CAT REMOVAL

jeepmaster · #1 (**permalink**) 07-20-2003, 08:00 PM

ok i need to ask a quick question as im planning to do this after school tommarrow. ive got a 96 XJ and i wanna take the cat off and hollow it out. can anyone tell me how this is gonna sound? im told it will increase performance and flow a little but im worried its gonna sound like a Del Sol with a coffee can on it? can anyone provide me with a description of what it'll be like? ive got the 4.0 i-6 high output (arent they all HO?) kk thanks ~ max[addsig]

Tug-n-pull · #2 (**permalink**) 07-20-2003, 08:00 PM

It will be just a bit louder and a bit more bass. I think they sound alot better with out the cat. Let me know what you think after you get it off there. tug[addsig]

bigTlilODD · #3 (**permalink**) 07-20-2003, 08:00 PM

it won't sound bad at all. I took mine out and left it on my workbench and installed a straight pipe. That way I can through it back on before inspection. If you don't like the sound, get a glass pack muffler. That'll help a bit.[addsig]

MudderChuck · #4 (**permalink**) 07-20-2003, 08:00 PM

On the wifes, old XJ I installed a straight pipe. was a little louder, but not really annoying. After I installed an Edelbrock performance muffler, things got a little louder, but a deep tone. Dogs used to get up and stand by the door, five minutes before the wife got home. Had a one of a kind sound. :-D [addsig]

dingus · #5 (**permalink**) 07-20-2003, 08:00 PM

haha i should take mine out too... its all crumbled and rattly and such... [addsig]

jeepmaster · #6 (**permalink**) 07-20-2003, 08:00 PM

kk the cat removal didnt happen. i was all excited and stuff and had some buddies come over only to find we couldnt break a single nut loose. i stripped one of them. so yea now im lookin for a dremel or something to cut them off with. does anyone know how much the little metal yokes that have the bolts on them cost? cause im gonna thrash that gettin the bolts off. thanks[addsig]

west747 · #7 (**permalink**) 07-20-2003, 08:00 PM

cut those u clamps off with an angle grinder....its quick and too the point...doent matter what you do you cant reuse exhaust clamps..lol oh yeah and those clamps are dirt cheap

edited by: west747, Feb 21, 2003 - 07:44 PM[addsig]

jeepmaster · #8 (**permalink**) 07-20-2003, 08:00 PM

i dont have access to an angle grinder, so im gonna try to find a heavy duty dremel bit for metal cutting or attempt a hacksaw (friend suggestions) it seems to me tho that home place at one time offfered free tool use for a day on home improvement projects. some place like the home depot or something. like if you buy some sort of project materials from them they let you use some tools? i dunno, free tools seems to strike some familiar cord in the back of my mind. any other suggestions as to what i could use? thanks[addsig]

Snitty · #9 (**permalink**) 07-20-2003, 08:00 PM

At first, i took off my muffler, left the cat and replaced the muffler with a pipe... LOVED the sound. then when I did my tranny, I removed the cat.... it made almost NO difference.. in sound and it KILLED performance. I put a cherry bomb on for a muffler, leaving the cat hollowed... it quieted it down a bit and gave me what seems to be the perfect flow. but the sound wasn't so bad ass... by the way... this was on a 4.0[addsig]

jeepmaster · #10 (**permalink**) 07-20-2003, 08:00 PM

so i need to have either the cat or the muffler for best performance? im not going for sound i was just worried id get a bad one. unfortunatly i just spent $10 bucks on a ton of dremel bits and still cannot get that cat off. im just gonna cut it off now, and run it off the down pipe for awhile i spose. any suggestions of what i could throw in the hole im gonna have there? i may just have a friend cut me a section of pipe and re bolt it in there. this is quite a bit bigger of a project than i expected. thanks ~[addsig]

Tug-n-pull · #11 (**permalink**) 07-20-2003, 08:00 PM

Just go to a local exaust shop have em cut and flare both ends a piece of tube to fit between your cuts and clamp it in place. Ez fix. Good Luck tug[addsig]

BigBlackJeep · #12 (**permalink**) 07-20-2003, 08:00 PM

I wouldn't run the Jeep too long without anything giving you backpressure. Without backpressure you run the risk of ruining your valves. If you are just runnin down to the exhaust shop I don't think it would be a problem, but runnin around town for the next year would be. If you can cut pipe in a straight spot on both sides you can buy couplers at just about any auto parts store that will connect the pipes together. Saves you having to run to the muffler shop and having to pay for something you can do yourself. [addsig]

RayOvac · #13 (**permalink**) 07-20-2003, 08:00 PM

Hmm lets see...I have ran my jeep with cat + muffler, no cat + muffler, and with nothing but just a 8 inch down pipe. The down pipe sounded like crap (I have a 4 banger). It was loud though...to the point that it was hard to have a conversation in the jeep. That was till I could get my junk welded back on. My cat was all busted inside so I rammed it out but I still wasnt satisfied with the sound...had like a "hollow tin can" sound. So I put a pipe in place of the cat for a while and I liked it but I then heard a good idea. I took the pipe I was using and welded it INSIDE the cat and put the cat back on. Looks legal and has a good sound to it.[addsig]

jeepmaster · #14 (**permalink**) 07-20-2003, 08:00 PM

ok im gonna cut the cat off and clamp in a piece of metal piping like a test pipe, leaving the muffler etc intact and attached. this shouldnt hurt my performance or ruin the valves correct? ive got no $$ right now and im just tryin to nail a couple low price mods.[addsig]

jeepmaster · #15 (**permalink**) 07-20-2003, 08:00 PM

ok new plan. i put in a test pipe instead of the cat. and remove the muffler and put on a flowmaster 40. any cons to this, any opinions, any whos done this or something like it?[addsig]