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-   -   Holley Throttle Cable Bracket Issue (http://www.hotrodders.com/forum/holley-throttle-cable-bracket-issue-184482.html)

Pre-Tuner 09-14-2010 08:59 PM

Holley Throttle Cable Bracket Issue
 
I bought this Holley Throttle Cable Bracket:

http://www.summitracing.com/parts/HLY-20-112/

If I leave both springs on it, it is really difficult to press the throttle down. It's difficult enough that it would affect my reaction time. I would imagine there is also increased wear on the carb throttle shaft bore.

If I remove one of the springs, the pedal feels good, but it doesn't quite pull the linkage back enough and my idle RPMs run too high.

Any ideas of what to do?

My Dad suggested that I ditch it and just use a spring, but I'd rather not since it wasn't cheap and it holds my TV cable also. I know there are other brackets that will do the same thing, but I already have this one.

ericnova72 09-14-2010 09:26 PM

Looks to me like the springs pull from the front, opposite of the cable?? If so it is what you want, it will not wear the throttle shaft this way. If the springs pull from the rear, just like the cable, but pulls on the lower half of the throttle lever, then it is the bad configuration and leads to more wear on the throttle shaft bores as both cable and springs are pulling to the rear wearing the back side of the throttle shaft bores.

Double springs are mandatory for track use, it is in the rule book. If it seems especially stiff it may be a worn throttle cable that is tight (or binding under pressure) in the casing, otherwise you need to exercise that foot!! I fail to see how this will affect reaction times unless you have a really, really weak ankle.

Pre-Tuner 09-14-2010 09:36 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.

Thanks.

Pre-Tuner 10-04-2010 08:54 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?

bubbahotep 10-04-2010 09:18 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.

http://www.hotrodders.com/gallery/da...m/p9290108.jpg

Pre-Tuner 10-04-2010 09:35 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.

http://i64.photobucket.com/albums/h1...h/HPIM0303.jpg

Landshark928 10-04-2010 09:58 PM

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.

Pre-Tuner 10-04-2010 10:18 PM

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.

bubbahotep 10-05-2010 12:47 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

ericnova72 10-05-2010 01:14 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.

bubbahotep 10-05-2010 01:30 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

malc 10-06-2010 01:19 AM

Moroso do a throttle return spring kit includes heavy and light sets of stainless steel return springs.

Pre-Tuner 10-06-2010 09:30 PM

I saw those. For $7, I might put them on my next Summit order just to try them.

cobalt327 10-07-2010 07:36 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. :D 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. :(

http://www.hotrodders.com/gallery/da...PRINGS_002.jpg

Pre-Tuner 10-07-2010 06:36 PM

Cool, I'll just swing by. GA isn't too far from WA.


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