1966 1967 kickdown switch differences

[dsrour]

Thought I would provide my experience converting 66 Eldorado  to 67 quadrajet setup.
Overall pretty straight forward.
The one hang up is kickdown/stator switch.
You will need a 67 switch which are difficult to find and ~$150 for used one.
What I did not realize and have not seen discussed, is the 67 uses a different signal to activate stator at idle.

>The 66 uses brake light signal whereas the 67 uses throttle at idle.
>The 66 switch also is hot in key off
>If you use the 66 wiring as is, with a 67 switch the stator will be activated with key off. Your battery will run down and not good for solenoid
>Changing switch power  to ignition on source, will result in backfeeding of ign on circuits when brake is pedal pressed  with key off
(There is a diode in the brake light wiring of 66, but this is to prevent brake light coming on at mid throttle activation of stator)
What I did:
>remove brake light wire (white) at switch and
>change 12v feed to switched source.
The stator will now work as designed in 67- Stator high angle at idle.
Hope this makes sense

[bcroe]

Thanks, that is good info to know.  Those trans solenoids are definitely NOT
intended for continuous operation. 

Another possible solution is to use a 68 up 2 wire kick down switch and an
electronic controller for the stator, all powered from a 5A fused, ignition
powered circuit.  Bruce Roe

["Cadillac Kid" Greg Surfas 15364]

David,
Just curious.  How does the switch "know" that the car is at idle as opposed to just coasting down a highway hill?
Greg Surfas

[dsrour]

The 67 switch stator terminal is hot at idle thus whenever throttle is at idle the stator will be at high angle. As soon as off idle the solenoid is deactivated until get to second turn on point. It doesn't know if you're stopped or coasting.
I don't notice any difference in driveability  with this setup vs brake light activation. I think the stator blade angle change must be quick.
Another way to solve problem is to modify 67 switch by filing down the part of switch that closes contact at idle, if you don't mind opening switch.
Then it will work w/ brake light

["Cadillac Kid" Greg Surfas 15364]

David,
Just asking.  When I went to a 67 Carb, intake and kick down switch on my 66 I made no other modifications and it worked correctly,  I just checked and the 67 switch I still have and there is no continuity on the stator switch until about mid throttle.  All idle stator operation was through the brake light switch with a diode in the circuit to prevent feedback and kick down when the brakes were applied.  Do you still have the diode in the circuit of your 66?
Greg Surfas

[dsrour]

Hey Greg
The 67 switches I have are all ON stator circuit at idle. The diode is to prevent brake lights from going on at mid throttle stator activation according to 66 manual.
At first I thought my 67 switch was defective, but disassembled and there is indeed a spike like pawl that closes stator circuit at idle.
I then looked at a 67 wiring diagram and there is no brake light feed and switch hot  ign on only.
Maybe someone w/ a 67 could check this
thanks, dave

[dsrour]

Thanks Bruce for your input, I have seen your schematic and algorithm for stator activation using electronics.  Very Clever!
I may go this root at some point.
Dave

[dsrour]

Pictures
switch spindle: arrows show pawl that closes stator switch at idle. You can trim this down a bit so doesn't make contact and use w/ brakelight activation.

67 schematic: arrow shows the second white wire on stator terminal that terminates around ignition points but doesnt look like its hooked up to anything. This would go to brake light switch on 66, you can see diode in circuit that prevent backfeeding brake light.
I'm wondering if this means that they didn't change harness on 67 or there was a design change in production?

[Cadman-iac]

Now I thought that having the brake lights come on when you hit the partial throttle switch activation was to let everyone behind you know that you had just kicked in the afterburner, as you briskly accelerate away, your brake lights aglow through the smoke as if they were aflame, thrusting the car forward in a sudden burst of energy!

After all, wasn't that what the designers had in mind when they were designing these rockets on wheels?

At least that's my story and I'm stickin' with it! LOL!!

[Chuck Swanson]

What is the benefit of going to a '67 carb?  Interesting details on how you got it to work, but seems easier to just rebuild a '66 carb, no?.  I have on 4 Carters on 4 of my 65-66 cars and have no problems, using kickdowns that came with the cars.  Chuck

["Cadillac Kid" Greg Surfas 15364]

Chuck,
Starting off with the numbers, a Carter AFB has a 625 CFM rating and the early Quadrajets are around 750 CFM.  The QJ has the smaller primaries so light throttle results in better fuel economy. Because of the QJ circuitry full range performance was better.
The QJ as used in 1967 absolutely woke up the 429.  I know it did with mine.
Greg Surfas

[67_Eldo]

One fun aspect of using Bruce Roe's switch-pitch controller (at low speed) and a mechanical switch (for 70%+ throttle kick-down action) is that Bruce's controller is, by default, set to switch from high stall to low stall once 10 seconds have elapsed since the last time the brake lights were activated.

There is a slight hill leading up to an intersection near my house. When the light is red, I brake to a stop and then let off the brake pedal. The Eldorado won't roll backward because there's just enough "hill holding" going on to keep the car in place. But if I don't get the green within 10 seconds, the controller shifts the THM 425 into low stall and the Eldorado starts moving forward.

Essentially the car is saying, "Hey! I've waited long enough. Let's get going!" :-)

[bcroe]

One fun aspect of using Bruce Roe's switch-pitch controller (at low speed) and a mechanical switch (for 70%+ throttle kick-down action) is that Bruce's controller is, by default, set to switch from high stall to low stall once 10 seconds have elapsed since the last time the brake lights were activated.

There is a slight hill leading up to an intersection near my house. When the light is red, I brake to a stop and then let off the brake pedal. The Eldorado won't roll backward because there's just enough "hill holding" going on to keep the car in place. But if I don't get the green within 10 seconds, the controller shifts the THM 425 into low stall and the Eldorado starts moving forward.

Essentially the car is saying, "Hey! I've waited long enough. Let's get going!"

Yes that has happened to me.  The assumption is you keep your foot on the brake at
an intersection stop.  But the switch pitch converter is so tight it improves mileage,
but it also wants to creep at a stop until you get it in high stall.  That delay I set to
14 sec, but could be set to 10.  Bruce Roe

[Chuck Swanson]

Chuck,
Starting off with the numbers, a Carter AFB has a 625 CFM rating and the early Quadrajets are around 750 CFM.  The QJ has the smaller primaries so light throttle results in better fuel economy. Because of the QJ circuitry full range performance was better.
The QJ as used in 1967 absolutely woke up the 429.  I know it did with mine.
Greg Surfas

Ahh, good info.  Thanks!  Chuck

[TomB]

I am a proud owner of a deville 67 with a diode on the kickdown switch. However it is not connected. Any suggestion where to connect it to?

thanks,

Tom