Thread: TH 400 Kickdown Switch

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I'm finishing up the odds and ends on my '69 C10 and I need to know what to do about a kickdown switch for the Turbo 400. I don't have a factory bracket or switch and the carb is a small OEM 1967 Chevy Holley.

Can anyone point me in the right direction?

Thanks,
Tom

Right or wrong, I decided to go with a switch that B&M makes. My local shop got it for me for around 30 bucks. It comes with brackets, wiring, etc. that will bolt up to the Holley throttle for WOT operation.

I'm sure a lot of guys on the board have also rigged their own at the carb or at the pedal, so you'll likely get a lot of info on this...

I have a silly question here. Why not go to the factory throttle pedal switch from the factory? C series trucks had the 400 tranny in them and even if yours didn't come with that tranny, the switch and set up is too easily available. Just my 2 cents worth.

I use one of these on my Abone with a TH400. Pretty easy to install. Little pricey, but I've seen 'em on eGay used.

http://cgi.ebay.com/ebaymotors/LOKAR...spagenameZWDVW

I found the B&M part but it says to use with a stock throttle cable bracket. I didn't see the kit with bracket on the B&M site. Do you have a part number?

I have every '67-'72 C10 Restoration parts catalog known to man and can't come up with a bracket. NAPA lists an oem switch. I notice that aftermarket throttle cable brackets are different for Holley and Q-Jet and since these engines didn't come with a Holley I'm thinking an aftermarket bracket will be the way I will have to go. I even looked in the Corvette catalogs for late '60s big block with Holley and TH400.

A switch on the pedal would be nice to keep the clutter off of the engine. I may have to do some fabricating.

I'll look at that Lokar too.

Summit lists a Holley bracket for a TH 350, don't know if it'll work for a 400. Part # HLY-20-45

I have the one from Lokar. Spiffy and pricely little bugger. One day I might get it out of the shrink wrap and put it on. My brother in law picked it up for me a while back and was going to put it on when he had my car, but later told me the car was quick enough and if he had installed it, I would probably just kill myself with the accelerator. So it is still in shrink wrap.

Bob...I know what you mean!!!! Since I had 3.73's in the rear, I really didn't think I needed the kickdown cable either. Once I put it on, look out! It really throws you back in the seat when ya push the pedal into passing gear.

Pat

The B&M switch kit says that it mounts to a bracket for a TH 350. I would suppose where the cable mounts. I took a look at that Lokar kit. That would be a clean installation. Not cheap at $67. from Summit but it would be the easiest way out and look the best. My truck has 3.73s too but I'm carrying a little more weight than your A Bone. Gonna need that kickdown.

I wonder about the extra goodies under the hood. Requires trimming, routing, and dealing with asthetics for cleanliness. AMC, and GM ran the foot pedal switch for ever and it would be a much cleaner install that is tucked away and out of sight.

I wonder about the extra goodies under the hood. Requires trimming, routing, and dealing with asthetics for cleanliness. AMC, and GM ran the foot pedal switch for ever and it would be a much cleaner install that is tucked away and out of sight.

If I remember right, the Lokar unit mounts on the trans with only a single cable to the carb and one to the accelerator. Not much in sight to see, mostly under the car. But then again my memory isn't what it used to be and like I said the unit is still in shrink wrap.

Pat - My car only has a 2.73 rear gear (Vette cruiser rear), but unleashing the power from the engine makes the car jump like a rabbit on steriods. Not sure if my heart can take any more thrill or if my reflexes could control it. Maybe one of these days when I need something to do, I'll open the shrinkwrap. If I don't like it, I can always keep my foot out of it.

Originally Posted by 39Deluxe

I'm finishing up the odds and ends on my '69 C10 and I need to know what to do about a kickdown switch for the Turbo 400. I don't have a factory bracket or switch and the carb is a small OEM 1967 Chevy Holley.

Can anyone point me in the right direction?

Thanks,
Tom

I could be wrong here, and if i am please correct me.

I also have a turbo 400. i am using the lokar kickdown box and cable, my kickdown box requires a positive electrical connection, either batt or from ignition, (i forgot which one) that goes to the kickdown box, (which attaches to your trans). From the box it will go to an electrical connection already on your trans. The lokar kickdown still has the cable that attaches to the carb.

I opened up the kickdown box before installing, when the cable is extended all the way, it makes contact with an electrical relay and sends that signal to your trans, i think i remember hearing that the signal operates something in you trans to help fluid flow better when it kicks down.

maybe the ealier 400 trans are mechanical, i dont know, but i didnt see anything mentioned about it

On the Lokar kit that braided cable runs up to the eye on the bottom of the carb lever arm and is secured to a bracket that attaches to the back carb stud. That's all you see under the hood. I like the pedal mounted switch idea too. I'll have to spend some time in my parts books to see what I can find. There must be some kind of linkage and bracket that keeps it away from my big feet and controls the actuation so it doesn't kick own too soon.

Al 400s were electric. My '67 442 had a big ugly rotary switch at the rear of the Q-Jet.

Tom

Well I found the pedal controlled kickdown switch in the parts book. It's still available from GM Parts Direct for under $15. The problem is that I would have to go to the boneyard to find the parts that aren't available. That includes the passenger car style gas pedal asm and the mounting bracket. The application is '71-'75 all passenger cars with THM 400. Since most small blocks and 6s had THM 350s in this time period I'd be looking for big block cars or maybe a rare small block car that someone optioned up to the THM 400 for towing. I'm not sure what the '73-87 trucks used for a gas pedal. I don't have one any more to look at.

Anyway the Lokar is looking better all the time. I could spend more in gas trying to chase down parts that might work than to just online order from Summit.

Don't forget to include G series Vans in your search. Clean install, better clearancing because of the dog house they have to ride next to. I bring this idea forward because a lot of guys don't have much pedal room in their rods with tranny humps and cowl problems. Your '69 should be a snap to find the salvage yard stuff. 1 ton C series included because they share the same assembly.