How to hook up kick-down cable th350? [Archive] - Chevy Nova Forum

: How to hook up kick-down cable th350?


NovaNate
24th-February-2006, 12:15 PM
Anybody have a photo or good description of how to hook up the kick down cable from a th350 to a edelbrock carb? Any tricks to adjustment? I'm a little confused looking at the long slot on the kick down cable end, and the available holes in the carb throttle lever. Which hole do I stick it to? Outside or inside of throttle lever? What kind of fastner?

BTHOMAS67Wagon
24th-February-2006, 01:11 PM
Without posting a pic, I'll try to help...

First, you will want the Detent/Kick down to be on the "bottom part" of the throttle linkage on the carb, so that when you depress the pedal your accel linkage will pull the throttle linkage back and rotating the detent part of the linkage foward. (I hope that makes since ?!)

The detent cable as you mentioned, has the long slotted hole in it, which will attach to the throttle linkage and when the stud (can be bought anywhere) reaches the end of that slotted hole, it will pull the detent cable.

When you are at WOT (wide open throttle) you want the detent to be at the end of the pull. (and remember, just because you are pulling WOT at the carb, doesn't mean that your pedal is pulling it that far. So WOT, should be measured with the pedal.)

Hopefully that helps and maybe someone can explain it in words better then myself ?! :o

-Brent Thomas
Ohio

DANNO
24th-February-2006, 02:07 PM
Here's mine:

http://img.villagephotos.com/p/2002-12/73952/OOTYQ-IMG_0157.JPG

malcom2073
24th-February-2006, 08:45 PM
Awesome, I've been wondering how to hook mine up as well, figured it was something like that, the pic helped thanks.

novacharlie
24th-February-2006, 11:21 PM
I un hooked mine completely and soldered the end shut. I figure with the mega shift I can down shift just as well. Anyone else disconected theres?

Chuick

68chevyll
25th-February-2006, 07:48 PM
Mine is not hooked up either.

footbrake68
25th-February-2006, 10:28 PM
Yep ... good pic Danno - we hooked ours up to hit about 7/8 throttle input after installing the new motor ... then the new cable was promptly melted by the new headers :eek: :D :) ... so just make sure you route it away from the hot stuff in the engine bay.

We just got in a hurry to hear it run and drive it down the road :D .

BTHOMAS67Wagon
25th-February-2006, 10:42 PM
Okay, you all offically threw me for a loop on this ?!
You didn't hook up your kick down ?!
Why!!!

How do you pass?
How do you "get up and go"?

Did you switch you valvebodies or soemthing from stock?

:confused:
-Brent Thomas
Ohio

DANNO
25th-February-2006, 11:16 PM
The kickdown is just a way to downshift with your foot (what we used to call, "passing gear"). If it's not hooked up, you just manually downshift.


Dan (but mine's hooked up);)

novacharlie
26th-February-2006, 11:00 AM
No valve body changes. If you manually shift there's no need for a kick down, the 4 barrel has enough power in its self. Most street rodders disconnect them.
Chuck;)

Carl Stevenson
26th-February-2006, 11:09 AM
I welcome correction if I'm wrong, but I thought a TH350 needed the cable hooked up to make correct/more pressure in the transmission for the shifts. What I mean by that is I thought the shifts were on the lame side if the cable is not pulled out as the the throttle opens. For example, if the cable was permanently pulled 3/4 of the way out, would the shifts not be firmer than if it was at rest?

Carl

BTHOMAS67Wagon
26th-February-2006, 01:37 PM
Most street rodders disconnect them
Forgive me for sounding argumentative, but I completely disagree !!
(IT makes no sense !!)

Again, Why not just hook it up?

So, you are telling me that if you jump on the freeway are you need to pass someone at 50-60 mph, you drop it down to "D2" ?!

Have you ever missed "D2" and dropped down to "D1" (and listened to your engine and transmission loose a little life)?

I have only been in and floored a couple of cars that the detent was not hooked up (all being 350's w/4bls) and never have I had one "get up and go", but instead boog down and slowly gain speed. Again, why not just hook it up?!

I ONLY couple of reasons I can think of is that so that someone can make it sound like they are "manually shifting", they don't know how to hook it up, or they are jump too lazy.

There are NO reasons I can think of that they would be against hooking it up?!

PLEASE, someone chim in if they can change my way of thinking ?!
:)

-Brent Thomas
Ohio

Repointer
26th-February-2006, 02:45 PM
The kickdown is just a way to downshift with your foot (what we used to call, "passing gear"). If it's not hooked up, you just manually downshift.


