Holley Carb Kickdown Cable

[Carledo]

The Borg Warner box uses a cable operated kickdown which has a very long travel, but only the last half inch actually DOES anything.

That's not true. The last half inch of travel is the bit that operates the kickdown, but all the travel before that raises the internal line pressure to match the throttle opening, without that (say if the cable was disconnected) you are running idle speed line pressure all the way through the range, and that will give slip and judder under wide throttle openings, because there isn't enough pressure to properly clamp the clutches.

Yes, I did correct that earlier statement in later posts, as I know that throttle opening (and therefore kickdown cable tension) affects the trans shift points. I suppose if I had known HOW it does that, I could have reached the conclusion that idle pressure at speed isn't good for the box. But I didn't, which is why I dropped your name into the mix! Thanks for clarifying it!

Hopefully we've all learned something and Tony will now reconnect his Stag kickdown cable and get the adjustment right!

Steve

[Carledo]

I will try your way Steve as i only adjusted it via what the manual said It makes sense what you say. I have had very little to do with auto's in my career as sadly most of my work was fleet, so no more than 3 years old mainly. Boring but the money was good.

Tony.

I tend to leave auto trans problems to specialists too, simply because of my lack of specialised test equipment, which is essential for serious trans work. I did, in my twenties, remove and completely dismantle then rebuild the trans on a 1000cc Mini automatic (3 times in total) aided only by a shop manual and a hatful of ignorance, in a vain attempt to make it go backwards on demand.

This taught me a lot about how an autobox actually works, but the main lesson learned was "know your limits!" Since then, whilst i'm perfectly happy to remove and refit an autobox and know how to change (for example) a torque converter without causing massive damage, I leave anything much more complicated than changing the oil and filter to an expert like Harvey or my local trans guru, Simon at Penn Auto.

Steve

[dollyman]

The Borg Warner box uses a cable operated kickdown which has a very long travel, but only the last half inch actually DOES anything.

That's not true. The last half inch of travel is the bit that operates the kickdown, but all the travel before that raises the internal line pressure to match the throttle opening, without that (say if the cable was disconnected) you are running idle speed line pressure all the way through the range, and that will give slip and judder under wide throttle openings, because there isn't enough pressure to properly clamp the clutches.

Cable reconnected this afternoon but have left a fair amount of slack in it. Will that be ok Harvey? I didn't have any problems with it disconnected, but in fairness i have probably done less than 120miles in it since i did it.
Can you give me an idea of the best way to set it up please Harvey or directions to a something online....... Ideally i would like it to go into top at 35 to 40mph?? Or am i asking to much??

Tony.

[harvey]

The cable shouldn't have any slack in it, but it shouldn't be so tight that it holds the valve open inside the box.

If you think of a towrope between two cars with the rope slack, as the tow car pulls away taking up the slack, there will be a point where there isn't any slack in the rope, but the towed car hasn't moved yet, but it will start to move with any further movement of the tow car. That's the point you're aiming for, and if you hit that sweet spot, the shift points will be as they should be.

[dollyman]

The cable shouldn't have any slack in it, but it shouldn't be so tight that it holds the valve open inside the box.

If you think of a towrope between two cars with the rope slack, as the tow car pulls away taking up the slack, there will be a point where there isn't any slack in the rope, but the towed car hasn't moved yet, but it will start to move with any further movement of the tow car. That's the point you're aiming for, and if you hit that sweet spot, the shift points will be as they should be.

Many thanks for that Harvey, i shall give that a go tomorrow At least it's easy to get to on a Stag. Whilst reconnecting it today i noticed that the cable could possibly be new, certainly very clean.. I don't know a lot about the car as i have not had it long, and there is nothing in history relating to the box.
The oil is nice and clean and doesn't have a "burnt" smell about it.
Thanks again and i will let you all know how i get on.

Tony.

[dollyman]

The cable shouldn't have any slack in it, but it shouldn't be so tight that it holds the valve open inside the box.

If you think of a towrope between two cars with the rope slack, as the tow car pulls away taking up the slack, there will be a point where there isn't any slack in the rope, but the towed car hasn't moved yet, but it will start to move with any further movement of the tow car. That's the point you're aiming for, and if you hit that sweet spot, the shift points will be as they should be.

With the cable having a small amount of slack before the accelerator moves the kickdown, it has transformed the car Harvey On tickover the brass ferule on the inner is touching the outer cable. It has about 3/8 inch of throttle before the inner cable moves..... If i take all the slack out..... it will then change down far to quick for some reason?? Will any damage be caused leaving it like this.

