rear camber and brake discs s2.2

[gvy]

3 years ago , my engine and gearbox was out for a gearbox repair and revision.

Ever since I remounted everything, it worried me that on both sides the rear brake discs came so close to the caliper mount at the inner side.

With a passenger in the car and when cornering slowly to the right, I could hear a knocking sound, that worried me. Something was touching.

 

 

So I decided to have a look at it.

I unbolted the driveshaft flange

I removed the brake calipers and unbolted the calipermounts.

I unbolted the brakediscs and driveshaft adaptor and removed them.

 

Between the differential flange and the driveshaftadapter sits a 1.5mm spacer.

I copied that spacer and made an extra one out of a 1.5mm plate, so the total thichness now becomes 3mm.

 

 

And I put it in place above the existing one:

 

 

Then I remounted everything .

The result looks much better : The brakediscs sits centered:

 

 

And on top, my rear camber , that was to negative is now OK .

On an S1 and S2 (S2.2) the driveshaft is also the upper suspension arm. So by altering its length the camber changes. I was surprised and happy that the 1.5mm extra spacer has altered the camber about 0.5°

 

Greets

 

Geert

 

 

[giorgio67]

Don't know if adding 1.5mm will be good for bearings...

Regarding camber I think needs to be negative?

 

Giorgio

[gvy]

Giorgio,

Camber should be 0°30' negative +/- 0°15'. Mine was more negative.

Regarding the bearings. In my opinion There is no additional load on the differential bearings.

Look at the picture below.

Anyway. The brakedisc should be centered as in my second picture and except for disassembling the output shaft housing and playing with the distant spacer inside (which does the same as my spacer by prolonging with 1.5mm), there was no way of achieving this.

 

 

[jonwat]

The original Lotus Europa also had the same design (taken from Chapman's racing cars) where the drive shaft also acts as the top suspension member and they were notorious for wear resulting in way too much negative camber. In fact when following one around the bends you could see the wheels go from negative to positive & back again as the car cornered. 

 

The solution, as Geert has done, was to add shims to the gearbox output shaft. 

 

Jaguar also, until the very latest models, used the same rear suspension design & camber change is also achieved by the same method.