Dan (but mine's hooked up);)

This is what I understood. I never had mine hooked up all last year. Use my hand instead of foot for passing. (Or I should say hand and then foot:D ) Not a problem for me. I did ask the guy who just rebuilt my turbo 350 about it and he said it IS harder on the tranny if you leave it unhooked and manually shift. I couldn't tell you why though.:)

DANNO
26th-February-2006, 06:46 PM
I welcome correction if I'm wrong, but I thought a TH350 needed the cable hooked up to make correct/more pressure in the transmission for the shifts. What I mean by that is I thought the shifts were on the lame side if the cable is not pulled out as the the throttle opens. For example, if the cable was permanently pulled 3/4 of the way out, would the shifts not be firmer than if it was at rest?

Carl
You may be thinking of the Throttle Valve cable in overdrive trannys. Those must be hooked up and properly adjusted.


Dan (maybe?):D

Ray_McAvoy
26th-February-2006, 07:23 PM
I welcome correction if I'm wrong, but I thought a TH350 needed the cable hooked up to make correct/more pressure in the transmission for the shifts. What I mean by that is I thought the shifts were on the lame side if the cable is not pulled out as the the throttle opens. For example, if the cable was permanently pulled 3/4 of the way out, would the shifts not be firmer than if it was at rest?

Carl

I agree with Carl. According to the service manual, the TH350 detent (kickdown) cable connects to both a detent valve and a detent pressure regulator inside the valve body. In addition to downshifting, it also increases the line pressure that's applied to the clutches. That increased pressure helps prevent the clutches from slipping.

I did ask the guy who just rebuilt my turbo 350 about it and he said it IS harder on the tranny if you leave it unhooked and manually shift. I couldn't tell you why though.

The reduced pressure is what would make it harder on the transmission. It could allow the clutches to slip under the load of hard acceleration.

4door64
26th-February-2006, 07:32 PM
The kickdown on my car dosent work all the time only when it wants to so sometimes I just shift down, but the other day I was going about 45mph and I droped it into 1st instead of 2nd and boy do I wish I wouldent have. TH350's are strong but just hope you dont mess up like I did especually if your going faster then I was.

NovatoriusRex
26th-February-2006, 11:19 PM
I agree with Carl. According to the service manual, the TH350 detent (kickdown) cable connects to both a detent valve and a detent pressure regulator inside the valve body. In addition to downshifting, it also increases the line pressure that's applied to the clutches. That increased pressure helps prevent the clutches from slipping.
The additional line pressure is only applied when the detent cable is pulled out far enough to activate the kickdown, usually at WOT. At anything other than WOT, it does nothing.

This what the guy who built my kickdown cable at the trans shop told me when I asked him about it before having him fab up my kickdown bracket.

The Dude
27th-February-2006, 01:00 AM
That I'd like to know is exactly how to go about connecting a kickdown cable inside the transmission without bending up all the linkages or the cable itself. My TH350 currently has a "late" style cable and I will need to replace it sometime down the road after the engine's in.

Ray_McAvoy
27th-February-2006, 02:39 AM
Hi Dude,

The lower end of the cable has a small tab on the end with a tiny hole in it. The linkage "rod" from the transmission is basically a stiff wire with a zig-zag bend in the end.

Once you remove the small bolt that secures the cable jacket to the transmission case, you can pull the jacket out away from the case. If you do this with the carburetor end of the cable disconnected, you should be able to pull it out to the point where you can clearly see the tab with the tiny hole hooked on over the zig-zag bend in the end of the wire link.

What you need to do is carefully turn the tab sideways as you thread it up over the bend at the end of the wire link. Installing the new cable is very similar. Turn the tab on the end of the cable sideways and guide the hole in the tab over the wire link. Allow the tab to turn back to it's "normal" position inline with the cable as it goes around the first bend in the wire link. This is where the tab needs to be ... between the 1st and 2nd bend of the zig-zag. Now slide the cable jacket straight down into the transmission case being careful not to bend the wire link rod.

BTHOMAS67Wagon
27th-February-2006, 08:04 AM
----- Commented out by BTHOMAS71CHEVY -----

The Dude
27th-February-2006, 02:09 PM
Hi Dude,

The lower end of the cable has a small tab on the end with a tiny hole in it. The linkage "rod" from the transmission is basically a stiff wire with a zig-zag bend in the end.

Once you remove the small bolt that secures the cable jacket to the transmission case, you can pull the jacket out away from the case. If you do this with the carburetor end of the cable disconnected, you should be able to pull it out to the point where you can clearly see the tab with the tiny hole hooked on over the zig-zag bend in the end of the wire link.

