Gas Pedal issues on '68
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
Gas Pedal issues on '68
I am having great difficulty getting the stock throttle cable and pedal to have enough travel to fully open the secondaries on my new 950 dfm DP. With the original Quadrajet this was never a problem, it seems as though the Holley based carbs need more cable travel. Has anyone used an aftermarket pedal set-up?
Le Mans Master
Joined: Jan 2006
Posts: 8,319
Likes: 7
From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
I am having great difficulty getting the stock throttle cable and pedal to have enough travel to fully open the secondaries on my new 950 dfm DP. With the original Quadrajet this was never a problem, it seems as though the Holley based carbs need more cable travel. Has anyone used an aftermarket pedal set-up?
Did you use the right cable attach point at the carb? also the check cable accelertor bracket position. lastly it may be that the cable itself has become strached over time?
just a few thoughts
tim
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
Usually, there are multiple holes in the linkage plate on the side of the carb. Measure the amount of cable movement you get when you actuate the accel pedal from full closed to full open. Then actuate the throttle plate on the carb to see if there is a mounting hole on that plate which moves about that same amount [when going from closed throttle to full open]. If there isn't a mounting hole in the proper location for your accel pedal/cable, drill another in the plate where you need it.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
I have tried alternative lower mounting positions for the cable on the throttle arm. Problem is by using the lowest mounting position on the throttle arm the geometry of the cable is adversely affected and the throttle arm will still not open fully. It seems as though I will just have to try and get more 'pull' on the cable at the gas pedal end of the cable. Wondered if aftermarket gas pedal assemblies would fit
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
If the cable is too long you can shorten the gas pedal end like in the pic with a zip tie.You can also remove the pedal assembly and in a vise bend it so you get more stroke before the pedal hits the floor.Lars recommends grabbing the gas pedal and just pulling up and bending it while still in the car-i broke the mount one time by doing it that way and havnt done it since but the mount could have already have been cracked.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
If the cable is too long you can shorten the gas pedal end like in the pic with a zip tie.You can also remove the pedal assembly and in a vise bend it so you get more stroke before the pedal hits the floor.Lars recommends grabbing the gas pedal and just pulling up and bending it while still in the car-i broke the mount one time by doing it that way and havnt done it since but the mount could have already have been cracked.
Yes, I have tried this in the past and (again like you broken the bracket) The inner/outer cable length not an issue (although I have already trimmed-back the outer sleeve) as I am using a CSR billet throttle bracket which gives a good range of adjustment (although it will have to go under a 1" drop base filter base as it won't fit won't fit under stock 2" one).
I have already lost the split grommet thing in your illustration that goes on the end of the cabin-end of the cable. 
I didn't really want to pull out the stock pedal assy as it is a real pita getting there - but I guess its going to the only way. 
Thanks very much for the advise.
Racer
Joined: Jan 2008
Posts: 291
Likes: 15
From: Virginia Beach VA
I'm not 100% sure if this will fix your problem. But I think the 68 pedal assembly was the same as the 69 early version which I had. Here's an excerpt from a previous post of mine where I mostly fixed the problem you are describing...
"There were two different 1969 brackets.... the early one was known to flex excessively when worn (or even when not) because the pivot was two pieces... which usually resulted in the throttle not opening all the way. (I had this same problem)
There are many "Bubba" solutions to this... to include putting a wood block underneath the early pivot point to create more travel and offset the flex in the design...
The later design had a one piece lever assembly (check out Mid America: PN-622-600) and a two piece pivot assembly (a base from Zip: PN- CZ-1071) and then a cover to secure the one piece lever). This "later" design fits the original location and typically fixes all of the pedal flex problems... I could not find the cover anywhere... but it was easy enough to make one out of a metal plate."
Hope you might find this useful
Also here's a link to the original thread: Photo of '69 Accelerator pedal bracket
"There were two different 1969 brackets.... the early one was known to flex excessively when worn (or even when not) because the pivot was two pieces... which usually resulted in the throttle not opening all the way. (I had this same problem)
There are many "Bubba" solutions to this... to include putting a wood block underneath the early pivot point to create more travel and offset the flex in the design...
The later design had a one piece lever assembly (check out Mid America: PN-622-600) and a two piece pivot assembly (a base from Zip: PN- CZ-1071) and then a cover to secure the one piece lever). This "later" design fits the original location and typically fixes all of the pedal flex problems... I could not find the cover anywhere... but it was easy enough to make one out of a metal plate."
