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Discussion Starter #1
It seems that the lurching while starting out with my Edelbrock Pro-Flo 4 setup is due at least in part how the engine torques changing the throttle position when letting off the clutch with the throttle rod. I'm not going off on that conversation other than saying it's a "thing" and has apparently also affected forum member @indyphil when he went from auto to manual on his 68 along with other makes and models with throttle rods.

The Lokar cable pedal assembly is expensive, concentrates 100% of the load at the small hole that goes through the firewall causing it to flex, and is unnecessarily cool for something that will never be seen. The Lokar setup adds up at $300 real quick after you include the cable and bracket. A 69 cable throttle pedal assembly can be had from our "friend" Scott Drake for $70 with another $30 needed for a universal cable. I've searched and found vague references that it can be done on some years of Mustangs but what about 65's? If anybody on the forum has done it or can find any info on the swap please respond!
 

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1968 Mustang coupe, 331 engine
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Id love to know more about non-Lokar cable throttles - so thanks for the mention. I actually tried a lokar a while back just because I thought it would be better than the wobbly old throttle linkage and - at least in my experience found the Lokar design to be subpar. The main pivot bushing was plastic and not well made, the whole thing mounted to a flimsy part of the firewall, and worst of all the top lever arm that pulls the cable moved through an arc, so at either end of the pedal movement the cable was in a bind with its housing, in fact the cable drag from this set up was really bad, requiring a heavy return spring and leaving the pedal feeling really "sticky". Im currently thinking about a drive by wire setup, but its complicated, id need a late model pedal, some kind of servo actuator and a control module complete with a driver to control the servo.
Im also installing traction bars and subframe connectors soon, but I suspect this wont help if engine torquing is the main problem. I dont want solid motor mounts either (Im not a fan of solid mounts, I dont like racecar vibrations and noise)
As a bonus Id like a pedal that doesnt hinge in the middle of the pedal pad like the old OEM pedal in my 68. I prefer a modern hanging pedal with a slight convex shape.
 

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1968 Mustang coupe, 331 engine
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ive ordered a 69 pedal, universal cable and the cable bracket, we will see how it goes soon.
 
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I read that post and thats where I got the idea.
I just finished installing a tinman fabrications subframe connector and traction bar combo. It "improved" things by - maybe 10% or maybe its placebo. I definitely enjoy the stiffer car, which is very noticeable, it rides and drives like a more modern car and more confidence inspiring instead of like fear inducing wet noodle.
So the 69 throttle pedal assembly arrives in the mail today, I have the cable and bracket already. I took a small underhood video while driving and it did seem as though the engine was rocking and making the throttle open even more than my foot intended, so Im fairly confident the cable upgrade will help, it may also add a little drag which should help. I took my daughter for a ride and its weird because I can totally drive it 100% without a problem, but if I want to induce the lurching Its really quite easy to do that too.
If the cable doesnt fix it then Ive decided I will fabricate something like this for the throttle shaft.
 
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It’s kind of funny as I was looking at that last week..What’s the difference between 69 and 70?
I think this is the way to go and get rid of all that metal linkage..
Any though on using a 69/70 emergency brake pedal assembly?
 

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So I got it installed tonight. I used a russel cable bracket at the throttle body and I had to do a little fabrication to make it work nicely. I'm a stickler for making cables exit smoothly and no drag at weird angles and so I had to customize it a bit. I used a cheap universal cable from ebay and it had a kind of Clevis end on it. I pulled the cable out and made a little bit of bar stock to go in the 69 pedal. The 69 pedal mounted OK but drilling the larger hold for the cable end was a huge pain. Also the stuff in that other post about using one of the original mounting holes didnt work for me. I found it made the pedal too high up compared to the original. In any case I positioned it where I wanted it.
I've attached a couple of pics here but the best part was the test drive.

The positive feedback loop from the engine twisting and the solid linkage was gone. This made the car much easier to drive smoothly. I found the pedal ratio to be a little faster than the original which I can try to fine tune with a little work on the throttle shaft (I may add a flat plate and a hole or I may just make a whole new throttle arm) but for now it works really well. My teenage stepson was able to drive it and only made it lurch a little when he shifted into 2nd and goosed the gas a bit too much. To be fair to him hes learning to drive stick in a 3000lb car with almost 450hp, low gearing and a bunch of grip, she is a twitchy thing compared to your average fleet/rental car.
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Discussion Starter #9
Thanks for the pictures! I know what I’m doing next weekend. I’m just going to make my own bracket for the throttle body.
 
