Edelbrock micro switch for the Th400 transmissions.

Just found this on the Year One web site. 29.99

If you put an edelbrock carb on your 64, with a Th400 trans, you need the kick down switch to kit the passing gear.

I found this on the Year One web site.  PN. ED72280

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Comment by Farhad on April 20, 2018 at 1:44pm

As always good advice sir! I agree its a cruiser not a roadster. Enjoy your day!

Comment by Tony and Ginny 429 on April 20, 2018 at 12:50pm

You are welcome

As a secondary thought--you really do not want to be --Hammering -the drive shaft in our year cars a lot
The two piece rear section of the drive shaft can be damaged and is a --Big Problem --with very annoying vibration being caused in the drive train
Few shops --have been any good working with our driveshafts and charging a good deal for nothing which adds to the problem
The kick down feature of the trans just puts more stress on a driveshaft that has the potential to cause problems if the drive train is abused ( and not needed in my own opinion )
You have a lot of weight to our cars to add to the drive train stress that takes place

Although our cars have a large displacement engine with adequate HP this is not a car for jack rabbit starts or extensive abuse as that will take its toll on any drivetrain
I suggest a 20 mile an hour roll if you must test it power
This is a powerful Luxury car and should be driven that way
My point being some mistake this car for something it is not
Our cars are simply to heavy to be very high performance cars
Power to weight ratio --always being the key factor when evaluating performance
To summerize - keep you foot out of the carborator ---to extend the life of your drive train

Comment by Farhad on April 20, 2018 at 12:00pm

Thanks Tony! appreciate your input! May just leave it as is then. Thanks!

Comment by Tony and Ginny 429 on April 20, 2018 at 11:08am
The 64 -429 with the turbo 400 trans pulls so strong i had the kick down switch disconnected for years on the stock carb --as i have no need for it
The 64 will get passed anything you need to on the road without it
The kick down - passing gear could possibly be hard on the trans from my own experience in using it a lot in the past on other cars -- and will cause trans damage for the trans long run
The trans damage i have experienced in the past was not with the Turbo 400 but it has made me causious about using that feature a lot
Just my experience and 2 cents on the subject



Comment by Michael Long on April 20, 2018 at 6:43am

I found this on my Chevy website and thought it may help you, good luck!

"Instead of a linkage or cable, the TH400 uses an electrical switch that is most often mounted on the carburetor. The 12-volt connection is a single spade connector just above the oil pan rail on the driver’s side about halfway back–at least that’s where it is on my TH400. When the linkage hits WOT, this completes the circuit to connect the transmission to full system voltage. This electrical input powers up a solenoid in the transmission that accomplishes the same results, with higher line pressure and a signal to downshift the transmission. I simply made a small aluminum plate that mounts to the threaded choke mechanism mounting holes in the carburetor. (Be sure to seal off the small vacuum port on some Holley carburetors that’s used to pull heated air into the choke housing.) Then I mounted the microswitch in such a way that when the primary carb linkage achieves roughly 90-percent throttle opening, the linkage triggers the switch. The microswitch is a relatively common item; NOS sells it under PN 15640NOS. It took about a half-hour to make this bracket and get it aligned properly with the carb linkage. I had to bend the actuator tab a little to make it work, but it has been on my Chevelle for about a year now with no problem."

Looks like beyond that, the package contains instructions as to the location of the wires? One to a "keyed" 12 volt positive connection and the other to the single spade on the transmission.  

Good luck!

Comment by Michael Long on April 20, 2018 at 6:24am

Comment by Farhad on April 20, 2018 at 3:54am

Hi guys! Has anyone installed this? I have the Edelbrock 1411 carb installed but never got around to installing the kick down switch. Can some help me out with how to wire and install this puppy? Any pictures or advice would be much appreciated! Enjoy your day guys!

Comment by Tony and Ginny 429 on September 4, 2015 at 2:42pm
A nice find for those that might miss there passing gear ,after a new Edelbrock carb would be installed
Nice job Russ


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