Another exhaust thread

[shakes]

But hopefully little different.

Has anyone played with different cat convertors or mufflers to get the best power/economy out of their XJ.

I've also never played with cat convertors, every single one seem's to claim 'hi flow' which brands actually flow better while converting the gases and keeping the o2 sensor happy? Does the XJ or OBD2 like a particular one in general.

Same silly questions for the muffler. Is there a particular one the forum favours ? and why?

This is the first car I've had where drone etc will be an issue. I've seen JJ mention 2.5" through. then 2.25 from the muffler to the dump? It will be mated to Hitech Headers if that makes any difference.

I've also seen some members buy complete systems online from somewhere. (do you think I can find them now )

[junglejuice]

Iron Rock Offroad sells pre-fabbed exhaust systems for the Xj, have a read of Gojeep's site for more info on the 2.5"/2.25" systems....

[darksidecustoms]

I'm in the same boat - need to swap leaky exhaust before pink slip in July.
I've been looking lately and having trouble finding a bolt on front pipe (headers to cat). I already have stainless headers that bolt to stock front pipe - I think they're a Banks knock off.
It seems many in the US use the Walker front pipe - even though it's crimped bends, it doesn't have the big restrictive dimple designed to heat up the cat from the factory.

[Windex]

I can vouch for the Iron Rock setup. I have been running it for awhile now and it rocks. I have yet to get some extractors fitted up(saving some coin for it). Not sure how much difference it made economy/power wise but it does sound alot better.

[XJClassic]

I had a leaky muffler so went for a less restrictive custom-made set-up from before the cat back.

Long story short, it was a waste of time. It took three goes by the exhaust bloke before I was happy with it. The drone was giving me a headache. I can still hear my wife coming home in the thing from the back of the house... so it is louder than stock but not objectionable.

It now has a Nissan GTR cat (yes, really!) and I think a Redback muffler. 2 1/2 to 2 1/4.

Perhaps the set-up mentioned by others above is the way to go - it is consistant where as if you go for a custom job like mine, you're relying on the bloke to know what he is doing. Not all do.

[black-xj]

I have done my exhaust myself... Check 'black-xj's resto' for some pics and muffler part number...very happy with this set up.

[anthonygubbin]

I have gotten rid of the centre in my CAT and it has not affected anything. Might have increased the power slightly. No noticeable additional noise. I doubt I will ever fit a new one unless I have to, to fit the new larger exhaust which is on the wish list.

Regards A