Pontiac GTO Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
38 Posts
Discussion Starter #1
I just notice my throttle cable is frayed on my 1965 GTO (Pictures below) and I don't think it's repairable so it's time to purchase/install a new one.
I checked Ames and OPGI and they list multiple lengths (24" and 36") as well as various housing types.

Any suggestions on which cable I need to order?
Any magic to replacing the existing one (never done it before)?

Thank You!
 

Attachments

·
Registered
Joined
·
38 Posts
Discussion Starter #2 (Edited)
So I ordered the cable (I thought) was the correct part from Franks Pontiac Parts. They asked which model I had (4bbl + automatic transmission).
The cable they sent me was too long (screenshots) and I am thinking that even though I have a 4bbl carb and not the Tripower, I need a shorter cable.

Does anyone know what the correct cable part number from my screenshot is? (or what I should tell the ordering folks)
In my screenshot, cable #1 is what I pulled from the car and cable #2 is what Franks Pontiac Parts sent me as the correct cable for a '65 '389 w/4bbl carb & automatic transmission.
I was able to get cable #2 installed but it had a large amount of bend in the cable and I could not open the throttle completely so it really does not fit.
 

Attachments

·
Registered
Joined
·
3,788 Posts
So I ordered the cable (I thought) was the correct part from Franks Pontiac Parts. They asked which model I had (4bbl + automatic transmission).
The cable they sent me was too long (screenshots) and I am thinking that even though I have a 4bbl carb and not the Tripower, I need a shorter cable.

Does anyone know what the correct cable part number from my screenshot is? (or what I should tell the ordering folks)
In my screenshot, cable #1 is what I pulled from the car and cable [URL=https://www.gtoforum.com/usertag.php?do=list&action=hash&hash=2]#2 [/URL] is what Franks Pontiac Parts sent me as the correct cable for a '65 '389 w/4bbl carb & automatic transmission.
I was able to get cable [URL=https://www.gtoforum.com/usertag.php?do=list&action=hash&hash=2]#2 [/URL] installed but it had a large amount of bend in the cable and I could not open the throttle completely so it really does not fit.


Did the frayed cable work?

The difference I see is the overall casing length and then the cable end that connects to the gas pedal.

My thinking is that I would collapse the cable by pulling on the gas pedal end and measure the distance from the casing to the gas pedal bracket attachment of cable 1 - looks to be about 7". Then collapse the cable on #2 (which looks to be about 9") in the same way, measure #2 from the casing to a point that will give you 7" (go a little more for needed stick-out through the gas pedal attachment end), and cut it.

Then run the cut cable through the gas pedal attachment bracket, and weld, braze, solder an end on the cut cable and draw the cable back through. The new end should be large enough not to pull through the gas pedal bracket end and give you the 7" of length from the cable casing to that bracket as found on the original.

Unless you can send the cable back to Franks' and exchange it, I would first try to modify cable 2 to match the working cable 1 before buying another. The cable casing will be longer, but I can deal with that. The important part is the "pull length" of the cable. You could have 10 feet of cable casing, but it is the cable pull length of approx 7" from extension to retraction (or stop to stop) that is what you are after.

Your carb is also a "universal" carb designed to fit many applications. Edelbrock offers many adapter brackets to make them work with specific car/engine types. It may even be possible to find a different bracket that might change the fulcrum point at the throttle linkage on the carb. https://www.edelbrock.com/catalogsearch/result/?q=+throttle+brackets
 

·
Registered
Joined
·
38 Posts
Discussion Starter #4
Thank you for the quick reply. If I am understanding you correctly, I measured (screenshots) and on the "OLD" cable it was 3 1/4 inches. where the new cable was 3 3/4 inches as shown in my screenshots.
I would then cut the NEW cable to match the 3 1/4 inches of the OLD cable as shown. This would mean that my gas pedal would work the same as it did previously I believe. The fact that I have the extra cable casing along the run won't matter as both cables on the carburetor side fit perfectly.

Please let me know if you think I am misunderstanding or missing a point as you are mentioning a pull length of 7".

On my OLD original cable, I am measuring 3 1/4 inches (i.e. when the gas pedal is NOT touched) on the side of the cable connected to the carburetor. On the inside of the car where the cable connects to the gas pedal I am seeing 3 1/4 inches from the connector that touches the pedal to the part that sticks out of the firewall (i.e. as if the gas pedal is depressed completely). This gives me a 6 1/2 inch stop to stop and not 7" as you recommend.
The new cable is 3 3/4 inches on each side (which equals 7 1/2" total) stop to stop.
 

Attachments

·
Registered
Joined
·
3,788 Posts
Thank you for the quick reply. If I am understanding you correctly, I measured (screenshots) and on the "OLD" cable it was 3 1/4 inches. where the new cable was 3 3/4 inches as shown in my screenshots.
I would then cut the NEW cable to match the 3 1/4 inches of the OLD cable as shown. This would mean that my gas pedal would work the same as it did previously I believe. The fact that I have the extra cable casing along the run won't matter as both cables on the carburetor side fit perfectly.

