calling TT (and others): diff question

[clutchdust]

let's say i wanted to move my differential back about 3" but keep the same basic location of my spindle bearings (actually they will be moved outboard about 3" also). so the rear will still be parallel to the axles in the horizontal plane but offset about 3" in the vertical. not sure what degree that would put my u-joints at, but would that create a reliability issue?
so, to clarify, there would be a total of 6" more width between the two outer u-joints <at the trailing arms> but the diff will be set 3" further back from it's current location. (and i already know the rest of the rear suspension will change. that's kind of the idea)

 

[Twin_Turbo]

Not a big problem but keep the angles to a minimum (< 4 deg or so would be my guesstimate for a max), the C5 and 6 actually have the spindles in front of the ring gear center but they use a cv. If you're going outboard, 3" might be doable. Better calculate how much the angle will be first. Since the angles will be equal and opposite in the plane you're moving the diff's location in, it's not a big problem.

 

[kwplot34]

What does moving the diff back do for the car,i can see moving it up or down but back

 

[BBShark]

Not a big problem but keep the angles to a minimum < 4 deg or so would be my guesstimate for a max


3 inches back would be about 10 degrees. Just a guess but I think you may have axle phasing problems with that because u-joints are not constant velocity.

 

[clutchdust]

what's the max angle on CV joints? i could go that way.

34, there is no noticeable advantage to moving it back, but that's not the objective. more of a side effect.

 

[kwplot34]

what's the max angle on CV joints? i could go that way.

34, there is no noticeable advantage to moving it back, but that's not the objective. more of a side effect.

OK i'm still lost but there is nothing unusual about that,somebody will eventually tell me where to go :goodnight:

 

[69427]

what's the max angle on CV joints? i could go that way.

34, there is no noticeable advantage to moving it back, but that's not the objective. more of a side effect.

Okay, you've got my engineering curiosity aroused. If you don't mind, can you let us know what you've got planned here? There's quite a few hotrodders on this forum who enjoy seeing something out of the ordinary.

 

[clutchdust]

o.k. fine, my intention is to make a drop in cradle, ala c5/c6 that contains the entire differential, double A-ARM configuration. to do so though, i intend to tie the cradle in at the point where the differential currently mounts on the front as well as where the trailing arms and the rear crossmember. i will probably go with an earlier dana 36 or a c4 dana 44 so i can use the factory holes to secure the diff to the new cradle. now, when i say 3", i'm thinking that will be the max it will have to relocate. i want to keep it at a minimum. we'll just have to see.
then of course, the ultra cool part will be the cantilever coil over set up.
:evil:<muhahahahaha>

 

[Twin_Turbo]

the 80-82 diff is a 44, not a 36.

why move the diff back? just cut out the battery boxes, that's what I did.

Cantilever coil over setup?

 

[clutchdust]

aware the '80-82 is a 44. it also has the tongue built in, whereas the earlier iron 36s and later c4 danas don't. i'm not really interested in moving it back, i just think from looking at it that the space available will dictate.
as for the cantilever coil over set up, also more a function of space and stuff. i really don't want to cut the body. that's why i want the entire thing to be a bolt in cradle.

 

[010752]

let's say i wanted to move my differential back about 3" but keep the same basic location of my spindle bearings (actually they will be moved outboard about 3" also). so the rear will still be parallel to the axles in the horizontal plane but offset about 3" in the vertical. not sure what degree that would put my u-joints at, but would that create a reliability issue?
so, to clarify, there would be a total of 6" more width between the two outer u-joints <at the trailing arms> but the diff will be set 3" further back from it's current location. (and i already know the rest of the rear suspension will change. that's kind of the idea)

The oem setup on a Pantera are almost exactly as you propose, except the differential is approx 3" forward of the axles rather than to the rear.
Keep in mind the Pantera uses much larger ujoints and slip axles too.

Great idea.

 

[BBShark]

what's the max angle on CV joints? i could go that way.

Are you thinking of using CV joint axles?

 

[clutchdust]

The oem setup on a Pantera are almost exactly as you propose, except the differential is approx 3" forward of the axles rather than to the rear.
Keep in mind the Pantera uses much larger ujoints and slip axles too.

Great idea.

good to know. i hope to minimize the amount the diff is off center but i think 3" would be about the max acceptable limit. thanks.

Are you thinking of using CV joint axles?

if the angle is too great for a conventional u-joint set-up, yes.

 

[BBShark]

Are you thinking of using CV joint axles?

if the angle is too great for a conventional u-joint set-up, yes.

I am looking for a source to shorten CV axles. Do you know anyone who does this?

 

[TimAT]

I'd think that any good driveshat shop would be able to custom make CV axles. Or even a good welding shop. Cut the end and shorten the axle then weld it back up and heat treat it.
Are the axles themselves just a solid bar with the CV on one end and a spline on the other?

 

[BBShark]

Solid with a CV joint on both ends. I haven't found anyone who does it yet.

 

[phantomjock]

Reviving an Old Thread...

Does anybody know if VegasJen in previous life as clutchdust ever tackled this project?

Seems like an interesting effort.

Cheers - Jim