Driveshaft angles

Ok...I know this has probably been covered, and (disclaimer) I've looked at quite a few other post on angles...but I'm wondering about my angles. I currently have a 305, hopefully soon to be replace by a 350. It is offset to the passenger side about 2.5 inches, and because of this, the transmission/transfer case is shifted as well. My question is - would this angle cause any vibration -because it is not only vertically angled but horizontally angled as well? I'm a newbie at this stuff so I have no idea how flexible u-joints are. I'm trying to track down noise/vibrations (other than my 305 as it breathes its last breaths.)

Here's a picture...

 

Looks less than 20 degrees each way I think it would be ok.

Scott

 

The double angle isn't ideal. However, it looks like you don't have any lift to speak of, and your rear driveshaft is fairly long. I would say it's ok.

Novak discusses engine placement for SBC swaps on their site. http://www.novak-adapt.com/knowledge/early_cj_gm_engine_conversion.htm They say 1-1.25" to the passenger side. How do you know that yours is offset 2.5"?

Tom Woods has a driveshaft angle primer on their site that could help. http://www.4xshaft.com/driveline101.html

 

Your u-joints need some angle so that the needle rollers in the bearing caps roll around and keep themselves lubed. If your drive shaft was in a perfectly straight line the needle rollers would flatten out and wear groves or waves, however you want to put it, into the bearing caps leading to premature failure.

 

Ok. That's good to hear. Appreciate the responses! Timgr - the reason I know about the offset is because the PO hacked up the cover for the transmission and transfer case, and that's about how far it is from the center to where they are located now. It's purrrrrdy....

 

I don’t think the shifter placement is telling you the full story. There’s a pretty good chance your Jeep had a 4 cylinder originally and I don’t know how they’re placed in the frame but it’s assumable the crank center line would be in a different spot than your GM v-8.
I think a better way to measure that would be to measure from the center of the crank pulley to the frame rail on one side then the other. The difference in the two measurements if your offset.

 

Vibrations could be from any where in the drive train. U-joints, bent wheels, dried on mud (down here it is caliche, which is used for making blocks and is as hard or harder than cement), any thing like that.

The four cylinders were offset to the drivers side to give clearance for the front drive shaft on the passenger side. I thought the Dauntless were also for the same reason.
Why would Novak recommend shifting the whole set up to the right, when there isn't enough room for the front drive shaft to begin with?

determining the center line would probably consist of measuring the crank pulley center to each frame rail, but you probably need to get the same measurement from the center of the throw-out bearing to each frame rail also.

 

Oh, that makes sense then. The V-8’s are placed to the passenger side to clear the steering shaft. Otherwise the exhaust manifold would get right in the way.

The last time I swapped engines I did exactly that.
Once the engine was in place with mounts bolted up and the back supported with a jack stand I measured from the pilot bushing at the back of the crank to frame rail on one side then the other and did the same for the front at the center of the balancer. That’s how I checked offset and the make sure the engine was square in the chassis. It was and had exactly 1” offset to the passenger side.

 

This is really helpful - especially since I'm in the process of tracking down a 350 to replace the 305. Thanks for all the input. One of the issues I have is that there is no adapter plate between the bell housing and the t90. Instead, someone drilled and tapped new hole. I think that's part of the reason the transmission is shifted up and to the left. Is this adapter necessary? My assumption is that they did this so that they would not have to replace the input shaft of the t90 with a longer one. This shift also has had an effect on the alignment of the clutch pivot rod. I'm thinking about doing the AA clutch chain mod as well. Looks like people have had a lot of success with that. Perhaps my next step will be to replace the u-joints to see if that helps any. I had the wheels balanced when I had the tires put on, so I think they should be ok...

 

You might want to get an angle finder and check the angle of your transfer case output and your rear axle pinion. Typically, you want the pinion gear about 1 to 2 degrees lower than the transfer case output. When doing a Chevy conversion, most people level off the carburetor flange of the intake manifold and that places the engine at more of an angle than the original 4 cylinder was at because the Chevy carb flange sits at steeper angle in relation to the crankshaf than the 4 cylinder does.

Years ago I did a Chevy V-8 conversion on my 64 Cj-6 using a Novak kit with a adapter/spacer block about 2 1/2" thick. This requires the use of the Jeep 6 cylinder inputshaft. This combination places the Chevy engine further forward and away from the firewall leaving sheetmetal work to a minimum while maintaining the stock transmission position fore and aft wise but requires that the transmission be shifted about 1 1/2"(If I can remember correctly. It's been a few years) toward the passenger's side in order to allow space between the stock Ross steering and the engine block. It is OK to run the driveshaft at compound angles as long as the angles are not severe. Looking at the length of your driveshaft, 1 1/2" offset sideways is not a problem. Stock 72-75 CJ-5s have noticeable sideways offset.

 

That placing the V8 to the passenger side to clear the steering explains why the later ones run the front shaft down the drivers side of the engine.

 

Yeah well, the newer CJ's went to a GM Saginaw steering gear box located just back of the bumper. The Saginaw box has better mechanical advantage and less slop. My brother did a Saginaw steering conversion on his 68 CJ-5 using a manual gear box. It felt like it had power steering compared to the old stock Ross box.

 

I have a SBC in my jeep, when I had my trans tunnel off, I noticed that the trans didnt look centered in the frame. After a closer look, it was an inch or so to the passenger side.