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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
http://im1.shutterfly.com/procserv/4...0Aas2bVk4bt2LA
http://im1.shutterfly.com/procserv/4...0Aas2bVk4bt2LA
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.:LOL: :LOL: 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.:eek: So it is still in shrink wrap.:D
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.
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.Quote:
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.
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. :LOL: :LOL: 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.:eek: :eek:
Quote:
Originally Posted by 39Deluxe
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.
Some top of the line station wagons of the early '60's ran 400 small blocks backed by TH400's. To my knowledge Chevrolet put automatics behind all 400 small blocks. That should help you expand your search.
Even those are getting hard to find in the yards. I haven't found a 400 small block in a long time. The big difference in the pedal that used the pedal mounted switch is in the vertical accerator arm. On late 60s to early 70s passenger cars it's inside the firewall and on trucks it's outside. Not sure about the G van but car stuff would take a lot of work to change. If it ever dries out around here I will have to take a trip to my favorite yards and see what I can find.
Tom
I haven't run into that yet. I think that they just figure that nobody else is stupid enough to buy the junk I take off so it's all profit. :LOL:
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.
One last one.
Hi 39Deluxe I know this is an old thread but I am in need of this brack for my aplacation on my truck can you please send me the templet I whould sure apreciate it thanks in advance.
JulioG, first welcome to the site.
The last posting I see from 39Deluxe was in 2015. You could try to e-mail him directly by clicking on his username (in blue) above and then select "e-mail" member. I'd be amazed if he still had a template from 2009. But you could follow his methodology and make a template from cardboard using the pictures as an example.
I'm still around. I should stop in more though.
The thing with the bracket I made is it is designed to fit the two vertical holes in this Offenhauser 360 degree intake. A different intake would require a different configuration. You might need to use the intake bolts for your bracket. Once you have the switch in hand and a piece of poster board you can judge where the switch will work best and where the mounting legs will need to go down for attachment. It's easy to keep modifying your paper template until you get everything where you want it. You will notice that I mounted the switch slightly high because once the throttle is wide open and the throttle shaft linkage pin rotates forward it also raises to the point that the switch is now inline with the pull. Make sure your steel is thick enough that it doesn't flex under full throttle.
FWIW, what's your opinion of the Offy 360º ?
Well, I've read a lot about them over the years and the theory makes sense. I got a chance to buy this one cheap on Ebay so I did. The engine is fresh. I finished it a couple of years ago but haven't lit a fire in it yet. I want to get it rolling and stopping first. It's a 355 with 9.3:1 compression,1.94 iron heads milled, port matched and street ported, and exhaust ports/chambers polished and cc'd. Cam is a GM Performance 214/224 with .442/.465 lift. My 69 short stepside has a THM400 and 3.73 gears so I expect it to be pretty strong off idle up to 5500 or so. Carb is an original Chevy Holley off of a '66 L79 327 I had restored be Bob Kunz in St. Louis. It will hit cruising speed right in the sweet spot of the cam so everything is well matched.
Don't you run this intake?
Tom
Quote:
Originally Posted by 39Deluxe
I ran it, it's in the garage, on a 400 I had in a 62 1/2ton. Stock 400 with a 650dp and headers and it was fairly stout for what it was. The Offy 360º is a single plane manifold with a split plenum and IMHO it gives you the best of both worlds. I also have it's brother, a dual quad, which I might run on my Vett someday.
I was curious with what you thought of the manifold.