One of mine has gone bad. Anyone junked both cats and replaced with straight pipes, what else needs doing to fool New York emissions testers.Although I do "have a guy " if emissions becomes a problem.

Any effect good or bad on performance and how much louder will that be.

 

I did on my '07 XKR as one of the cats failed a few days before Xmas so my mechanic thought it best to just take them both off.

I certainly wouldn't recommend it. The car was stupidly loud, very raspy and my wife said I stank of exhaust fumes after parking the car in the garage, I went with high flow cats in the end plus a custom middle resonator.

 

Unless you’re building a race car or don’t mind noise and smelly exhaust I’d not recommend it either. And high flow aftermarket metal spun cats won’t last long and will be noisy and smelly too. There are some aftermarket ceramic versions which aren’t too expensive.

 

Suck it up and get the right cats. You'll regret if you don't.

 

Some improvement on performance. You will also need an ECU tune to get rid of the check engine light and tweek the ECU to actually use the potential horsepower. Pm me if you need help with this.
no cats on mine

 

The factory cats bit the dust at around 70,000 kms.
And revving the engine at the Canadian F1 weekend in Montreal isn’t kind to them.
I’m around 160,000 now and when I punch it I throw the dreaded O2 code (which does clear itself after a few days). Time for replacement cats… again.

Just like bulbs, filters (on our cars), etc, I will be replacing the pair of them. Like before, and as the car is tuned for it, I will be replacing the 200 cell cats… with 200 cell cats.

I wouldn’t run without cats. Its not kind to mother nature.

 

In the US, cats are guaranteed for 80,000 miles or eight years, whichever is first. That's a DOT requirement.

 

roughly the same here, I think. But when Jag quoted the replacements after the 6 years warranty I looked out for the options.

 

If you need that Tuned for 200 cels , let me know

 

Don't want your fancy Jag smelling like rotten eggs with no cat's.