AMC Eagle Den Forum

The Shop => Transmission Shop => Topic started by: Mr_Roboto on May 25, 2022, 11:11:07 PM

Title: Yet another linkage question
Post by: Mr_Roboto on May 25, 2022, 11:11:07 PM
So I have an Offy 4bbl Intake Manifold on my 258 and it clearly says "not for use with an automatic transmission" in the little documentation I can find. Naturally, that means I want to use it with an automatic transmission.  ;D

I've got the bracket, the kickdown linkage rod and a throttle cable and no springs either on the trans end or the linkage end. This naturally brings a few questions up:
1-Can I fabricate a method using the kickdown mechanism as it is to use a carburetor that's got its shafts mounted going front to back instead of driver's side to passenger side like the stock carb linkage seems to? I am thinking about a chunk of universal throttle cable of some kind going to the carb.
2-How do universal  kickdown cables work out? It seems as if the mechanism for these is somewhat more complex from the factory and obviously am concerned about transmission longevity.
2A-Would I want a universal spring at the carb if I used a to connect to the original linkage? I lean towards yes.
2B-What kickdown springs should I use and where do I get them at?
3-Would a universal cable based kickdown and throttle cable be enough to solve this problem? If so I think I could make a bracket to get that working with a set of carb mounted return springs
Title: Re: Yet another linkage question
Post by: rmick on May 26, 2022, 12:52:45 AM
The universal kick down cable with a return spring is an option I have used on other AMC's when I didn't have the original linkage or had used a Clifford intake on a six cylinder.
Title: Re: Yet another linkage question
Post by: Canoe on May 28, 2022, 12:03:37 PM
I always get a little worried when someone starts talking "kick-down".

Everything I've heard over the years, is that it's not actually a kickdown, it's a proportioning valve. And it has to be correctly adjusted or you'll burn out your transmission. Which is exactly what happened on my '81, to the part that handles Reverse & I think it was 1st gear. Turns out the tech adjusting it couldn't get it to secure at the correct spot, so he just secured it and left it - but without telling me...

So if someone is fabbing up something to replace the "kickdown" setup on the Eagle, are they going to end up with a kickdown or the Eagle "kickdown" that controls the proportioning valve correctly.
Title: Re: Yet another linkage question
Post by: Mr_Roboto on May 28, 2022, 12:33:12 PM
Indeed kickdown is a misnomer, in GM land they call it a "TV cable" and I've seen it called a "detent cable" as well.

The return spring would go on the trans, correct? Just wanting to be sure I understand things correctly.

Also, is there an optimal distance from the center of the throttle shaft out to the cable stud I should be using?