kick down linkage adjustment
 

Hi all. Ever since I replaced the 630 cfm AVS with a 750 cfm AFB from Ederblock, I have issues with the kick down linkage (these were there, before the engine partial built up, head work, bigger valves, cam, see 440 build for Imperial in the Engines page). Well, I have extended the horizontal rod on the carburetor to the mazimum, still shifts from 1st to 2nd at an indicated 15-16 mph no matter what the throttle. 3rd comes at around 20 and change, regardless.

I am thinking of adding an extension. I can go and get an allthread, and attach it on the current linkage, may be with a couple of small hose clamps (have no welder). Any idea what is the thread size? Looks like some sort of fine thread.

Thanks

WHY don't you get the correct throttle lever adapter or lockar setup. Stop screwing with the trans....

Can you please explain?

EDELBROCK makes a Chrysler adapter

Thanks, will look into it.

For now, I extended the current linkage by about 1/2 inch, needs more.

But I still don't get it, the range of motion is identical, since we still have the same throttle cable.

The car started missfiring big time as I was testing this morning. The dwell on the points was from 18 to 10 degrees as I was revving up. These mechanics messed everything, apparently. Makes no sense to have anybody work on your car. Even reputable shops like that one mess up big time (there is a long list of what else they messed up).

V8 4bbl setup has the rod setting higher than the 2bbl

Thanks, this is a 440. Always 4bbl.

At 25 degrees dwell, the car ran good enough to test. I had to advance a bit to compensate, but not sure how close I am close to the sweet spot yet.

I extended the rod another 1/4 inch or so. Finally, we got a sign of delayed shifts, and even a bit of down shift to first when held on low 2. A little more, and it should be willing to rev all the way to 45-5000 by itself.

Still don't get why I had to extend the rod. The throttle movement range is the same.

Have you compared the radius from the throttle blade shaft to the attachment point.

Also how far forward and back from vertical do they travel.

I've found the angle through the travel changes the speed the horizontal moves and can result in different shifting speeds.

Did not compare to the old carburetor, but it will have to be close, because with both carburetors, the same throttle cable linkage opened the carburetor all the way. In other words, about 2 or 3 inches (or whatever it is) throttle cable movement got you from idle to WOT in both cases. But in the new setup, I had to extend the linkage by about 1.5" to get it to do anything.

Anyway, at least I am close to getting it to work properly.

Throttle cable has nothing to do with the kickdown. It has to do with the arc it travels in

Glad to hear your getting close. Maybe just another one of lifes mysteries but it would be nice to know what changed so you can fix it if it crops up again.

Getting her shifting right is the main goal.