offset vs centered pinion

Stewart Way · 11-21-2007, 12:56 AM

Putting a SS car together for my son, and maybe me, to play with. Its a Mopar and they come with the drive line offset to the pass side around .875 inch. I have access to a new 9" ready to go with fourlink, shock and wheelie bar mounts already mounted and 40 spline drilled axles but it is zero offset. My question is, with a 44" drive shaft that gives me around a 1 degree angle in the drive shaft to the side, will that be a problem? I don't see that that is anymore adverse than a 1 degree dowm angle. Plus, as I look at it, a 1 degree down pinion is no different than a 1 degree to the side and down. Still no more angle in the joint. Don't have the motor and mid plates mounted yet so I could take some of the offset out but it crowds the steering and adds more weight to the drivers side, although not much with 1/2" to 1" change.
As I said, I don't think its a big deal but was wondering what others thought and if anyone has ever played with this type of setup.
I realize that pinion angle eats power, Think I remember something like 1% for every 3 degrees.
Thanks

will prater · 11-21-2007, 07:48 PM

I am no chassis man but I am thinking now the drive shaft would be out in two directions instead of one.

Stewart Way · 11-22-2007, 12:41 AM

Will
Don't think so. Think of the trans tailshaft as the center of a circle and the pinion being the circle. If the circle is a 2" circle the pinion is 1" out. It can be out that 1" anywhere on the c1rcle but the joints only have to make the slightly over 1 degree correction every revolution. Doesn't matter where on the circle the pinion is. We are just used to thinking of the pinion directly below, in line or above thr centerline. I think.

will prater · 11-23-2007, 03:09 AM

Yep I see what you are saying and it sounds right to me. After thinking about it I doubt if very many are exactly centered anyway. Most seem to have a little side to side movement.

Jeremy · 11-24-2007, 11:21 AM

Years ago a friend built a C/G Angela and used a Jeep rear end which had a large off set to one side, I forget which way. We really didn't like doing it but did it anyway and never had a problem with it. I'll bet it's still sitting in his garage.
Thanks

Bryan Broaddus · 11-27-2007, 03:48 AM

My Super Stock car has had an offset pinion in it for 13 years and it has never caused any trouble.

If I were building a new car, I would center the pinion but if it is set up that way now I would not worry about it.

11-21-2007, 12:56 AM	#1
Stewart Way Member Join Date: Aug 2003 Location: Atlanta Posts: 476 Likes: 20 Liked 70 Times in 22 Posts	offset vs centered pinion Putting a SS car together for my son, and maybe me, to play with. Its a Mopar and they come with the drive line offset to the pass side around .875 inch. I have access to a new 9" ready to go with fourlink, shock and wheelie bar mounts already mounted and 40 spline drilled axles but it is zero offset. My question is, with a 44" drive shaft that gives me around a 1 degree angle in the drive shaft to the side, will that be a problem? I don't see that that is anymore adverse than a 1 degree dowm angle. Plus, as I look at it, a 1 degree down pinion is no different than a 1 degree to the side and down. Still no more angle in the joint. Don't have the motor and mid plates mounted yet so I could take some of the offset out but it crowds the steering and adds more weight to the drivers side, although not much with 1/2" to 1" change. As I said, I don't think its a big deal but was wondering what others thought and if anyone has ever played with this type of setup. I realize that pinion angle eats power, Think I remember something like 1% for every 3 degrees. Thanks

11-21-2007, 07:48 PM	#2
will prater Member Join Date: Sep 2002 Location: Carthage, MO Posts: 108 Likes: 2 Liked 7 Times in 4 Posts	Re: offset vs centered pinion I am no chassis man but I am thinking now the drive shaft would be out in two directions instead of one.

11-22-2007, 12:41 AM	#3
Stewart Way Member Join Date: Aug 2003 Location: Atlanta Posts: 476 Likes: 20 Liked 70 Times in 22 Posts	Re: offset vs centered pinion Will Don't think so. Think of the trans tailshaft as the center of a circle and the pinion being the circle. If the circle is a 2" circle the pinion is 1" out. It can be out that 1" anywhere on the c1rcle but the joints only have to make the slightly over 1 degree correction every revolution. Doesn't matter where on the circle the pinion is. We are just used to thinking of the pinion directly below, in line or above thr centerline. I think.

11-23-2007, 03:09 AM	#4
will prater Member Join Date: Sep 2002 Location: Carthage, MO Posts: 108 Likes: 2 Liked 7 Times in 4 Posts	Re: offset vs centered pinion Yep I see what you are saying and it sounds right to me. After thinking about it I doubt if very many are exactly centered anyway. Most seem to have a little side to side movement.

11-24-2007, 11:21 AM	#5
Jeremy Junior Member Join Date: Dec 2002 Posts: 95 Likes: 0 Liked 1 Time in 1 Post	Re: offset vs centered pinion Years ago a friend built a C/G Angela and used a Jeep rear end which had a large off set to one side, I forget which way. We really didn't like doing it but did it anyway and never had a problem with it. I'll bet it's still sitting in his garage. Thanks

11-27-2007, 03:48 AM	#6
Bryan Broaddus Member Join Date: Jun 2002 Posts: 104 Likes: 2 Liked 18 Times in 4 Posts	Re: offset vs centered pinion My Super Stock car has had an offset pinion in it for 13 years and it has never caused any trouble. If I were building a new car, I would center the pinion but if it is set up that way now I would not worry about it. __________________ Bryan Broaddus 7568 STK ,SS