Hi,
Just got a wonderful 2005 XJR which needs a new driver side catalytic converter. I've read the threads here about folks that have switched to 200 cell high flow cats. Any recommendations or issues I should look for? I would like to do this as low cost as possible with something bolt in ready. I'm in the US. Any help or advice would be appreciated.

 

How did you determine you are in need of a new cat? Do you have a hard code?

 

It is rattling pretty badly. Also forgot to mention I need to pass emissions every year. My mechanic is pushing me towards OEM cats since he says the aftermarket ones tend to fail after a year or two.