No Kick down 904

by **Goldenblack440** » 20 Jun 2009 12:22

I have just spent the last hour or so going through past posts on kickdown information There's a lot there but not exactly what i was looking for. DaveR gave a good burst back in 2001.

My 904 (behind 360) has a TCi valve body but is setup to behave normally. I have adjusted the kickdown levers to how they worked on my 340 with AVS, to give line presssure etc. But no kickdown at low speeds in top gear when i flatten the throttle. My question is... does the kickdown lever (throttle lever i think it's called) on the trans have to hit the end of its travel for the kickdown to work? Or is there just a certain area of travel towards the back where it should work which is dependent on speed/line pressure etc? I ask this because the kickdown is adjusted with this throttle lever held fully forward. I am assuming that the arc of travel of this lever is supposed to approximate the length of travel on the factory carb throttle opening. Which is what i have - a TQ with correct set up kickdown linkage.

The other explanation could be that the TCi valve body doesn't have kickdown provision.

by **burdar** » 20 Jun 2009 15:24

The kickdown lever accually controles the line pressure of the trans. With the lever all the way forward, the trans has minimal line pressure. The farther you push the lever to the rear of the car, the more pressure you get. The trans will only kick-down when the pressure has built up enough to counteract the affects of the gov. on the tailshaft. The lever does NOT have to be at the end of its travel.

I have always adjusted the kick-down by holding the throttle all the way open...push the kick-down lever all the way to the back of the car and lock down the adj. bolt. That gives you full line pressure at full throttle.

I'm not a trans expert but I think if you set it up any differently, you won't be getting the line pressure you need to keep the clutch discs from slipping. The only exception is a full manual valve body but then you don't have any kickdown anyway.

by **Goldenblack440** » 21 Jun 2009 5:04

Thanks for reply Burdar, i'm going out now to have a look at it and will check out those travels. I made the error yesterday of driving it with the carb lever not adjusted properly so that the trans throttle lever was not being pushed right at the beginning of the carb throttle opening. Hope it didn't damage any clutches. I was in such a hurry to drive the thing.

by **fbernard** » 21 Jun 2009 10:19

burdar wrote:The lever does NOT have to be at the end of its travel.

Not entirely true, some transmissions were not progressive and the lever had to be pushed back fully. Other transmissions did have part-throttle kickdown (mostly on slant-6s from what I've read). It was easy to convert to part-throttle though.

http://www.allpar.com/mopar/torqueflite.html

http://www.allpar.com/mopar/transmissio ... -hand.html

by **Goldenblack440** » 21 Jun 2009 11:46

Thanks, not sure if mine has part throttle kick down or not. Although that is possibel if it is a TCI valve body. Anyway, i have kickdown now, so i'm very happy. What the 73 Dodge manual procedure says to do and what the actual linkage is doing in my car are slightly different, so i did something in between. At just a touch off WOT, i made sure the throttle lever on the trans was back almost against the stop. Well, lightly against the stop. Then put the calibration pin in the holes and checked. The manual says it is ijmportant that the lever is held fully forward, but mine is slack, ie,has no spring pressure for the first 1/4 inch of movement so i couldn't get both ends doing what they were supposed to. I opted for that lever being at the start of the spring pressure at throttle rest. Anyway, it drives perfectly now. Maybe it means there will be a touch of line pressure at idle, but i don't think it will cause any dramas? Thanks guys.

by **dave-r** » 21 Jun 2009 14:23

When you adjust it so that the kickdown is all the way back when at WOT you are adjusting it to automatically hold second gear to the highest rpm possible on the adjustment before it shifts up.
This is a good thing for performance. Bad thing for economy. Take your pick. :lol:

by **burdar** » 21 Jun 2009 17:22

dave-r wrote:When you adjust it so that the kickdown is all the way back when at WOT you are adjusting it to automatically hold second gear to the highest rpm possible on the adjustment before it shifts up.
This is a good thing for performance. Bad thing for economy. Take your pick.

The trans should still shift regularly under normal conditions. The gov. on the trans controles the shift points. Under normal driving the line pressure isn't enough to hold the 2-3 shift that high. On my Cordoba drag car it would shift normally,(when I had it on the road) but at full throttle it wouldn't shift until 6100rpm.

by **transman** » 21 Jun 2009 17:24

You might want to check with TCI. If you know what Part Number the valve body is, email them, or see if you can download the instruction manual. TCI may have different settings/setups than what Chrysler had for the stock valve body.
Just a thought. :s023:

transman

by **fbernard** » 22 Jun 2009 8:12

Goldenblack440 wrote: The manual says it is ijmportant that the lever is held fully forward, but mine is slack, ie,has no spring pressure for the first 1/4 inch of movement so i couldn't get both ends doing what they were supposed to. I opted for that lever being at the start of the spring pressure at throttle rest. Anyway, it drives perfectly now. Maybe it means there will be a touch of line pressure at idle, but i don't think it will cause any dramas? Thanks guys.

On a friend's car (onwhich we switched engine and trans last month), a previous owner had added a spring on the kickdown lever (to force it forward on idle), probably for that purpose.

by **dave-r** » 22 Jun 2009 8:18

They are supposed to have a spring on the carb linkage pulling them forward. :confused:

by **Goldenblack440** » 23 Jun 2009 11:03

Yes, that crossed my mind too, to have a spring down there, but then realised what Dave said, the small fine spring on the horizontal kickdown lever does this.

You are right - it shifts a lot higher now in 2-3. 1-2 is the same but under normal acceleration it waits till the speed limit (about 35-40mph) to change, longer when its not fully warmed up. But good to know that i can back it off a touch and it should still kickdown.

My 318 with the factory 2 barrel Holley which has the single linkage kickdown has the same predicament. The single linkage will not let it be adjusted so that the trans throttle lever is all the way back at WOT (Wide Open Throttle)

Transman - tried that!! I tried contacting TCI by phone and email countless times (perhaps 20 times) No response from either! Very frustrating and very poor service. I hope their valve bodies give better service. I only bought the valve body 'cos it was new but going cheap.

by **dave-r** » 23 Jun 2009 11:14

TCI are cheap for a reason.

i.e. crap.

by **transman** » 23 Jun 2009 17:33

If you can, email me the part number of the valve body you've got. I've got contacts at my previous employer that might be able to help.

transman :s002:

by **fbernard** » 24 Jun 2009 12:11

dave-r wrote:They are supposed to have a spring on the carb linkage pulling them forward.

Yes, there's a smaller spring on the linkage, but not all linkage assemblies have one (I've seen a 1973 and a 1970 SB a couple of weeks ago, and the linkages were totally different. One did not have this spring. Both were different from a friend's BB).
The carb linkage might not bring it all the way forward anyway, with the elongated hole in the kickdown throttle rod.

by **dave-r** » 24 Jun 2009 12:29

When the carb is fully open the transmission kickdown lever should just hit its stop fully pushed back.

Then adjust back from this setting till you get nice shifts and can kickdown when you bury the throttle hard.

If there is a gap between the pin on the carb and the back of the slot in the lever it does not matter. What does matter is that the trans lever is held forward with a spring so that it does not fall back.

No Kickdown

No Kickdown 904