Tweety walks like a penguin
Posted: Sun Feb 26, 2012 9:11 pm
Yep, too much toe in and far too much negative camber.
This has been a running issue for some time. Forget about warranty, thats gone, and over the past few weeks have been on a steep learning curve about the IRS design.
Panther make their own IRS. The monocoque chassis incorporates an alloy box shaped fuel tank at the rear is welded the swing arm mounts that are---NOT adjustable, eg no cammed bushes etc. The swing arms are made from alloy box shaped and welded together. A lot of work but this is how it had to be to creep under the maximum weightlimit at the time of 450 kgms wet. This limit has since been eliminated completely.
A while ago you might recall I upgraded to better quality airbags. They were not as long as the originals. So a spacer was sort and I had twox 30mm spacers made out of hard plastic. This brought the ride height back up to original and prevented the shockers from bottoming.
In a nut shell there is 3.8 degrees negative camber on the LHS and 2 degrees on the RHS. Specs for a type 3 VW are 2 degrees positive camber both wheels. Thats why when new the type 3 and the beetle (IRS) for that matter had their rear wheels like this \ /. But Tweety sits like this / \ all the time and scrubs out tyres inside.
Some suggestion on aussieveedubbers has been to use a press to twist the swing arm. But this is not VW rear end. It is unique with that alloy boxed shaped swing arm. Dont even want to go there!!. To me there are only two alternatives. Modify the swing arm mounts to make them adjsutable. (Dont feel like doing that) or insert shims on the spindle
Now for the maths.
A spirit level and other measurements found that from the bottom of the LHS tyre to the top (600mm there is 35mm from vertical and 40mm from where the positive camber should be.
Assuming the shim is 100mmx100mm (dont want to go to the trouble to take off the disk and measure yet). The shim at the bottom can be 3.5mm thick and the top 10.1mm thick and narrowing at the front by 1.5mm.
and the RHS about half that.
sheesh....so easy eh. I'll need to get my engineer to take off the disks, make and then fit the shims etc.
Have google shims but not confident they will do the job, assuming the shim pattern is the same for my bolt pattern.
The 30mm spacers
Note the swing arm
its clear here with the old tyres. And thats unloaded.
Any input appreciated.
This has been a running issue for some time. Forget about warranty, thats gone, and over the past few weeks have been on a steep learning curve about the IRS design.
Panther make their own IRS. The monocoque chassis incorporates an alloy box shaped fuel tank at the rear is welded the swing arm mounts that are---NOT adjustable, eg no cammed bushes etc. The swing arms are made from alloy box shaped and welded together. A lot of work but this is how it had to be to creep under the maximum weightlimit at the time of 450 kgms wet. This limit has since been eliminated completely.
A while ago you might recall I upgraded to better quality airbags. They were not as long as the originals. So a spacer was sort and I had twox 30mm spacers made out of hard plastic. This brought the ride height back up to original and prevented the shockers from bottoming.
In a nut shell there is 3.8 degrees negative camber on the LHS and 2 degrees on the RHS. Specs for a type 3 VW are 2 degrees positive camber both wheels. Thats why when new the type 3 and the beetle (IRS) for that matter had their rear wheels like this \ /. But Tweety sits like this / \ all the time and scrubs out tyres inside.
Some suggestion on aussieveedubbers has been to use a press to twist the swing arm. But this is not VW rear end. It is unique with that alloy boxed shaped swing arm. Dont even want to go there!!. To me there are only two alternatives. Modify the swing arm mounts to make them adjsutable. (Dont feel like doing that) or insert shims on the spindle
Now for the maths.
A spirit level and other measurements found that from the bottom of the LHS tyre to the top (600mm there is 35mm from vertical and 40mm from where the positive camber should be.
Assuming the shim is 100mmx100mm (dont want to go to the trouble to take off the disk and measure yet). The shim at the bottom can be 3.5mm thick and the top 10.1mm thick and narrowing at the front by 1.5mm.
and the RHS about half that.
sheesh....so easy eh. I'll need to get my engineer to take off the disks, make and then fit the shims etc.
Have google shims but not confident they will do the job, assuming the shim pattern is the same for my bolt pattern.
The 30mm spacers
Note the swing arm
its clear here with the old tyres. And thats unloaded.
Any input appreciated.