Thread: TH 400 Kickdown Switch

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It's been awhile a since I updated this thread and I work slowly but tonight I got it in gear and made the parts I needed. I bought a B&M switch kit from Summit. It is a pull on switch with the parts to connect it to the Holley throttle arm. It still requires a bracket on the carb or intake so I made one. Now I can use the stock wiring ro connect to the trans and it was a lot cheaper than the Lokar cable deal.

First thing I did was get familiar with how the switch worked. It has a rod that pulls on a spring that pulls the switch on. It is supposed to be full on a little before the carb is wide open. The spring allows the carb to go wide open after the switch is all the way out. The rod is adjustable so the bracket can be close and be good enough.

Next I measured and triple checked my sketch to be sure things would line up. I found that the switch needs to be mounted higher than the carb linkage so the rod will be pulling near horizonally at wide open. Now I transferred my measurements to poster board. Bending the poster board to shape showed me how the bracket would fit.

Then I cut out the 1/8 steel to shape, bent the tabs and drilled the holes. I was amazed that the bolt holes on the manifold actually lined up perfect. We all know how that usually goes.

The attached pictures show the bracket in process and the whole thing mounted and adjusted. Now I need to take it off to clean it up and paint it.