Thinking about TH400 kickdown

[dmjlambert]

I have a 1969 CST/10 with 350 and quadrajet. I am thinking about the choices for TH400 kickdown. I rigged up a hand held switch to my transmission and took the truck for a ride to see if my kickdown worked and if I like what it does for the drivability of the truck, and decided I would like to go ahead and hook it up.

For a 1969 truck, it was a carburetor mounted switch like this. I don't have my switch or switch bracket any more, although somewhere in a box I still have the throttle linkage paddle. The switch is flat out not made any more, although I have seen new brackets with throttle linkage paddle for $45. A rusty used bracket and switch like this in untested condition is typically listed on eBay for about $300.


For aftermarket switches there are Lokar and B&M switch kits. I don't care too much for these, but I suppose they get the job done.


There are also micro switches and brackets typically used for nitrous.


There are pedal lever mounted ones that go in the cab for later model trucks that use a throttle cable. This would not work for my truck unless I figured out a way to mount it with a fabricated bracket in the engine compartment.


I am thinking about one of these (below), as it looks really close to the stock design. When I wrote to the vendor and asked about it, they said they didn't have any pictures of it installed, and it is for Pontiacs. They weren't car guys I guess, they were just selling crap on eBay so didn't want to discuss how it might work on a Chevy truck. They are $44.


What do you guys think about these Pontiac fabricated new switch assemblies and the likelihood they would work on my truck? If it won't work, I suppose if I need to I could get the bracket shown in the top picture, and the switch and bracket for Pontiac shown in the bottom picture, and saw off the part of the bracket that has the bolt hole and glue or fasten it to the original style bracket, so I would have the angled metal and hole that holds the switch, and have the right bolt hole mount for the carburetor. I'm considering the options now and interested in opinions.

Or if somebody here on the forum has the fabricating skills to help me out with a stock-like bracket that can hold a micro switch at the right spot, that would be great. If anybody can offer that, then this can be a want-to-buy post.

[bs46488]

I just put B&M switch in my truck with a makeshift bracket I made out of some scrap metal.

Like you said, it does the job. Under the air filter you have to look pretty hard to see the switch.

[FirstOwner69]

When I installed a Vortec crate engine with a Holley in my 69 CST/20, I opted to go with the Lokar switch. I made a very simple bracket for the rear carb stud out of 1" angle aluminum and polished it to enhance the appearance. I then attached the Lokar cable bracket to my new bracket. It all works fine.

The Pontiac switch looks promising depending on the bracket. If you'd like, I can make a tracing of the original switch bracket. It might be a starting point for a bracket for the Pontiac switch.

Here are some pics of my original installed and the Lokar installation. Highlighting on the first picture was for a previous thread. The wire from the Lokar switch to the transmission is not installed in the pic.

[dmjlambert]

Perhaps I'm thinking too much about this, and I should just post a picture and want to buy in the parts section and see if anybody has one to offer. FirstOwner69 is it OK if I use your picture to show what I would like to get?

[FirstOwner69]

Feel free to use the picture.

[HO455]

The problem I see with the Pontiac switch is that it is not sealed and will end up deteriorate internally over time if installed under the hood.

[gator2511]

I just went thru the same thing. I used an Edelbrock bracket & switch. It mounts on the back pass. carb stud. Its small and looks great! Go to Summit and look for part # Edl-72280. It stays out of the way of the throttle linkage and works great. Check it out! They say it can be used for nitrous also but I'm running my TH400 kickdown on it. $38.95

[dmjlambert]

My want-to-buy post was successful, so I'm going to give this a try with the original bracket and switch configuration.