why do you think that your situation might not be standard ? Did you modify the rear end or engine position ??

 

The distance from the face of the tail shaft to the CL of the U-Joint is a function of shaft length. A distance of 3" is considered to be the maximum. So even with a 26 5/8" shaft, I will be at 3". Now, I am at 3-1/8". I would prefer to be inside the maximum dimension if possible. The larger 1330 yoke body will mean a reduction in the amount of exposed shaft only. I don't know if my situation is non-standard. Maybe that is how all 1972 C3's are. I was hoping to get some guidance from Richard.

 

Keith:
The 3" measurement IS the optimum distance for a driveshaft. On a vette, with the fixed rear end, there is virtually no movement in and out of the slip yoke so we can build them longer. With a 26 5/8" shaft and a 1330 yoke, you will get 3" from the tail to the center of the front u-joint.
I am not asking you to pay anything for the driveshaft, only the upgrade for the bigger yoke. The advantage with going with a crossover u-joint is the weld yoke will be smaller on the tube which will help with the clearance in the tunnel. Your power output(as stated) will not break the FRONT joint. The shock load hits the rear joint first and then is transmitted to the front. The rear will take the beating, not the front.
Once again, just to clarify, 3" is the norm for the measurement. Anything less(longer shaft) you run the risk of jamming the yoke into the trans under "rap up". Anything more, you run the risk of sliding the yoke out of the output. Again, on a vette(yours in question), the rear end is fixed and the above statement doesn't apply.
The bottom line, if you don't want to go with a crossover, I'll need your driveshaft back and $99.00 and I can set you up with the larger yoke. Let me know

Richard

 

Richard,
If I had a 26 5/8" long shaft, I would probably take you up on your cross over offer.

If I had originally requested a shaft with a 1330 front yoke, would there have been a $99.00 up-charge for that?

 

YES. Technically, it would have been $139.00. I was giving it to you at cost($99.00).
Did you not say yours was 26 5/8"? How long is your d/s? Actually now I think about it, you said 26 1/2". I promise you 1/8" is not going to make ANY difference on a vette. Again, let me know.

Richard

 

Richard,
Yes, my shaft is 26 1/2"

If 3 1/8" is ok then why do you normally supply 27 3/8" long shafts with the 1310 yokes?

Based on what you are saying, it would appear my 26 1/2" long shaft will work fine with my 1310 yoke even though it extends out from the tail shaft the amount shown in my posted photo.

What is the benefit of going with the cross over yoke then?

 

The 1310 yoke is not as long as the 1330 yoke that's why we use a longer driveshaft with the 1310 yokes.
The benefit to a crossover joint, in your case, is that you wanted the larger yoke in the front. You already have the correct length for use with the larger yoke and joint, that's why I suggested a crossover u-joint and the 1330 yoke.
Let me know.

Richard

 

So, by going with the cross-over yoke, I will use my existing shaft and enjoy the additional spline engagement provided by the longer 1330 yoke.

You will send me the 1330/1310 cross-over U-Joint as well?

Lets go ahead and do this. How do you want me to return the the yoke? Can you sent a return shipping label?

Thanks

 

PM sent.

Richard

 

Ok guys, here is a follow up after receiving my new 1330 cross over yoke from Keisler. First I would like to note that my 1310 yoke was leaking oil out of the splined capped area where the shaft passes through the cast yoke. There was sealant there but it still leaked so I would have had to return the yoke anyway. As I learned from other posts, this is not the first time Keisler has had this problem leaking 1310 yokes. In hind sight I should have returned both the shaft (incorrect length) and leaky yoke. The 1330 cross over yoke seemed like an easy fix for the shaft length issue as the shaft I received was for the 1330 yoke not the 1310 (which is what was sent). I paid an extra 99.00 for the 1330 yoke. I received the yoke and and cross over U-Joint (1310/1330) pressed in the new U-joint into my shaft without issue, when I went to remove the caps from the yoke I needed to put the yoke in a vise and use a hammer to break the cap bolts because they were on so tight. Then I installed the U-joint into the yoke and noticed it was a very tight fit. I snugged the cap bolts and noticed there was still a gap between the cap and the yoke and I would have to really torque down the bolts to close the gap. When I tried, it practically froze up the joint. Sooo, I just snugged them and brought the shaft to be balanced, They told me it was to tight to balance. They tried other u-joints but concluded that the yoke was the issue. They had to grind the bearing cups to get it loose enough to balance. I am guessing after all the grinding and fit issues, the usable life of that ujoint was cut in half.....anyway...$50 bucks later..

I installed the shaft but found that there was interference with the tunnel, so I had to remove some fiberglass (cut a hole) in the passenger side of the tunnel. (this is why Keisler uses 1310 Yokes)


Observations: A combination of the wrong part being shipped and bad choices on my part to "fix" the problem cost me $150.00 and a hole in my tunnel coupled with a u-joint that is probably going to fail prematurely and when it does, I am going to have to go through it all over again...

Lesson learned: Check all your parts and don't try to take the path of least resistance if something is wrong. Be assertive with the vendor because the first assumption will be your an idiot.

 

Mine is very very tight on the driver side ??? Is the '79 floorpan/tunnel different ?? I think I'll just beat it up a little to make some room....

 

My emergency brake cable is on the driver side, are you close to that? I would think you would hit the cable before the tunnel.

 

I'll take some photos tonight.... I think my shifter position is a little too far towards the front compared to photos that were posted here.... weired.....

 

Check out my pictures. I thought mine was as well. I used some 1/4" thick foam rubber and cut a spacer from it. I glued the spacer onto the bottom of the rubber boot frame. I removed the clip on the side. This gave me some clearance at the front of the shift tower because it is just a hair above the tunnel as well. I have a picture of it together. I checked it with the trim plate and it is centered in the opening quite nicely. Tomorrow I will post some additional pictures. The white material is duct insulation I stuffed in around the tower.

 

I think that's about where mine is located. I'm not too happy with the plate that I made, I cut the hole a little too far to the left.... .... oh well... as long as there are no open gaps between that and the rubber boot I guess it's ok....

 

Yea, I'm kinda wishing I had waited till I installed the trany before I made the plate, but it worked out ok.

 

I might just make another plate.... at least it all works ... did you see my videos in C3gen ?

The transmission is awesome, a 5spd is so much more fun

 

Here are some more pics