I have read all of Bernie Embden's wonderfully written guides on the maximum tire size that can fit on an XJS, and was resigned to getting 17x8 rims for my car.

And then I saw this:


How did he get 12" in the back and 10" in the front of that Jag? (Try to ignore the JC Whitney-ed out interior)

Is it as simple as he makes it sound in the comments:

I had to install adapters from a jag bolt pattern to a GM corvette bolt pattern , plus the adapters needed to be 2" wide in front & 2.5" in back so that you would have the width & the fender clearance , going to 18" x10" wheels gave it a wider stance 6" and lowered the Jag by 2" gave it a 8" wider 4" per side in the back . Gave the Jag an aggressive look to it over stock wheels .

 

"Tuned port" GM V-8 with genuine V-12 emblems still on the car. SMH!

 

I have 16x8 BBS with 245/50-16 all round and do not rub even on max bump. Offset is the key. My rear offset is 33 and front is 20.

Where tyres rub on the XJS is on the inner part of the outer fender above the wheel arch. 12" wide on the rear may fit depending on the tyre size, ride height and offset. I have seen 10" with 255/50-16 on an XJS that do not rub.

 

The original BBS foreseen for XJS at that time were the following models:
- BBS RS 020 16 5х120.65 7.5J ЕТ30 for the front; and
- BBS RS 028 16 5x120.65 8.5J ET30 for the rear.
These had the 73.9 mm hub diameter and the 120.65 PCD that were specific for mounting on XJS.
Only some BBS rims for BMW or Vettes had specs close to that but going to these BBS models meant going to a PCD of 120.0 and possibly a different hub diameter, so needs of adapters and risks of fitting and running.
So what did you fit?

 

My BBS were for an XJ40 fitment 33 offset and PCD 120.65. Here in Australia spacers are illegal unless they were OEM fitted.

The wheel shop machined the fronts and fitted a spacer which is screwed into the rear of the wheel, thus becoming part of the wheel and not a bolt on spacer.

I do have 3 different sets of wheel nuts, Fronts are long mag nuts (similar to the stock Starfish but longer) the rears use acorn nuts, and I have the original nuts in the boot for the spare.



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