nothing wrong with a 70" driveshaft; the shaft on my '55 chrysler (126" wheelbase) is a single piece unit and is at least that long - maybe longer. How much power are you gonna push thru it? Teh yoke looks like someone ran it thataway based on the lip seal mark about 2" up. As long as the motor is fairly mild (less than 250 HP) you should be fine, but a shorter yoke would be my preference.
I may not reach the bottom but I can sure bang the hell out of the sides!!!.....................seriuosly I think it is not enough for suspension movement another inch and you might be OK. 2 cents.
68/70 chevy 2wd pickups run a 2 piece drive shaft..i`d go to an auto wrecker and try to find one that would be long enough..be a good place to start. you should try to find the correct yoke.
I'm willing to bet the splines are burred from an improper fitment - shine a flashlight in the yoke and examine spline depth; then pull the tailshaft housing off and look at the output shaft. Betcha a little bit of dir grinder de-burring will send the yoke home - and give you the travel you need. bsed on the shiny bits after the paint mark - that yoke went into a trans a lot further than that, originally! If there aren't splines deep in the trans, then yeah - you prolly need a two piece.
why the distaste for a two peice drive shaft? They work great in weird pinioned applications (bags) I plan on running a two peice on my honkin huge 47 buick....
With only 2 1/4" of engagement you have little choice but to run a 2 piece shaft. Even if the suspension travel is only an inch, almost 1/2 of your engegement will be gone. Sure would scare the hell out of me. I also suspect that that yolk is not the right one for that trans, can't imanigne a factory would allow a yolk to have that much leverage on the trans out put bearing. Even with a two piece shaft they figure some movement in case the center bearing trashes out. Most two piece shafts I've seen had short front yolks. Gene
As long as you upgrade the yoke to a slip yoke and make sure you've got a decent carrier bearing. OTHERWISE, you'll just tear the shit out of everything. Tingle Bingle, my Chevy has a two piece, I love it but I don't think I'd just WILLINGLY put it in. They even make a one piece conversion kit. You do the digits yo.
Just incase you change your mind again , back to using this or for future reference. If that yoke is splined all the way to the end, that trans. might need a yoke that has a couple inches of the spline bored out of the inside. Some came this way, which would allow the yoke to slide in further and the counter bore would go over the "wall" at the end of the spline inside the trans. Usually this "wall" would on the other side have a O-ring. The O-ring would seal against the inside of the yoke with the bored out splines, this to help the back of the trans yoke seal out fluid. Also 68" of tube on a one piece driveshaft is maximum with a steel driveshaft. If you find a yoke with the counter bore and it goes in alot further, push it in till it bottoms out then pull it out 1 1/4". Then measure from the center of the U-joint on the trans yoke to the center of the U-joint on the rear. Then deduct about 4", the deduction is for the yokes that get welded in the tube. If this number is 68" or less you are in business for a one piece shaft(steel) or maybe aluminum if you get lucky and find one that has the center to center measurement that you came up with. Remember the further the center of the U-joint is from the back of the trans. it is more likely to give the drive shaft a "whip". Newer vans and trucks run a little longer with aluminum these days. Just thought I would put to use my 13 years of knowlege of working in a driveshaft shop. Hope this helps you or anyone else.
Oh, I forgot to mention that the 68" of tube is with a 3 1/2" or 4" diameter of tube. Not a slim(for that length) 3" or smaller. Yeah Tingler a couple more gears is alot more fun any way.
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