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Discussion Starter #1
My '63 has a TCI 4 link and I just converted from a 350 turbo to 1971 4 speed Muncie M20. I now have about 3/8" driveshaft clearance at the yoke/trans, and everyone recommends 3/4" to 1". I removed the shocks and moved the rear end up and down and saw very little movement of the yoke in or out of the trans, ao I thought I'd just try it. I broke the motor in and drove the car easy for 20 or 30 miles, but the first time I jumped on it in 2nd and broke the tires loose, it wheel hopped. I'm thinking I may be bottoming the yoke into the trans output and the bind is causing the wheel hop. I plan to have the shaft shortened 1/2". Do you think that might be the issue?
 

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This may help but if you can remove and replace the drive shaft at ride hight it is possibly not the issue. You should check that all the four link bars are the same length pinion angle is TCI spec (1 degree up I think?) and you could move them longer for more driveshaft yoke clearance.

Driveshaft Length
 

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back in the old days it was associated with spring wrap...the rearend wanted to spin with the tires...twisting downward
 

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Discussion Starter #4
Thanks for the advice. I will check the pinion angle. and bar length. I can just barely remove the driveshaft. I'm having it shortened 1/2 inch just to be safe.
 

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you have to have that slop because of bumps...bumps shove the driveshaft in ...holes pull the driveshaft out...with a 4 link there should be NO movement at the rear other than up and down
 

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Not sure if it could cause wheel hop but with the transmission change have you verifyd the transmission angle is correct in relationship to the pinion?
 

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What rear shocks are you using? If they are adjustable, that is where I would start, make a big change and see what happens, then sneak up on it.
 

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Discussion Starter #8
Shocks are the stock ones that come with TCI kit and are not adjustable. It's been super hot here and I haven't felt like going out there and crawling under the car. It's supposed to be cooler this weekend. Once I get my driveshaft back, I will try it again, and then change one thing at a time.
 

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If everything is new, installed, and tuned properly you shouldn’t have a wheel hop problem with a 4 link rear suspension.. Certainly, 3/8” slip yoke travel is cutting it pretty close but 4 links don’t behave like leaf springs so wheel hop wouldn’t be my first thought. I would want to look at engine and transmission mounts and their condition. Another possibility could be chatter in the clutch. What gear ratio is in the differential..? What kind of rear tires are you running..?

I would definitely get the driveshaft shortened to the adequate clearance specs of 3/4-1” range but I don’t think this is the source of your problem..

My '63 has a TCI 4 link and I just converted from a 350 turbo to 1971 4 speed Muncie M20. I now have about 3/8" driveshaft clearance at the yoke/trans, and everyone recommends 3/4" to 1". I removed the shocks and moved the rear end up and down and saw very little movement of the yoke in or out of the trans, ao I thought I'd just try it. I broke the motor in and drove the car easy for 20 or 30 miles, but the first time I jumped on it in 2nd and broke the tires loose, it wheel hopped. I'm thinking I may be bottoming the yoke into the trans output and the bind is causing the wheel hop. I plan to have the shaft shortened 1/2". Do you think that might be the issue?
 

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Discussion Starter #10
The guy at the shop that is shortening it said he didn't think that was it either, but still the right thing to do. 3.90 gear, eurethane motor mounts and stock trans mount. Clutch, pressure plate and flywheel are new, I'm currently running 195/60-14 General Grabber Altimax's. I was off the clutch completely in second gear when it happened. I appreciate the help!
 

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you have coil over shocks correct?...any damp valve adjustment on them?...can you recreate the issue and have someone video it?
 

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I’m not sure which flavor of General Altimax tire you have as Altimax is a line of tires that covers all terrain to touring tire. I’ll assume it’s in the touring catagory and probably not a very soft compound tire that will stick really well under hard acceleration.. Also, the tire size is also quite a small diameter and you’re running 3.90 differential gears which even with a not too powerful small block could probably break them loose.

This video demonstrates axle wrap. Wheel hop occurs when the axle wraps and unloads repeatedly as the tire grabs and breaks free.
 

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My '63 has a TCI 4 link and I just converted from a 350 turbo to 1971 4 speed Muncie M20. I now have about 3/8" driveshaft clearance at the yoke/trans, and everyone recommends 3/4" to 1". I removed the shocks and moved the rear end up and down and saw very little movement of the yoke in or out of the trans, ao I thought I'd just try it. I broke the motor in and drove the car easy for 20 or 30 miles, but the first time I jumped on it in 2nd and broke the tires loose, it wheel hopped. I'm thinking I may be bottoming the yoke into the trans output and the bind is causing the wheel hop. I plan to have the shaft shortened 1/2". Do you think that might be the issue?
If yoke's bottomed out in trans @ jounce , Tran's not long 4 this wrirled.
 

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Discussion Starter #15
I shortened the driveshaft and put it back in. Measured the lengths of 4 link arms and they are all 20 inches. I need to get a level from the hardware store to measure trans/diff angles. I loaned mine out. At least they are cheap. After putting the driveshaft back in, I made a couple hits down the road and no shake so far.
 
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