I got a rear from a guy who says its out of a 50 merc. It was in his T back in the 60's and has chrome backing plates and rear cover. I wanna use it in my roadster project but the problem is that the flange on the center section is not in the center of the rear. It is off by about 1 1/2 inches to the right. My question is, was this stock? If so, why, and how did it work? I don't want to run a cocked driveshaft and I don't want to spend the coin to have it shortened on one side. Guess i'll be looking for a rearend.
shouldn't cause any problems, as long as the engine/trans is parallel to the frame. Ujoints are designed to allow a driveshaft to operate with the ends out of line.....
The engine and trans are parallel, but that just doesn't seem right to have the driveshaft at an angle. Wouldn't it cause a vibration?
no, it won't cause a vibration. That's how driveshafts are designed to work...although normally they only have a vertical offset. But the driveshaft doesn't know whether it has a vertical or horizontal offset, or both, and doesn't really care.
I would think that most Fords, except the banjo rears, were designed that way. The driveshaft may be in the middle in relation to the axle ends, but the center "lump" for the ring and pinion is offset. If you decide not to use it, I could use those chome bits on my '49 rear I'm planning to use under my T. They'd look spiffy with the chrome 1/4 elliptics.
I understand what you are saying that it can be offset either way, but the vertical offset is to compensate when the torque forces the pinion angle from pointing downwards to about level. If that was the case horziontally, the torque would force the rear sideways. I guess a well placed pan-hard bar could control that but I still have a weird sense of, this can't be right.
I believe the vertical offset is a result of having the rear axle suspended on springs. Because of the axle movement up and down from the springs, the vertical offset is a constantly changing thing. That is why u joints are needed. I've heard of the torque effect but in relation to setting up pinion angle, some people believe you should set the pinion angle down a degree or two from what your tranny is. Then when torque is applied, the pinion rotates up 2 degrees and becomes the same angle as the tranny. I believe most people just set up the pinion angle the same as the tranny, no compensating angle added for torque. As far as vertical or horizontal offset, the tranny and pinion only knows of one offset. That offset or flat plane is probably somewhere between horizontal and vertical. Image your car turning in the air on a rotiserrie, you are looking at it from the side. When the car is turned so that both driveshaft ends are an equal distance to you, that is the view where you see the actual angles of the driveshaft ujoints. In that view, the pinion shaft, tranny shaft, and drive shaft are on one plane. i.e. all points on those 3 shafts are equal distant to your eye. Since we set up, from the top view looking down, our pinion and tranny parallel (and likely offset), we don't need to find that theoretical plane to set up angles. Practically speaking if we just create matching angles in the vertical plane, by geometry, the angles will also be the same in that theoretical plane.
Mike, is your 51 like this? Offset, I mean. I see what you are saying, the torque effect will affect the pinion angle but the offset is void in either direction. I guess I like to see things parallel and perpendicular but in this case I need to use this rear so I will make it work and never look at it. Make sure you guys don't tell anyone my driveshaft is crooked. Thanks
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