Hope you might find this useful
Also here's a link to the original thread: Photo of '69 Accelerator pedal bracket
Last edited by A8skyhawk; Jul 14, 2008 at 03:23 PM.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,527
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From: East London/SW Essex UK
Its 12.45 am here in good old Blighty and I have only just had chance to look at your post. Tomorrow I will look at it in detail. And yes my gas pedal did brake and is 'Bubba'd' (or as we here say 'bodged') together. Thanks very much for detail.
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Former Vendor
Joined: Oct 2007
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From: walpole ma
I had a similar problem with my 68. Due to the extra height of my new intake, and 850 carb,I wasnt getting full throttle. I bought a universal Lokar cable and bracket and it solved my problem. Install the cable,cut it to length and you should be fine
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,527
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From: East London/SW Essex UK
That is another option for me - thanks
Last edited by roscobbc; Jul 15, 2008 at 12:50 PM. Reason: spelling
Intermediate
Joined: Mar 2006
Posts: 35
Likes: 0
From: Dripping Springs TX
Try this--Pull up slightly by hand on the pedal to bend the arm upwards.
The pedal arm is weaker than you would think.
Over time this arm can loose some travel. If you see an improvement bend it slightly more. This worked perfectly on my 68 after I over thought it to death. Got the advise here on the forum.
Good luck!!
The pedal arm is weaker than you would think.
Over time this arm can loose some travel. If you see an improvement bend it slightly more. This worked perfectly on my 68 after I over thought it to death. Got the advise here on the forum.
Good luck!!
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
Try this--Pull up slightly by hand on the pedal to bend the arm upwards.
The pedal arm is weaker than you would think.
Over time this arm can loose some travel. If you see an improvement bend it slightly more. This worked perfectly on my 68 after I over thought it to death. Got the advise here on the forum.
Good luck!!
The pedal arm is weaker than you would think.
Over time this arm can loose some travel. If you see an improvement bend it slightly more. This worked perfectly on my 68 after I over thought it to death. Got the advise here on the forum.
Good luck!!
Racer
Joined: Jan 2008
Posts: 291
Likes: 15
From: Virginia Beach VA
There is also only two bolts holding the whole pedal assembly in place... you could just take the assembly out and do it on a workbench.... it takes about 5 minutes to get it out... however.. bending it will not fix the problem in the long run...
The fact is the two-piece 68 and early 69 pedal lever assembly was poor.. which is why they redesigned it to a one-piece lever in the later 69 models...
The fact is the two-piece 68 and early 69 pedal lever assembly was poor.. which is why they redesigned it to a one-piece lever in the later 69 models...
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
There is also only two bolts holding the whole pedal assembly in place... you could just take the assembly out and do it on a workbench.... it takes about 5 minutes to get it out... however.. bending it will not fix the problem in the long run...
The fact is the two-piece 68 and early 69 pedal lever assembly was poor.. which is why they redesigned it to a one-piece lever in the later 69 models...
The fact is the two-piece 68 and early 69 pedal lever assembly was poor.. which is why they redesigned it to a one-piece lever in the later 69 models...
Which is exactly the reason why I was interested to see if anyone had replaced it with, a Lokar type set-up
Team Owner
Joined: Jul 2001
Posts: 182,997
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From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
The '68 gas pedal design sucks. It wears out and reduces the travel due to the 2 part design..
(Whoever came up with that design should be shot)
I replaced my gas pedal with a Lokar pedal and cable.. No more issues and fully adjustable!
I did have to lower the cable exit (where the cable goes through the firewall) in order to make it work.
(Whoever came up with that design should be shot)
I replaced my gas pedal with a Lokar pedal and cable.. No more issues and fully adjustable!
I did have to lower the cable exit (where the cable goes through the firewall) in order to make it work.
Last edited by GrandSportC3; Jul 16, 2008 at 09:03 AM.
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
The '68 gas pedal design sucks. It wears out and reduces the travel due to the 2 part design..
(Whoever came up with that design should be shot)
I replaced my gas pedal with a Lokar pedal and cable.. No more issues and fully adjustable!
I did have to lower the cable exit (where the cable goes through the firewall) in order to make it work.
(Whoever came up with that design should be shot)
I replaced my gas pedal with a Lokar pedal and cable.. No more issues and fully adjustable!
I did have to lower the cable exit (where the cable goes through the firewall) in order to make it work.
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17