2 things I learned today

TBP

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Nov 14, 2000
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1. With about $20 in hardware, and 30 minutes of time, you can build yourself a really nice adjustable throttle linkage. :nice: Considering it's really the first time I have ever fabricated a part I am very happy with the results. Anyone who is interested, just let me know and I will forward the details to you.



2. I suck at tuning carbs. :rolleyes: Fortunately I have a buddy with far more experience than me who is going to help me.
 

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steel1212 said:
Lol, thats a nice little device...wait I have one also....but I paid for mine :( I still need to shorten the rod a little more so I have FULL throttle instead of 95% throttle lol.


Out of curiousity, how much did yours cost?
 
skywalker said:
So share, where did you get the parts, dimensions...et cetera.


Here are the parts you will need:
• 1/4" Female-thread Heim Joint (aka. spherical rod end) (2)
• 1/4"-28 Fine Threaded Rod
(2-3ft.)
• 1/4"-28 Hex Jam Nuts (2)
• Insulated Washers #14 (4)
• 1/4"-20 x 1 1/4"Allen screws (4)
• 1/4"-20 Hex Nylon Lock Nuts (4)
• 5/16" Brake Line (12")

This information comes from an old FordMuscle article, that can probably be found online. I just copied and pasted it into a text file. The heim joints are the hard part to find, but with some searching you should be able to find them. I bought mine from here, http://smp.applied.com/base.cfm?page_id=1501

1. The first step is to determine the overall length of the linkage. This length is the distance between the the 1/2" mounting hole in the throttle arm on the carb and the hole in the pedal "bell-crank". To calculate this length, place the accelerator pedal firmly to the floor. Completely open the throttle blades by hand and measure the distance from center of the 1/2" hole in the throttle arm to center of the attaching hole in the pedal arm.

2. Cut the threaded rod 1" less than the distance measured in step 1. This will give you the ability to adjust the linkage about 3/4" shorter than the distance you need, and up to 1 1/2" longer (the rod threads 1" deep into each Heim joint.) Dress the cut end of the threaded rod with a grinding wheel or file to prevent cross threading of the Heim joint.

3. Install the hex nuts (or jam nuts) and Heim joints onto each end of the threaded rod. Ensure the joints are threaded down completely. Cut the 5/16" steel brake line to match the distance from jam nut to jam nut. Remove one end of the Heim joints and jam nuts and slide the brake line over the threaded rod.

4. While the brake line is not necessary, it adds a nice touch. It can be polished up with steel wool, left plain, or painted to taste. Either way the end result is a heavy-duty throttle linkage that functions as well as it looks. It's a wonder why anyone would put up with the factory accelerator rod.

5. The new linkage is intended to mount in the 1/2" upper hole on Holley carburetor throttle arms. A bushing must be used to reduce this hole. The chrome stepped bushings in this photo are available from Moroso and others for about $5. However in a pinch these rubber insulated washers work nicely, and are available for pennies at the hardware store

6. The above mentioned reducer bushings fit into the Holley throttle arm as shown. Use one on each side.

7. Alternatively the insulated washers work well. Use one on either side with the rubber end facing inside the hole.

8. The attaching point at the pedal arm on many early Fords is also 1/2" (with factory plastic bushing removed.) The insulated washers work fine here as well.

9. Use the Allen head screws and nylon-insert lock nuts to secure the rod ends to the mounting points.

10. The easiest way to determine proper throttle linkage length is to set it to manually open the throttle blades completely. Have some one press the accelerator pedal to the floor. Now adjust the rod ends to the line up with the distance between the upper mounting hole in the throttle arm and the mounting hole in the pedal arm.

11. Mounting to the upper hole in the Holley arm upward creates a slight angle on the throttle linkage, giving it leverage to pull the throttle arm over center and ensure complete opening of the throttle blades. The spherical rod bearings prevent binding are allow the rod to be fastened securely. Always use two return springs, ideally pulling in opposite directions to prevent a stuck throttle
 
I like this linkage, but the only problem is that to adjust, you have to take one end off and give it a half turn, so it's really not infinately adjustable. The best is to use left and right hand rod ends and either tap a tube with the correct threads or use a set of dies on a piece of rod (prefered method as it's stiffer) with the correct threads. Now one way that would work, but look a little cheesier would be to use a small turnbuckle and add some jamb nuts to it.
 
1320stang said:
I like this linkage, but the only problem is that to adjust, you have to take one end off and give it a half turn, so it's really not infinately adjustable. The best is to use left and right hand rod ends and either tap a tube with the correct threads or use a set of dies on a piece of rod (prefered method as it's stiffer) with the correct threads. Now one way that would work, but look a little cheesier would be to use a small turnbuckle and add some jamb nuts to it.

Maybe it's not perfect, and I could easily modify it as you suggested. But even to take an end off to adjust would only take 5 minutes max.