catalytic converter question

Hey all. I need a new cat and just have a few quick questions. I'm looking for a higher flow then stock, so a carsound one came to mind, but its universal. It would save a lot of time going with a catco (direct fitment) but are they just as high flow as the carsound ones?

I know the stock cat has a square flange that connects it to the s-pipe, would local auto shops carry something like that or maybe the dealer that I can weld on myself? Or would it just be easier to just have a shop weld the cat right to the s-pipe?

Bah sorry for all the newb questions lmao, did a search but nothing really answered anything. Thanks :sunshine:

I got a carsound one. Wasn't universal- direct fit just like the old one. Got it off www.truckperformance.com when they had a big sale for 90$

I had a pipe stub welded to the flange (after I cut it off the cat) and used a BBChevvy converter and a Walker Turbo muffler (prices were right - $20 for the muffler and the cat came out of my then-boss' shop for nothing.)

By all means - KEEP THAT FLANGE! You'll be kicking yourself if you have the whole mess welded together the first time you have to pull the transmission...

5-90

You failed to mention what year your XJ is. If it's 96+, it's OBDII and will be more expensive because it needs the provision for the second O2 sensor.

I got a Carsound cat and a muffler shop drilled and welded an O2 bung in for me.

again if you have the obd II system, the one i mentioned comes with the O2 sensor mount and its oem size, shape, everything= trouble free

crap I'm sorry I forgot to mention its a 99'. The carsound one I was looking at was http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=7924349283&category=33629 Would that be the correct one? Is there any place any one knows of that I could get a new piece with the right flange I coudl weld on?

And dothedew what model from there are you talking about, or maybe a link? Thanks a lot all.

I picked up a rustys off road high flow cat... fitment SUCKED but its decent.

uhhh. hmm im missing somthin here...flange? I'm guessin somthing with the exhaust changed in the 99 year. anyway, heres a link to the one I got a few months back http://truckperformance.com/products/?searchtype=67d&sortorder=DAAAA&productcategory=Catalytic+Converters&category=Engine+%26+Performance&sf1=JEEP&sf2=1997&sf3=Cherokee&sf4=Vehicle+Specific+Applications&sf5=4.0l- not sure if it'll help now that ive heard yours is different, i checked on here and theres not one listed for 99+

NeoMax said:

crap I'm sorry I forgot to mention its a 99'. The carsound one I was looking at was http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=7924349283&category=33629 Would that be the correct one? Is there any place any one knows of that I could get a new piece with the right flange I coudl weld on?

And dothedew what model from there are you talking about, or maybe a link? Thanks a lot all.

Click to expand...

That's the one I got, the #94035, in fact I have two of them sitting right here in my office just waiting for the ones under my XJ's to wear out or get bashed up, since they were so cheap. I got them some time ago on EBay, for under $40 each from that same company. I think it came to about $90 for two of them shipped at the time. Anyways, that was a great company to deal with, excellent communication via email, and shipping was excellent.

I am looking at replacing a muffler shop universal (cheap, small, non OEM cat I had installed 2 years ago when I first bought my XJ) Cat converter on my mostly stock 87 XJ, 4.0, Renix beasty.

BUT, Everywhere I have looked so far, including the tech threads here, and some online parts houses, they do not have any solid performance data that I can find of any kind, anywhere.

All I see is cute ads for little black boxes (OK, Silver metalic boxes) that all claim to be the greatest thing since sliced bread. I am looking for test data on back pressure loses across these Cats at various flow rates since pressure loss, or reduced pressure loss is what I want.

Anybody have any data, seen any data, run any tests, or have a clue as to what would be a good solid cost effective Cat choice based on up front costs and minimal back pressure for an OEM Renix 4.0?

Thanks!