Drilling my Zbar??

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Shmaako

Shmaako

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Clutch does not have enough throw to fully depress my clutch. (Not an original 4 spd car.)
I have pulled my z bar and am planning on drilling a hole 1" down where the pedal attaches to increase the throw.
Any warning or advice before I do?
An on using a hardened bolt with nylon washers.

20210615_164933.jpg


20210615_164717.jpg
 
I thought I read that the Hemi A-Body's had improvements made also, that was in the Jim Schild book. I would not change the torque shaft, you may be doing it several times to get it right. Looks like a Brewers repop shaft for a big block that you have...
 
HemiSSDart said:
I thought I read that the Hemi A-Body's had improvements made also, that was in the Jim Schild book. I would not change the torque shaft, you may be doing it several times to get it right. Looks like a Brewers repop shaft for a big block that you have...
Click to expand...
It is a big block yup. Bought car with it...not sure if it was the proper Z bar but if you say its for a bb then good! Lol
Always sat a little crooked in the car...thinking i may redrill that frame pivot while I'm at it.
 
Shmaako said:
Looks like this clutch rod has been tampered with, (lengthened??)View attachment 1715752026
Click to expand...
Yep, that can be an issue too. The factory big block clutch rod is thicker, that is a small block rod that has been messed with. What bell housing are you using, and if you have the correct one do you have the proper spacer and ball bracket?

101_1828.JPG
 
Here are some measurements I took from a big block z-bar I had. Maybe you can cross check them.
upload_2021-6-15_19-43-7.png
 
HemiSSDart said:
Yep, that can be an issue too. The factory big block clutch rod is thicker, that is a small block rod that has been messed with. What bell housing are you using, and if you have the correct one do you have the proper spacer and ball bracket?

View attachment 1715752064
Click to expand...
Not sure what bell housing I am using or how to identify it either for that matter. I do have a large 1" spacer however, one of the threaded holes is broken so only one large bolt holds the pivot on. I have it solid with locktite and it has not moved while I was using it. I realize it is not ideal but it would require replacing the bellhousing which is not something I want to do right now,(as long as she stays solid.)
 
I take it you are not working with a scatter shield.
Do you know the fly wheel size? If not you can count the ring gear teeth between two clutch cover bolts and multiply by 6.
Is your bell cast iron or aluminum?

Some info here may help also.........
Mopar Transmission Tech | www.darkside.ca
 
Daves69 said:
I take it you are not working with a scatter shield.
Do you know the fly wheel size? If not you can count the ring gear teeth between two clutch cover bolts and multiply by 6.
Is your bell cast iron or aluminum?

Some info here may help also.........
Mopar Transmission Tech | www.darkside.ca
Click to expand...
10.5 130 tooth flywheel
No scatter shield.
Cast...not aluminum
 
After looking into it a bit more the clutch pedal is literally tach welded in place instead of a normal clip! Figures...
Anyway, that makes me wonder if I deal with undoing that and lengthening the clutch pedal to gain the extra throw as described in that article posted above....or drilling a new hole 1" lower in the Z bar arm where the clutch rod connects....
What else can get me the extra throw needed to depress my clutch better??

I guess I can grind off the welds...and jimmy rig something else to keep the pedal in....yeesh..
 
Before you rip and tear, does your pedal system look like the article system?

Shmaako said:
What else can get me the extra throw needed to depress my clutch better??
Click to expand...

Assuming a B&B style cover (3 finger).
Make sure the linkage tight.
Bell crank basically straight across in any view.
Verify your fork pivot isn't bent over, cracked, loose, or severely worn.
Fork tips not worn out or bent.
Re-assemble and work the motion with the pedal while someone watches for deflection or loss motion in the linkage throughout the travel.
Determine if your release bearing length is correct. How far off the fingers does the bearing sit with the pedal up and the fork spring installed?
A refaced flywheel can be spaced back to original position.
A clutch cover finger out of adjustment .040" is another .040" more travel needed to release the disc.
A worn engine thrust bearing can also contribute to travel issues.
 
Daves69 said:
Before you rip and tear, does your pedal system look like the article system?

Definitely looks like the article pedals. But it looks like the previous owner of this car welded the pedal in.

20210614_223643.jpg
After I set the TO super close to the fingers, it still didn't have enough to depress the clutch. The Z bar could be a touch more straight. The motor is newly rebuilt, new clutch, new flywheel. Clutch fork looks worn sure but when I get someone to press the clutch so I can watch, it simply looks like its just too little of throw. Wish I could post the video I have...

Assuming a B&B style cover (3 finger).
Make sure the linkage tight.
Bell crank basically straight across in any view.
Verify your fork pivot isn't bent over, cracked, loose, or severely worn.
Fork tips not worn out or bent.
Re-assemble and work the motion with the pedal while someone watches for deflection or loss motion in the linkage throughout the travel.
Determine if your release bearing length is correct. How far off the fingers does the bearing sit with the pedal up and the fork spring installed?
A refaced flywheel can be spaced back to original position.
A clutch cover finger out of adjustment .040" is another .040" more travel needed to release the disc.
A worn engine thrust bearing can also contribute to travel issues.
Click to expand...
 
Slow down and do your homework. The more you mess around doing it the wrong way , the worse it's going to get. I would start with Post#2 as it is a proven improvement , then go from there . Maybe get the correct clutch rod next. Then maybe investigate Post#8 to see if you have the correct Bracket and spacer and get your Z bar straight. You'll be glad you did it right or if not you may hate it every time you go for a ride .
 
Maybe the positioning of the attachment point on the clutch pedal is jacked. If it is positioned incorrectly, it will affect the overall throw as well.
 
Dan Brewer said:
View attachment 1715752223
Click to expand...
That looks almost exactly as to what I have. Lots of stuff I purchased from Brewers like the zbar bushings, clutch for return spring and the z bar itself I think is from Brewers as well. Not sure if the measurement of the clutch pedal torque rod is the same as mine but all looks the same.
Curious what Brewers thinks about making that 'Hot Rod magazine modification' on the clutch pedal?
I have the BB 10.5 setup..but do not have adequate throw to disengage the clutch enough to get it in gear.
 
I do agree with all the comments made about getting everything "right" first prior to making any mods.
The only thing that is not 100% is the z bar is not perfectly straight from frame pivot to bell pivot. I plan on sliding the frame pivot over to accomplish this but that would mean an oblong hole and not a new hole for the frame pivot. I'm not crazy about that...may need to weld something up.
 
Shmaako said:
That looks almost exactly as to what I have. Lots of stuff I purchased from Brewers like the zbar bushings, clutch for return spring and the z bar itself I think is from Brewers as well. Not sure if the measurement of the clutch pedal torque rod is the same as mine but all looks the same.
Curious what Brewers thinks about making that 'Hot Rod magazine modification' on the clutch pedal?
I have the BB 10.5 setup..but do not have adequate throw to disengage the clutch enough to get it in gear.
Click to expand...
Best to give me a call for tech help, too much to type. Contact info on my website.
 
I have never had a diaphragm cover, but I am having a hard time understanding how the available travel is not releasing the disc based on the relaxed position picture provided.
upload_2021-6-16_10-26-40.png


Is it possible your input shaft is seized in the pilot bushing or bearing? Your clutch cover damaged?
 
Quoted: (A-Body, all you need to do is cut and extend the arm at the rear of the pedal (the arm connected to the torque-shaft connecting arm). If you increase the pin-to-pin length to six inches,) 5 1/4 is stock. Measure yours and see what you have. Anyone know the length on the Brewers ?
 
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