|10-08-2010 11:28 PM|
I usually run one spring forward and one from the bottom back, it centers the shaft and makes it float, also doesn't wear out the bushing.
|10-08-2010 10:52 PM|
Ok, got 'er fixed.
Same springs...both of them. The way I figured, the spring holder on the carb had more leverage that the cable did where it was mounted. Moving the spring holder or springs was not an option, so I knew I couldn't move them down to where the throttle cable was. So, I decided to move the throttle cable to the spring mount where the huge half-inch hole is in the carb linkage.
I wanted to do this initially, but the throttle cable/pedal assembly wouldn't allow me to. I did some investigating and there was a small pressed on stop that was preventing me from being able to pull the cable out enough to attach it to the carb without opening the throttle blades and still have enough throw for wide open throttle. It was only about an eighth inch away from working, so I cut the stop off and it created enough slack to mount to the carb.
One other thing I noticed is how crappy the design is for the spring mount. Bolted together the way it is intended, there is about a sixteenth of an inch of play side to side, so the spring holder is really loose, which causes it to bind in the hole. The hole in the carb looks like it was pressed, so the outside of the hole is pretty course, which only adds to the binding force. My repair for this was to add some very thin shims to each side of the mount to take up the slack. The only shims I own were exactly what I needed, though I can't remember what the hell they were for originally. Cam button maybe.
After all of this I got in it with both springs pulled all the way back (heavy tension at rest) and pressed the pedal. That thing is so smooth now I couldn't believe it. It is as smooth as it was when the truck was TBI if not smoother. I had the wife come out so I could verify WOT and it seems to run out of throw exactly where it needs to. This should make it a lot more fun to drive.
Here is a picture of what I have now.
|10-07-2010 07:36 PM|
|Pre-Tuner||Cool, I'll just swing by. GA isn't too far from WA.|
|10-07-2010 08:36 AM|
That bracket/spring assembly looks tuff, but those extension springs are not what's needed in this application- they look to me to be too large of a diameter wire, but too small overall diameter, and will be stiff as heck, most likely.
Instead, what you need is a smaller wire, larger overall diameter spring, w/another spring running through the larger spring's ID- just as the factory does it. Unfortunately, that'll leave the bracket w/an empty spring position- unless you found a pair of single springs made like I mentioned, that were small enough to work in tandem. Shouldn't be a difficult thing to find, but I don't know how much OD you can use before the spring would begin to rub on the bracket- and you do not want that. Not because it'll scratch he anodised bracket, but because the spring cannot have contact on anything that'll wear on it or cause friction to the spring's action.
Anyway, swing on by my house after work. I'm pretty sure we can come up w/something that'll work just fine. It will not (and should not) be chrome plated, though. Chrome plated springs are for show cars and trailer queens, IMHO. They also shouldn't be rusty, as a couple of mine appear to be.
|10-06-2010 10:30 PM|
|Pre-Tuner||I saw those. For $7, I might put them on my next Summit order just to try them.|
|10-06-2010 02:19 AM|
|malc||Moroso do a throttle return spring kit includes heavy and light sets of stainless steel return springs.|
|10-05-2010 02:30 PM|
Eric, as I was saying....I'll be removing my 2" bolt from the rear and getting my spring back up front
Doh, totally overlooked that problem. Good lookin out
|10-05-2010 02:14 PM|
Bubbahotep, lots of people do it the way you have in some form, along with GM does it the same way, but there is a problem with this. The spring is pulling to the rear, and the throttle cable is pulling to the rear....which wears like you wouldn't believe on the throttle shaft bores in the carb because all forces are put against the rear side of the shaft hole.
This is the reason you practically can't find a Quadrajet that dousn't have the throttle shaft bores in the baseplate all wore egg shaped and leaking vacuum. If you look at the direction they are worn, it is plain to see why.
|10-05-2010 01:47 PM|
I have a 200r4, funny my problems were the same. The pretty aluminum spring arm (way on top of the rotating throttle blade linkage) is just too high. The springs get so stretched due to the amount of leverage.
I have my spring (just 1) on the bottom side of the carb base plate and tied to the REAR of that red linkage setup. Instead of pulling towards the nose of the car I'm pulling to the rear but the spring is on the bottom .....which pulls the plates closed. Very soft now. Follow me?
I put a 2" bolt down through the square throttle mounting point is and hooked the spring to the end of the bolt. Wish I had a pic. My spring is about 2" below that entire bracket, at the rear, and under my throttle line
|10-04-2010 11:18 PM|
|Pre-Tuner||Right now, I have it moved just enough so that there is tension on the springs. There is really little pull on the springs at rest.|
|10-04-2010 10:58 PM|
|Landshark928||Just based on the picture you have a good bit of play in the spring bracket slot. Is it all the way forward now? Moving it towards the carb reduces tension. Otherwise find new softer springs.|
|10-04-2010 10:35 PM|
I think I am already using that hole. I have a 700R4 transmission and it required a special bracket. I installed the throttle stud in the upper hole in the bracket.
Here's a bad picture of it (sort of). The bracket is installed with a bolt in this picture before I realized I didn't have a place for the cable to connect. I believe I am using the same hole you are.
|10-04-2010 10:18 PM|
I have the same bracket and found the identical issue. The thing, in my opinion, is designed wrong for certain applications
My problem, which might not be yours: The hole you use as the leverage point is wrong. You might notice that you can EVER get wide open throttle because you're eventually pulled full, and then trying to pull down.
Sometimes they mount the throttle holder piece under the bracket so that the linkage is going "up" on an angle.
I almost had to do that but used a different hole on my holley carb. Worked good but really needs a good pedal push to make WOT. Its not the spring, its the physics of it
I added this image. You can see the OLD hole not used was higher up, too high to work. Please disregard my ugly idle mixture screw which I locked in place with gray silicone.
|10-04-2010 09:54 PM|
Ok, I bought a new cable, installed the second spring again, and that damn thing is every bit as hard to push down as it was before.
The pedal moves very freely with the cable disconnected, so there is nothing going on there.
I'm not exactly a small dude, so it concerns me a little that it takes so much effort to push the pedal down. One spring is not quite enough to get the job done, so I think I may try and source either a single stronger spring or two weaker springs. I don't know what else to do.
Is it possible that a pedal used for TBI has a different leverage point than one that would be used with a carb?
|09-14-2010 10:36 PM|
I figured with the cable fighting one way and the springs fighting the other it would wear in the middle where the fulcrum was, but what you say makes complete sense.
Maybe I'll start by replacing the cable and see what that does for me.
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