I put my car up on the alignment rack today and here are readings I got. The only thing I fixed was front toe, which is pretty easy. The rest of the stuff I'm not 100% sure on. I'd really like to find a comprehensive list of how many degrees a value will change for a given shim - any idea where I can get that? It's not in my Haynes...

Caster: I think I am going to leave this on the high side. The machine shows the XJS spec at 3.3" - 3.8", and since the suspensions are largely the same, I'm going to opt for the greater steering input and sportier feel. Is adjusting caster as easy as moving the shims at the bottom of the UCA from the front to the back?

Front Camber: Are the camber shims washer-like or are they bars that slide over the bolts? Do I need to take the UCA off entirely to get the shims on, or just loosen them? How much does camber change for a given shim? I think I saw 1/6" gives 1/4" degree, but I'm not 100% sure.

Rear Camber: Not looking forward to this. I remember seeing two sets of shims on the IRS - one set between the inner half shaft flange and the stub axle, and one set between the LCA-to-diff bracket and the diff. Which one of these should I use to adjust rear camber? How many degrees does a given shim change?

Rear Toe: This is probably a bad reading. """I had a left radius arm bushing fail, and I took it off the car before I put it on the alignment rack. That was my mistake.*** I expect that to correct the toe a little. Any other thoughts on adjusting rear toe? Loosen the rubber IRS-to-chassis mounts and twist with a long pipe?

My biggest concern right now is finding out how many shims I need so I can order parts!!!!! Any ideas?

Also, almost everything suspension is new. All poly bushings up front (except subframe bushings), poly steering rack bushings, all new rubber bushings in the rear, KYB shocks, King lowering springs, 4 new ball joints, 2 new outer tie rod ends. Still waiting on the new wheels and tires.

 

Bootom of the UCA? Not sure what you mean. Caster is adjusted by the shims on either side of the upper ball joint. But, yes, you move them to either the foreward position or rear position. You don't add or subject from the toal number of shims.




Just loosen the arms/bolts and slide 'em in. The Jaguar shims do have a unique shape but the shop that does my aligments always had something close enough to work





The *only* camber adjustment for the rear wheels is at the halfshaft flange. The LCA-to-diff bracket shims are used to align the parts during assembly of the rear cage.





Yeah, there is no *intended* toe adjustment at the rear so anything you do will be by force



Cheers
DD

 

Thanks for the info Doug!

Is there a table somewhere that shows how many degrees each shim will change the angle it is adjusting? Any idea where I could get a copy of that? I could definitely save some time/money on the rack with those figures.

 

I think I answered my own question. For reference, courtesy of cobraclub.com:

Rear wheel camber
One 0.5mm (0.020in) shim alters the camber angle by 1/4 degree

Front wheel camber
One 1.6mm (1/16") shim alters camber angle by 1/4 degree

Front Wheel Castor
Transposing one 1.6mm (1/16") shim alters castor angle by 1/4 degree

This is for an XJS. I'm not sure what year, but I think they're substantially the same as the XJ sedans.

 

I used to use regular old Chevy shims when I did alignments on XJ6 (1/16" 1/8" etc.)
The proper way is to do the Camber shims EQUAL and move the Castor shims on the upper ball joint but I have seen people do the Chevy trick and shim the upper control arm by adding/subtracting or moving them to 'rock' the upper arm.

The slotted shims are easier to move around than the Jaguar WASHER type.

bob gauff