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So I couldnt leave well enough alone. I took my old engine block plate from the automatic trans and used it as scrap steel (I know the horror!) I then cut it in a circle and welded on a small piece of steel brake line. I then worked it with the grinder and cut off wheel, measured and drilled and made the pulley in the photo. Now off idle it pulls from a radius of 50mm instead of 35mm. The pedal travel is the same. I have a little finesse work, paint etc... and I need yet another ebay cable kit to finish it but it should be 30% less sensitive off idle, and progressively speeds up to achieve full throttle in the same pedal travel as before. A billet aluminum version could be a nice seller for edelbrock. Could even make it with different pulls and ratios
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Discussion Starter #12
So I couldnt leave well enough alone. I took my old engine block plate from the automatic trans and used it as scrap steel (I know the horror!) I then cut it in a circle and welded on a small piece of steel brake line. I then worked it with the grinder and cut off wheel, measured and drilled and made the pulley in the photo. Now off idle it pulls from a radius of 50mm instead of 35mm. The pedal travel is the same. I have a little finesse work, paint etc... and I need yet another ebay cable kit to finish it but it should be 30% less sensitive off idle, and progressively speeds up to achieve full throttle in the same pedal travel as before. A billet aluminum version could be a nice seller for edelbrock. Could even make it with different pulls and ratios
I like the way you're thinking with the progressive linkage! Many of my spinouts at autocross are always driver error but were aided by the touchy throttle response even with the FiTech. If you come up with something that works I might be able to reproduce it out of 3/8 plate aluminum and various router bits. Aluminum plate is softer than a lot of hard woods and engineered materials I work with daily.

I found a few hours to start my installation today. I did a lot of measuring before I started so I knew were the original throttle pedal was located. For me the upper hole ended up directly in-between one of the upper and lower holes from the original bracket.
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Instead of trying to replicate the original style cable to pedal mount the indyphil did so well I just spent some time filling the original cable end location to work with my Lokar cable.

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After the second trial fit the holes I had drilled in the firewall were stripped so it was 1/4" nutsert time. Probably better in the long run as it would have failed at the track eventually. That is one super thin firewall!
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My back is junk and I'll be paying for this under dash adventure for at least a week or two. A yes I removed the seat before I even started. I'll fab the throttle body bracket at work this week. I'm going to loop the expensive Lokar cable instead of cutting until I find out what indyphil comes up with on the progressive linkage.
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I've finished my pulley cam thingy. Went for a drive and it works great. I do have some electrical problems though so I'm down until I find what's going on. Heres a pic of the painted/installed cam
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In other news I'm making a custom pedal and pedal cover. Lol
 

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I like your progressive linkage, is there any specs you can give on it? How do you know what arc to put on it to get the proper progressive feel but still go full throttle?
 

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I worked it all out by making a 1:1 scale drawing and figuring out the rough cable pull with a bit of math (pi times diameter = circumference of a circle). The trick was to cut out a circle but then mount it off center. I'd like to replace it with a machined aluminum part, instead of my hacked together thing so I may end up modeling one up and ordering from an online machine shop
 

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I put a 69 pedal assembly in a previous '66 of mine....but that was over 10 years ago on a car I have since sold and can't remember the details....but it was not difficult. That being said, just like the Lokar setup, it also puts all the pressure on the firewall....but unlike the Lokar setup, it also leaves a big hole to plug...and when you consider you will likely spend $50 for a '69 pedal, the Lokar setup isnt THAT much more expensive, and it is far nicer and smoother operating. In other words...retrofitting a 69 pedal isnt gaining you much....take it from someone who has used both options on different cars.
 

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But does the pedal look factory or is it then mismatched? I would go '69 just based on that IMO

Chris
 

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Discussion Starter #19 (Edited)
I put a 69 pedal assembly in a previous '66 of mine....but that was over 10 years ago on a car I have since sold and can't remember the details....but it was not difficult. That being said, just like the Lokar setup, it also puts all the pressure on the firewall....but unlike the Lokar setup, it also leaves a big hole to plug...and when you consider you will likely spend $50 for a '69 pedal, the Lokar setup isnt THAT much more expensive, and it is far nicer and smoother operating. In other words...retrofitting a 69 pedal isnt gaining you much....take it from someone who has used both options on different cars.
The 1969 pedal is $72 new and is made in the USA. The Lokar pedal is currently $197 also made in the USA. You still have to buy the cable with either pedal. I bought the $50 Lokar cable because it had no plastic fittings and was made here.
 

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The 1969 pedal is $72 new and is made in the USA. The Lokar pedal is currently $197 also made in the USA. You still have to buy the cable with either pedal. I bought the $50 Lokar cable because it had no plastic fittings and was made here.
Really? I could have sworn the Lokar pedal was $120-ish when I bought it, but maybe I am remembering wrong. As for the throttle cable...the Mr-Gasket cables fits the Lokar pedal(or any other I guess) just fine with all metal parts for $25(well, sleeve I guess is plastic, but better that than braided). You can also swap the stock pedal pad onto the Lokar pedal simply by drilling one side of the mounting holes bigger if that is a worry.
 
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