Overdrive 4 speed linkage

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Early a body

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I have an issue with my 65 dart 318 4 speed. i put in a overdrive transmission about 10 years ago and had to modify the z bar by making it longer so the clutch fork and the z bar would meet up. The issue I was having was the clutch fork does not sit centered in the overdrive bell housing opening . it is almost to the bottom of the bell housing with the transmission installed. Because I lengthened the z bar the pedal is really hard to push down and I am tired of pushing so damn hard. I had to extent the z bar i believe by 1 1/2 inches it get all the linkage to line up properly. Has anyone else experienced this before. What was the solution. I used the clutch fork bracket from brewers an 12 1/2 inch clutch fork and an adapter brewers makes that mounts to the bell housing so the z bar sits level with the z bar mounted to the bracket on the body.
 
If I live long enough, I will go hydraulic, and that is a "turnaround" for me. I used to be "anit" hydraulic. You don't HAVE to use an expensive hydro TO you can fab a bracket and run a slave external to push the fork. I doubt it would fit your 65, but someone markets a nice bracket on here, it sits in the factory pushrod hole and allows the angled mounting of a modern clutch master, l activated by a "stub" pushrod hooked to the stock pedal.
 
I have an issue with my 65 dart 318 4 speed. i put in a overdrive transmission about 10 years ago and had to modify the z bar by making it longer so the clutch fork and the z bar would meet up. The issue I was having was the clutch fork does not sit centered in the overdrive bell housing opening . it is almost to the bottom of the bell housing with the transmission installed. Because I lengthened the z bar the pedal is really hard to push down and I am tired of pushing so damn hard. I had to extent the z bar i believe by 1 1/2 inches it get all the linkage to line up properly. Has anyone else experienced this before. What was the solution. I used the clutch fork bracket from brewers an 12 1/2 inch clutch fork and an adapter brewers makes that mounts to the bell housing so the z bar sits level with the z bar mounted to the bracket on the body.

Did you use all the Brewers 10.5 early A conversion stuff?
 
I bought all the parts from brewers, including the clutch fork, bell housing bracket, The z bar i used a 67-76 a body bracket.
 
Mine was always hard, but I was using a big block factory clutch and pressure plate. Worked great and solved my clutch problems, but it took a man and a boy to press the clutch in. Broke the Z bar tube once and the kludge that I had for the lower clutch adjuster kit more than once. The conversion z bar is different. You might want to check their parts and see if it matches your set up. What pressure plate and disc are you using?

From Brewers Performance: Torque shaft fits 1963-1966 A-body applications when converting to 1968 & later 10.5" bellhousings. Requires use of our BSB636 bellhousing ballstud bracket, AK636 adjusting rod kit, FP484 fork pivot, and CF702 clutch fork..
 
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Mine was always hard, but I was using a big block factory clutch and pressure plate. Worked great and solved my clutch problems, but it took a man and a boy to press the clutch in. Broke the Z bar tube once and the kludge that I had for the lower clutch adjuster kit more than once. The conversion z bar is different. You might want to check their parts and see if it matches your set up. What pressure plate and disc are you using?

Torque shaft fits 1963-1966 A-body applications when converting to 1968 & later 10.5" bellhousings. Requires use of our BSB636 bellhousing ballstud bracket, AK636 adjusting rod kit, FP484 fork pivot, and CF702 clutch fork..
Hydraulic clutch or nowdays a diaphragm or dual disc if you need a lot of grip. I haven't heard of it being done but with the right combo of parts you could probably sneak a dual disc into a 9 1/2" bellhousing.
 
I have one, but If I remember right, 65Cuda273 also tried one and ended up sending it back. So, I'm afraid to try it yet. One day, I'll have time to try all my ideas. I'll try the next clutch when I swap O/D transmissions. I got one from Australia I'm itching to try. I have gone back to the 10 in factory clutch in the 66 but it is slipping in 4th already. Should have just got one from Brewers like you did. I like the factory linkage and the way it feels when right, so will probably never go to hydraulic throw out.
 
