904 Kickdown linkage

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KJoeZ61

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I'm sure this has been asked before but I cant find it. The attached picture shows my linkage as it rests. My question is the lever on the transmission can travel about a half inch more at full throttle, but wont as it's adjusted. So should I adjust it more that the lever on trans is more engaged at rest?

IMG_0990.jpg
 
Could it be because you have a 2 barrel top rod linkage and not a 4 barrel? It looks like you’re holding on to 3/4 threads with leads me to believe so.

Jake
 
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What’s the geometry look like of that linkage from the throttle bracket to the carb? With a lot of threads visible on that linkage, you might have a 2bbl rod trying to do the job of a 4bbl rod.

Here’s a comparison of a 2bbl rod and 4bbl rod.

[WANTED] - 4-bbl kick-down rod
 
You can use the 2 bbl rod on the 4 bbl if you add about 1 1/2" more thread...
 
At wide open throttle, when you push back on that kickdown linkage, you should have approximately a quarter of an inch of play.
You do not want the kickdown linkage to bottom out that kickdown lever on your valve body. you can break things or pull things apart inside where the valve for the kickdown is.
 
I'm sure this has been asked before but I cant find it. The attached picture shows my linkage as it rests. My question is the lever on the transmission can travel about a half inch more at full throttle, but wont as it's adjusted. So should I adjust it more that the lever on trans is more engaged at rest?

View attachment 1715204062
What RPM does it shift @ WOT ?
 
There is no way I can make it any longer, not even a quarter of an inch. If I go any longer it won't fit on the throttle linkage without binding. The first picture shows it resting without the spring. Second picture shows throttle floored the the kick down as far back as it will go.

IMG_0992.jpg


IMG_0993.jpg
 
The angles/geometry of your throttle/pedal cable is off. It should be in a straight line from the throttle cable/kickdown bracket to the carb attachment. You’ve got the same problem with the kickdown rod too.

You may need an adaptor for Mopars for your carb which corrects that geometry.
 
Ditch the linkage altogether and get you a cable conversion from Bouchellion or Lokar. Solves most of the problems and easily adjustable. You can always sell the linkage and recoup some money.

A65C7E27-4BD0-4363-9896-423370EC16DB.jpeg
 
Ditch the linkage altogether and install a manual valve body. Solves all the problems and shift points are easily adjusted with your right arm.:D
 
There is no way I can make it any longer, not even a quarter of an inch. If I go any longer it won't fit on the throttle linkage without binding. The first picture shows it resting without the spring. Second picture shows throttle floored the the kick down as far back as it will go.

View attachment 1715204205

View attachment 1715204206
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In the second picture you need to screw the end on to the rod so that you have a quarter inch of free travel at wide open throttle with the linkage all the way back.
In the first picture it does not matter where that linkage sets once you put the spring on it it will pull it Forward against the pin. The purpose for that long slot is so that if your kickdown linkage binds your throttle can return to idle. What counts is at wide open throttle you have a quarter inch or so of play to keep from bottoming out the kickdown. You do not need to extend that rod in the second picture you need to screw the end on so it slides over that throttle pin.
 
Does this look any better? Is this the correct spacing

View attachment 1715204321

View attachment 1715204322
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In tbe first picture you need to push the kick down back as far as it will go at the same time the throttle is all the way back. Then adjust to the pin.

If in the picture it is all the way to the back then you need to adjust it back(forward) for Less gap between the pin and the slot.
 
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I'm sure this has been asked before but I cant find it. The attached picture shows my linkage as it rests. My question is the lever on the transmission can travel about a half inch more at full throttle, but wont as it's adjusted. So should I adjust it more that the lever on trans is more engaged at rest?

View attachment 1715204062
The linkage between bell crank & trans needs adjustment.Do you see the hole in bell crank?Disconnect that rod, then put a drill bit in the hole then push link down and adjust it so it just snaps back on .
 
I though we were going for a 1/4" gap there. Your saying close the gap so it's just about touching?

You will feel the play at the end of the travel.
If in that picture the travel is all the way at the back I would close that Gap to about half of what it is but once again just goes by how it feels at wide open throttle. Just don't force it.
Drive it try it out.
 
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