine to reduce the size of the slot. It allows the kickdown lever to move as soon as there's throttle pressure, and also allows full kickdown at full throttle.
 
Here is a pic of the linkage that is on my car:

linkage 1.JPG


This is a pic of another off a 6bbl that I found online. They appear to be different.

Linkage 2.JPG
 
They are different but work the same. U need to have the lever on the trans all the way back when at wot. U will notice that there is no spring pressure on the lever till it is pushed back approximately 1/3 of the way. That’s how their designed. The rod that is going up and down try adjusting it first. Unscrew the adjuster so it’s only on about 4-5 threads, u want it to be stable not wobbly. Then adjust the top rod length. See where u r then. At wot u should have a little slack, just so u can slide a 1/8 drill bit in there. Hope this helps. Kim
 
6 bbl, stock linkages.

If the approx 1/2 inch of further movement I have at the linkage at wide open throttle is ok, I will leave as is.

This is not clear for me. Do you have 6 bbl carbs and factory original 6 bbl carb linkage? Or do you have stock 4 bbl linkage?

The 4bbl linkage will not work on the 6bbl without some modifications.
 
Last edited:
This is not clear for me. Do you have 6 bbl carbs and factory original 6 bbl carb linkage?

The 4bbl linkage will not work on the 6bbl without some modifications.

And, if this is the case, the vertical rod will need to increase in length, and the carb rod will need to get shorter. Your problem is likely the upper bell crank is too far over center to generate enough travel, if I remember correctly.
 
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