I have one, but If I remember right, 65Cuda273 also tried one and ended up sending it back. So, I'm afraid to try it yet. One day, I'll have time to try all my ideas. I'll try the next clutch when I swap O/D transmissions. I got one from Australia I'm itching to try. I have gone back to the 10 in factory clutch in the 66 but it is slipping in 4th already. Should have just got one from Brewers like you did. I like the factory linkage and the way it feels when right, so will probably never go to hydraulic throw out.
Mine sure has been good. My 273 isn't a hot rod though and I don't abuse it. I think a clutch cover full of springs and a different disc and it could stand up to some abuse.
 
I installed an overdrive in a 66 cuda about 25 years ago and the clutch pedal was not hard to push like this set up ended up being. I have since removed the od in the cuda. i took a look at the bell housing i have from the cuda and the fork. i put it onto the engine i am working on and installed the tranny. The fork that was initially in the car that hung low wants to spring down to the bottom of the bell house with the tranny installed. The fork that i had in the cuda wants to spring upwards becoming more centered in the bell housing opening. This may be the reason why the one i was using wants to sit lower in the bell housing. I need to find another z bar and see if it all lines up now.
 
Oh man. I've had this exact problem in my '65 Barracuda after I installed a 360 and the A833 overdrive gearbox with the aluminum 10.5" bell housing. I'm stunned that nobody ever put together the exact right list of bits necessary to make it easy to use. Tons of comments from the usual sellers like "oh, that should work. I guess."

I've had every clutch fork and z-bar combo and tried to make them work. It was always incredibly hard to depress the clutch pedal. I finally went hydraulic and fabbed up a small plate on the firewall to hold a Wilwood master cylinder and then an internal throwout bearing. The hard part is aligning the height of the master cylinder pushrod to bolt to the clutch pedal in exactly the right place. Mine is still too firm, but only half the foot pressure necessary for the best I ever got with a z-bar.

I'm not saying I did it all correctly. But I did spend tons of time and money trying to make it all work with stock or stock-ish parts and finally got fed up. I'd prefer to use an external slave cylinder just in case the internal throwout bearing fails but until recently I didn't have the room because of the headers.

It would be great if someone sold a proper kit or at least a parts list and some measurements of what to make. After all these decades it's still a total PITA.

I dislike automatics but my stupid adventures with all this really make me consider cutting up the tunnel and installing a GM 200-4R.
 
I installed an overdrive in a 66 cuda about 25 years ago and the clutch pedal was not hard to push like this set up ended up being. I have since removed the od in the cuda. i took a look at the bell housing i have from the cuda and the fork. i put it onto the engine i am working on and installed the tranny. The fork that was initially in the car that hung low wants to spring down to the bottom of the bell house with the tranny installed. The fork that i had in the cuda wants to spring upwards becoming more centered in the bell housing opening. This may be the reason why the one i was using wants to sit lower in the bell housing. I need to find another z bar and see if it all lines up now.

AK636 adjusting rod kit, FP484 fork pivot, and CF702 clutch fork
Sounds like you should be sure this is what you are using. Check out the Brewers site.
 
I've never attempted an 833OD into an early A, but let me throw this stupid question out there. Would it not be easier to take a stock early A bell housing to a machine shop, and get the register hole bored out to match the bearing cover on the 833OD? You could then use all of the stock linkage and avoid all of the line up problems if that would work. Chances are, if you're putting an 833OD into something, you won't have an overly hopped up motor anyway. 833OD's never had a reputation for being strong enough to handle much HP.
 
Sounds like you should be sure this is what you are using. Check out the Brewers site.


I used there ball stub bracket for the conversion. However the real issue is the clutch fork did not want to sit centered in the bell housing opening, It wants to sit low, so thats why i modified the z bar to be longer. I had to lengthened the z bar as It was difficult to get the clutch to engage, but the pedal was not tough to depress. I have one of the z bars they make too it is too short due to the clutch fork issue. I had purchased there reconditioned 12 1/2 inch od clutch fork but it sagged more than . I will just play around with it until I get it figured out.
 
I've never attempted an 833OD into an early A, but let me throw this stupid question out there. Would it not be easier to take a stock early A bell housing to a machine shop, and get the register hole bored out to match the bearing cover on the 833OD? You could then use all of the stock linkage and avoid all of the line up problems if that would work. Chances are, if you're putting an 833OD into something, you won't have an overly hopped up motor anyway. 833OD's never had a reputation for being strong enough to handle much HP.