What you need to do is carefully turn the tab sideways as you thread it up over the bend at the end of the wire link. Installing the new cable is very similar. Turn the tab on the end of the cable sideways and guide the hole in the tab over the wire link. Allow the tab to turn back to it's "normal" position inline with the cable as it goes around the first bend in the wire link. This is where the tab needs to be ... between the 1st and 2nd bend of the zig-zag. Now slide the cable jacket straight down into the transmission case being careful not to bend the wire link rod.


Yeah. I figured it was one of those, "jiggle and jaggle and eventually it'll slip right in" kind of deals. I'm going to try it with the pan off so maybe I can get at the linkage inside and save myself a little hassle. (That tab connects to another rod that connects to a lever and yadda, yadda, yadda.) We'll see. Gotta get the engine in first. (long story.)

69NovaSS
27th-February-2006, 02:17 PM
personally what I would do is have the new cable nearly in place but neither end of the original cable unhooked yet. Then you would unhook the tranny end of the cable and pull up on it gently. You will see the lever come up with the cable...grap on to the lever with a pair of needle nose lock pliers so the end you hook is visible.(this way it cannot fall back in the tranny by accident) You then pull the old cable off the lever and hook the new cable up to the lever...remove the pliers and slowly lower the cable back into the tranny so you can bolt it up. Then you go to the carb and unhook the carb end and hook up the new cable...pretty easy

DANNO
27th-February-2006, 06:57 PM
Danno, Are you removing my threads again ?!?!
:confused:

If so, WHY ?!?!

I said nothing against anyone ?!?!

:confused: :confused: :confused: :confused: :confused:

-Brent Thomas
Ohio
I have no idea what you are talking about. You need to address this paranoia.

jade76
28th-February-2006, 10:13 PM
This is a good thread.

I don't have mine hooked up. I did at one time, but it didn't take long for the headers to burn through. I shift it manually to 2nd if needed, but usually there's enough power to not need the kickdown. Also, I have a B&M Hammer Shifter which also prevents me from accidentally shifting to 1st.

The kickdown can become a nuisance if you like to put the pedal to the metal more often than not, which could burn the tranny out just as fast, or possibly faster than manually down-shifting it. Might as well just leave it in 2nd for that matter. lol

But I do like to shift, so I'm going to convert to a 4 or 5 spd, and that'll solve that problem.

Punksnoted
3rd-March-2006, 03:29 AM
Basically what guys (most of the ones ive seen) do when they take the detent cable out is they put a plate to lock the kickdown valve in the WOT position which gives you more line pressure all the time as opposed to only when you stomp on the pedal. just my 2 cents.

Pro-touring72
3rd-March-2006, 03:44 AM
Basically what guys (most of the ones ive seen) do when they take the detent cable out is they put a plate to lock the kickdown valve in the WOT position which gives you more line pressure all the time as opposed to only when you stomp on the pedal. just my 2 cents.

What this would do is increase heat build up in the fluid. It would be OK for the drags but I wouldnt do this on the street.

As for not hooking up the detent. I never had one my self till my last tranny wipped out the second gear clutches. The low line pressure when manually kicking it into pasing gear caused them to slip till they cooked them selves after a few summers.

I hook mine up now but still use the old ratchet shifter for the kickdown duty. the dentet is woking the line pressure. :beer:

novacharlie
11th-March-2006, 08:16 AM
OK here's the scoop from the professionals. I called 6 of the local tranny shops in my area. I asked them if the dedent cable is disconnected (on a 350 turbo) would it have any affect on pressure or tranny. There responce was no affect what so ever, it will not cause slippage or affect line pressure. They said on the 350 & 400 turbo the modulator valve controls this. But if you do this with a 200 or 700 it will definitely burn the tranny as this cable also controls line pressure etc.. They said the only thing it is used for on the 350 & 400 is to automatic downshift when passing.

Chuck:D

steelrat
25th-July-2006, 06:32 PM
Without posting a pic, I'll try to help...

First, you will want the Detent/Kick down to be on the "bottom part" of the throttle linkage on the carb, so that when you depress the pedal your accel linkage will pull the throttle linkage back and rotating the detent part of the linkage foward. (I hope that makes since ?!)

The detent cable as you mentioned, has the long slotted hole in it, which will attach to the throttle linkage and when the stud (can be bought anywhere) reaches the end of that slotted hole, it will pull the detent cable.

When you are at WOT (wide open throttle) you want the detent to be at the end of the pull. (and remember, just because you are pulling WOT at the carb, doesn't mean that your pedal is pulling it that far. So WOT, should be measured with the pedal.)

Hopefully that helps and maybe someone can explain it in words better then myself ?! :o

-Brent Thomas
Ohio


Great info. I have one problem my cable seems to be stuck, it will not travel forward so that I can hook it up to the throttle linkage. Do I need to delve into the tranny to address this?

thanks