Tony.

[harvey]

With the cable having a small amount of slack before the accelerator moves the kickdown, it has transformed the car Harvey On tickover the brass ferule on the inner is touching the outer cable. It has about 3/8 inch of throttle before the inner cable moves..... If i take all the slack out..... it will then change down far to quick for some reason?? Will any damage be caused leaving it like this.

If the ferrule is crimped on to the inner cable then it could have been crimped on in the wrong position, which I have seen many times. The cable should start moving as soon as the throttle starts to open, if it lags behind, then for any given throttle opening, the pressures will be below what they should be.

[dollyman]

With the cable having a small amount of slack before the accelerator moves the kickdown, it has transformed the car Harvey On tickover the brass ferule on the inner is touching the outer cable. It has about 3/8 inch of throttle before the inner cable moves..... If i take all the slack out..... it will then change down far to quick for some reason?? Will any damage be caused leaving it like this.

If the ferrule is crimped on to the inner cable then it could have been crimped on in the wrong position, which I have seen many times. The cable should start moving as soon as the throttle starts to open, if it lags behind, then for any given throttle opening, the pressures will be below what they should be.

Do you think it will damage anything Harvey or is it ok to keep driving it? Or should i remove the ferule? It's not a daily driver by the way. Really appreciate your help. Are you local to Cheshire by any chance, as i would willingly pay you to set it up.

Tony.

[harvey]

Do you think it will damage anything Harvey or is it ok to keep driving it? Or should i remove the ferule? It's not a daily driver by the way. Really appreciate your help. Are you local to Cheshire by any chance, as i would willingly pay you to set it up.

The first thing I would ask is, as it is now, if you come to a stop on a closed throttle after driving do you experience a "clonk" on the 2-1 downshift? if you do, as you have slack in the cable above the crimp, then the crimp must be holding the cable too tight, which is holding the valve open a bit, in which case the crimp needs to be either removed, or made to slide freely on the cable.

I'm a good way away from Cheshire I'm afraid, although not too far for some people as a guy from Cheshire brought his P5B down for a ZF conversion a few years back. Regardless of all that though, I'm quite happily retired now.

[dollyman]

Do you think it will damage anything Harvey or is it ok to keep driving it? Or should i remove the ferule? It's not a daily driver by the way. Really appreciate your help. Are you local to Cheshire by any chance, as i would willingly pay you to set it up.

The first thing I would ask is, as it is now, if you come to a stop on a closed throttle after driving do you experience a "clonk" on the 2-1 downshift? if you do, as you have slack in the cable above the crimp, then the crimp must be holding the cable too tight, which is holding the valve open a bit, in which case the crimp needs to be either removed, or made to slide freely on the cable.

I'm a good way away from Cheshire I'm afraid, although not too far for some people as a guy from Cheshire brought his P5B down for a ZF conversion a few years back. Regardless of all that though, I'm quite happily retired now.

I didn't notice any "clonk" Harvey, but i wasn't looking for it. It "clonks" slightly going from reverse into drive and back, but my other two cars do the same. I will give it another go tomorrow morning. I don't blame you for retiring completely, i have done the same more on health grounds though.
Will report back tomorrow and thanks again.

Tony.

[dollyman]

Harvey, i can't thank you enough the gearbox is performing perfectly now A bit more adjustment today and it changes up, down goes through the gears great.

Tony.

[new to this]

Harvey, i can't thank you enough the gearbox is performing perfectly now A bit more adjustment today and it changes up, down goes through the gears great.

Tony.

Tony

now watch out for those speeding tickets

[dollyman]

Harvey, i can't thank you enough the gearbox is performing perfectly now A bit more adjustment today and it changes up, down goes through the gears great.

Tony.

Tony

now watch out for those speeding tickets

I hope not Dave, but the van's are rife around here at the moment

Tony.

[new to this]

Harvey, i can't thank you enough the gearbox is performing perfectly now A bit more adjustment today and it changes up, down goes through the gears great.

Tony.

Tony

now watch out for those speeding tickets

I hope not Dave, but the van's are rife around here at the moment

Tony.

Tony

what colour is your car, they seam to pick on white / silver vans

[dollyman]

British racing green Dave, but my Dolly is white I will have to keep my eyes peeled I have been trying to post a pic, but i will have try and shrink a photo.

Tony.