Please let me know if you think I am misunderstanding or missing a point as you are mentioning a pull length of 7".

On my OLD original cable, I am measuring 3 1/4 inches (i.e. when the gas pedal is NOT touched) on the side of the cable connected to the carburetor. On the inside of the car where the cable connects to the gas pedal I am seeing 3 1/4 inches from the connector that touches the pedal to the part that sticks out of the firewall (i.e. as if the gas pedal is depressed completely). This gives me a 6 1/2 inch stop to stop and not 7" as you recommend.
The new cable is 3 3/4 inches on each side (which equals 7 1/2" total) stop to stop.


Yes, correct. I was looking at the top scale on the tape measure thinking it was inches in your first photos so that was where I got my numbers from.

So maybe there is another solution. 1/2" difference is not much at all. Why not reposition the cable attachment on the carb forward 1/2"? Couldn't you simply drill a new hole 1/2" forward of the attachment point you now have. This would extend out the cable 1/2" more and should take out the slack in the cable. Do a test. Connect it to the pedal, leave the eyelet hook-up at the carb loose, and pull the cable forward towards the front of the car to take the slack out of the cable and see where they eyelet end positions with regards to the carb attachment point.

If you did not want to drill the carb, fabricate a short extension using some 1/8" or 3/16" thick steel. Drill your hole in one end so you can reposition it over the cable attachment bolt you now have. I see 3 nuts under the eyelet end used as spacers - I would leave one as a "spacer" when you attach your extension.

Mark where you need to drill the 2nd hole to connect your eyelet which should be 1/2" away from the end hole you are going to use to attach to the carb. (so you should have 2 holes drilled into the extension approximately 1/2" apart center to center)

Put the length of bolt needed to attach the eyelet end to the extension end first as the head of the bolt might be sandwiched between the carb bracket and extension. Then slip the other end over the original bolt having the 1 nut to be used as a "spacer." This nut will also be sandwiched between the carb bracket and the extension. Once in place, add your nut and tighten the bolt/extension having the spacer. Now you should be able to slip the eyelet end of the cable over the most forward bolt. Add a couple nuts if needed like you originally had to space the eyelet out to get the cable straight. You will want to use a lock nut on the end of the bolt so you don't clamp down too tight on the eyelet seeing it has to move. If that works, I would get a "throttle cable stud" to replace the bolt used for the eyelet which is better and safer. If you Google it, you will see quite a few selections.

So, in a nut shell. You are going to fabricate an extension to take up the difference in the 2 cables which appears to be 1/2". 2 holes will be drilled in your extension 1/2" apart. One hole will attach to the carb bracket hole, the other will have a stud/bolt to attach the eyelet.
 

·
Registered
Joined
·
38 Posts
Discussion Starter #6
Jim... Thank you for all of the great advice. What I ended up doing is a bit easier (for someone like myself without the fabrication skills).
I ordered a set of Odyssey Knarps Cable ends from Amazon for $6. They are usually used on BMX bikes or ATV's as brake or shift line ends: https://www.amazon.com/gp/product/B0017GM1CG/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

Once received, I used a metal file to round the flat ends so it fit inside the horseshoe part that connects to the gas pedal.
NOTE: You need to make sure to align the holes so the cable goes through perfectly straight.

Now I have an adjustable cable and I was able to tune it perfectly (without fabrication to anything inside the engine bay) and the throttle opens fully. My only issue was the extra strands of cable from where I cut it but I believe next time I will put some electrical tape or a ziptie on the cable "BEFORE" I cut it. I have electrical tape on it now but the ends are still frayed inside the tape.

I've included some before/after shots.
 

Attachments

·
Registered
Joined
·
3,788 Posts
Jim... Thank you for all of the great advice. What I ended up doing is a bit easier (for someone like myself without the fabrication skills).
I ordered a set of Odyssey Knarps Cable ends from Amazon for $6. They are usually used on BMX bikes or ATV's as brake or shift line ends: https://www.amazon.com/gp/product/B0017GM1CG/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

Once received, I used a metal file to round the flat ends so it fit inside the horseshoe part that connects to the gas pedal.
NOTE: You need to make sure to align the holes so the cable goes through perfectly straight.

Now I have an adjustable cable and I was able to tune it perfectly (without fabrication to anything inside the engine bay) and the throttle opens fully. My only issue was the extra strands of cable from where I cut it but I believe next time I will put some electrical tape or a ziptie on the cable "BEFORE" I cut it. I have electrical tape on it now but the ends are still frayed inside the tape.

I've included some before/after shots.

Great fix! Thanks for the info link and pics. It may help someone in the future. Instead of electrical tape, maybe solder? or even good old JB Weld. :thumbsup:
 
1 - 7 of 7 Posts
Top