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Can anyone suggest a quality Hi-Flow Cat for me?


NAXJA Forum User
Rumson, NJ
I have a Gibson Catback Exhaust on my 00 XJ and was wondering a good Hi-Flow Cat that would help some HP gains. Thanks fellas!
truckperformance.com has them for something like 189.00. Carsound makes them. I have one on my 88, but one problem. There isn't one cat back that is emissions legel for OBDII Jeeps. So you can install it but it might not pass emissions, the truckperformance.com site tells you all about it. Check it out.
I got a Random Technology cat for my '96. Hi-flo, well made, fitting for O2 sensor. Picked it up from Quadratec.
I have the carsound HF Cat that Juice is talking about, just got it on two days ago. I am currently monitoring hp and mpg ranges. I got from the header all the way back replaced, 2.5", the HF cat we are talking about and a tiny tiny Glasspack (thrush) I think. The thing screams like a raped ape compared to my old stocker exhaust that was 10 yrs old. I'm diggin' it.
got a catco hi flow model out of summit for 70 dollars shipped. Flows really well and is small enough to tuck up under the body.
Another vote for the Catco from Summit Racing.


I see you have a 2000, and you're from New Jersey. Are you aware that it is against Federal law, and probably against New Jersey law, to remove or alter an OEM cat unless and until it has failed? The 2000 OEM cat really is pretty much a high flow unit, unlike the really old OEM units. IMHO you're just looking to waste your moeny and risk getting a citation, for what will most likely be a very negligible gain in performance.
Lucas said:
got a catco hi flow model out of summit for 70 dollars shipped. Flows really well and is small enough to tuck up under the body.

How is the sound and power?
Hi-flow cat?

I saw some stock #s for emission catalysts recently, the 4.0L and the 5.2L used the same part #. If it will flow the V-8, it is probably good enough for the in-line 6 ;) . I also asked some of the guys at Jeep division and they told me the same thing..."the stock cat is fine". I've heard similar things about the exhaust manifold, flows nice....no need to change it unless you are REALLY bumping up the HP! :eek:
how about Rustys hi flow cat?

i was thinking about getting a whole cat back from him, and my cat recently went bad, so im gonna replace that as well, and figured it might be easiest to get it all from there.
which is better-delta flo or flowmaster?
Ive got a Magna Flow satinless...it is pretty good....nothin to special
exhaust choices

I had the same question about mufflers. Rusty's is a good (cheap) place to buy an exhaust. Some guys said they had Flowmasters and found too much resonance. I have one on my GMC w/350 and it sounds TITS! No resonance (no cat either ;) ) I also had a Flowmaster 50 series on a 99 Dodge 4X4 w/360 and V-10 cat....got quite a bit of resonance on the freeway.
i recently read an article http://www.go.jeep-xj.info/HowtoExhuast.htm about how exhaust velocity affects resonance. That being the case I might just go with the Flow's because they don't use fiberglass packing (burns out) in their mufflers.