I can't find a good answer for this- does the X100 (2001 specifically) XK8 and XKR share a common catalytic converter design? Can they be interchanged?

 

As far as I can tell the only different is the exhaust mounting type, the NA is sleeve and the supercharged engines use a flange instead with two bolts. The problem is you can't find new 4.2 catalytic converters which may or may not be a problem as the lower mount won't fit but that might not be a problem. I plan on replacing mine with some stainless steel converters from BM in the UK as they sell off the shelf components for the 4.0. So I will likely say if they work or not whenever I do that. My current converters have rust holes in them and can't be fixed. JAGUAR XKR 4.0 08/98-07/02 Catalytic Converter BM91002H + FK91002C I have no idea if these are going to be more or less restrictive than the OEM converters but we will see, at least they won't rust. Once the car gets to classic status in the Uk the converters are coming off and I will use a downpipe instead most likely to let the engine breath a lot more. Only 20 years to go.

 

FWIW, the parts catalogue shows different part #s for the XKR throughout the years. The mid box is also different between 8 and R.