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Wyn
16-06-2012, 10:55 PM
To overcome a prob I have with me propshaft tail flange hitting the rollbar on overrun
Larger GTST diff flange fitted (below) along with large prop uj and new mount arleady fittted ..

( see me extra techy pic ;) )

http://img.photobucket.com/albums/0703/900ss/260z/th_6595f779.jpg (http://img.photobucket.com/albums/0703/900ss/260z/6595f779.jpg)
http://img.photobucket.com/albums/0703/900ss/260z/th_6b7811b0.jpg (http://img.photobucket.com/albums/0703/900ss/260z/6b7811b0.jpg)

What odds will it make if I raise the nose of the diff?
ie put a thicker spacer under the frt mount to lift the diff
I've already fitted a 5mm spacer but it still needs more?
Or do I lower the rollbar? Space it down somehow
What odds would that make to the handling ?

tel240z
16-06-2012, 11:08 PM
Not a lot to the handling but if it was me i would position the diff in a near perfect straight drive line for the prop and lower the anti-roll bar out of the way, iff possible that is

jonbills
16-06-2012, 11:14 PM
Lowering the ARB would be the thing to do I think. It'll just put it under more tension. So less roll.

zbloke
16-06-2012, 11:14 PM
if it was me i would position the diff in a near perfect straight drive line for the prop and lower the anti-roll bar out of the way, iff possible that is

Agreed, failing that remove the rear ARB completely and see if you like the way the car handles without it?

And if you feel you really need a rear ARB and can't lower it so your happy with it how about a rearward mounted ARB, goes round the back of the diff?

Wyn
16-06-2012, 11:21 PM
lower the anti-roll bar out of the way

Rollbar seems the answer then ..
Only way I can see around that is ...
Cut the "U" brkts from the shell and space them 20mm down or so?
or
Have some sort of "U" clamp made that allows the rollbar to drop down when fitted?
Or is there another way ?

Wyn
16-06-2012, 11:25 PM
Agreed, failing that remove the rear ARB completely and see if you like the way the car handles without it?

And if you feel you really need a rear ARB and can't lower it so your happy with it how about a rearward mounted ARB, goes round the back of the diff?

Didn't think of that, cheers :thumbs:

bigblock
17-06-2012, 11:21 AM
Be wary of extreme prop shaft phasing angles if tilting diff/engine.PS seems appropriate place to add attachments for anyone not aware of the importance of driveline alignment(be aware attachs are probably for non solid/rubber mounted diffs as i just lifted them on an ad hoc basis from one of my folders, but give the general idea of alignment).

Rob Gaskin
17-06-2012, 11:58 AM
Could the ARB be altered in shape slightly by heat treatment from a professional spring manufacturer?

moggy240
17-06-2012, 02:13 PM
diffmount (http://arizonazcar.com/diffmount.html)

if you scroll down there is a picture of a rear mount roll bar

SKiddell
17-06-2012, 05:59 PM
Engineering 101

A zero angle on a universal joint is bad engineering practice they need at least 1 degree of angle to keep the needle bearings moving and wearing evenly, zero angle over a prolonged period = needle bearings fail, joint fails.

Set it to a minimum of 1 degree, that way the bearings will be constantly moving.

johnymd
17-06-2012, 08:29 PM
Lowering the arb will have no effect of altering the stiffness as it only works on a differential principle between each side.

If you are going to move the front mounting points you could also look at moving them forward in the car as the arb ends come pretty close to driveshafts outer gaiter.

There is a school of thought that says remove rear arb and use stiffer springs.

Mine runs very close but just misses. I've gone back to the standard z diff mount but used the the wrap over cradle and cuttdown bump stop that came with the kit I bought.