Why ruin a rare early A V8 4 speed bellhousing. The Early A bellhousing is for a 9 1/2 inch clutch, so the best you can do off the shelf is a 10 in scalloped clutch for a six or get the Brewers Performance pressure plate and disc that should hold up. The reason I went to a 71 340 bellhousing was to get a better clutch. The Brewers setup sounds good, and seems similar to the setup in my 64 Barracuda, only done better. The linkage was fine, in my case, it was the HP big block 10.95" pressure plate that was the solution and problem. Best clutch I have had so far, but heavy pressure. OD shifter linkage is different. Early A clutch linkage is different from 67 up A body clutch linkage. My solution was to swap main cases. I get the standard A body pilot diameter plus the cast iron main case is stronger. The O/D is a nice street box for what I want. Don't believe everything you hear, I know of at least one behind a 440 6 pack, but he used a cast iron case also. So far, so good.
 
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My source of manual transmission parts/knowledge is Brewer Performanace.omsite. Great people. IMHO

For these things to work as they should you need the right parts. Sure you can cut/weld a Z bar but it needs to be correct.
 
Ima thinking you have a 6-banger pedal-ratio in that thing.
If so, then you can solve your problem by re-engineering the pedal-ratio at the top of the clutch pedal. This will change your downrod angle and reclock your Z-bar slightly.

Below are the A-body forks; 67 to 76#106R on the left, #702 on the right
the 106 is for a 10.5BH. The 702 is for a 10.0.. You can just make out the repositioned channel for the pivot bracket.

CF106.jpg
CF702.jpg


The 106 is 12.5 long and straight-armed.
the 702 10.875 long and angled backwards.

>below is the 484 bracket on the left, and 680 on the right.
Notice the relationship of the pivot windows to the top bolt. This adjusts the outer end of the fork up or down.
Notice also that the mounting holes are different.
The 484 is the regular, and the 680 is for the early-A


FP484.jpg
FP680.jpg

you can move the forks forwards in the windows by fabricating a spacer and installing it between the bracket and the BH.

Below are the standard 67 to 76, #238 Z-bar on the left, and the early-A #636, on the right. Notice the different positioning of the arms on the tube, and it appears that th 636 has a shorter inboard lever; and possible a longer outboard lever
TS238.jpg
TS636.jpg


all these changes are minor, for fitting the two different clutch sizes, and their bellhousings.
But the pedal-ratio is a major change. I'll see if I can find the Magazine article.
Found it!
Four-Speed A-Body Clutch Pedal Adjustment - Torque Shaft Rod - Mopar Muscle Magazine

 
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^^^ I appreciate all that info!! It is amazing how such minor differences can make the difference in how it all works!!!

A manual trans system that works well is such a joy and one that does not is so bad!!
 
Addition to post 20

Following is a description of how the parts should line up, and some possible solutions to get there.

A) The downrod from the pedal should be horizontally centered/near-centered, in the firewall window,and during use, the downrod should stay in the center portion, vertically speaking. The window is IMO, a generous opening.
The installed Z-bar should end up parallel to the road surface, and at ~90* to the centerline of the vehicle.
So, I'm assuming you have the engine and trans mounted in their factory location. if this is not the case, then you may have to move one or both of the Z-bar pivots, or sub in a different inboard pivot.
So,if/when you get the Z-bar properly located, and the downrod is still not operating properly; then, as a last resort,you might have to alter the window.( I'm also assuming that the pedal is in the factory location.)

B) The TO-fork should be more or less centered vertically in the window, and close to the front edge of it; to allow the use of the already properly engineered Z-bar.
You may need a different TO bearing carrier to get it there, or a different fork-pivot bracket, or even a different fork. But as you can see from the previous post, there are two different forks for the two different Bellhousings, for the two different sized clutches; namely the 10" and the 10.5. Brewers lists the BH casting numbers if you are not sure of which one you have. IIRC, there is one shorter fork(10.5) for the BBs, in the 10.5 BH; but you will lose ratio if you are forced to use it.
After you get that sorted;
The adjusting pushrod should end up about parallel to the road surface, and pushing parallel to the centerline of the vehicle, with the proper Z-bar.

C) If after all this, the pedal is still hard, then you might think about altering the pedal ratio at the top of the pedal. Or subbing in a diaphragm clutch, which is a really low effort deal, even your grand-daughter could operate it. I love mine, on account of it makes idling along at less than 3 mph possible, for extended periods of time..

I hope this helps.
 
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