So, I recently found out that my little island paradise here has no regulations regarding the presence of catalytic converters in cars. Apparently they can be removed and no one will bat an eye when it comes time to inspect the car.

So I was wondering, is it possible? Are there any benefits? Do they outweigh the environmental impact?

The guy who told me this, said that as long as the car doesn't have O2 sensors after the cats, that it should be possible.

I plan on eventually upgrading my exhaust, so I might take this in consideration.

 

The XKs do indeed have O2 Sensors both Before and After the Cats to check their efficiency.

 

I have single cell cats on my XJ

 

Hmm, Paul, I guess that makes sense. So, if that's the case, keeping some sort of cats is a must on these cars.

Tony, those single cell cats, how do those work?

 

The cats went on my XJ so to save a few $$ I took the cat bypass pipes of my race car, I have no code issues, the engine sounds fine and runs well

 

I wouldn't remove them. There seems to be no benefit to doing so.

I follow the Corvette forums religiously and those fanatics are addicted to HP and there doesn't seem to be more than MAYBE a 5 hp gain as confirmed by numerous dyno charts. Sometimes not even 5 HP.

Modern catalytic converters are well designed and I wouldn't mess w them.

JMHO

 

From the descriptions I have read regarding our stock converters - we might do better than 5 hp. Anyone with any dyno results?

 

One of the biggest restrictions is the cats, however these engines do like a certain amount of back pressure and by free flowing the engine too much you loose power in the lower rev range but gain it in the higher....

Yes you will show more than 5hp but you will be doing 3000 revs to show it and over 100 mph so you will not gain any advantage, on my track car I have a manual box and can hold the revs as high as I like so can take advantage, keeping the lower cell cats would be better than none at all in a road car

 

Tony does this mean high flow cats aren't a good option on these cars?

 

No I would not say that, but I would say try not to go over board, if you had 200 cell cats with hardly any exhaust boxes you would have quite a free flow system, you would gain more power towards the top end but lose it at the bottom, and lets face it low down power is much more applicable for every day use

 

Have a customer and member here who put on nameless cats and dynod before and after same day they changed cats and showed 25 hp to the ground. Which was a good improvement on his 07 xkr

 

25 hp sounds good, but is it noticeable?

 

No cats, no mufflers after the axle. I still have the factory resonator

https://plus.google.com/u/0/photos/y...58934572899632

 

If you scroll down on the website below you will see o2 cheaters that extend the sensor & work on our cars. I have used them for 2 years with no issues.

http://www.newchallengerstore.com/Ch...ce_Exhaust.htm

 

Michael, the link is asking me to create a G+ profile. Could you upload the file to the forum?

 

Try this one

https://www.youtube.com/watch?v=Z4Ik...ature=youtu.be

 

Holy crap, that's a lot of smoke!

 

That's not smoke. It's just what hot exhaust (water vapor) looks like in very cold weather.

 

ha! I have noticed that there is a lot more water vapor without cats on those chilly mornings.

 

Right; water vapor...