To Remove Cats Or Not Remove Them...

[New97owner]

I have heard conflicting reports on converter removal on a '97. I would like to remove them, and also remove the resonators, replace with a straight pipe, and leave the rear muffler as it is. But some tell me that I might get a code thrown on a '97, due to the rear O2 sensors. If this is so, would I be better off with O2 sims, or purchasing high-flow cats, then removing the resonators. Also, could anyone tell me how it will sound with no cats/resonators, versus high-flow cats/no resonators, running the rear muffler only. Also curious to know how it would sound with high-flow cats, no resonators, and straight pipes instead of a rear muffler? Thanks all...I would love to get rid of the cats all together, but don't want to throw a code...
Mike

 

[LETHAL GTS]

Your '97 doesn't have the rear O2 sensors, so you don't have to worry about throwing any codes.

Please do your exhaust upgrade and let us know what you think. I have a buddy who is thinking of doing the same thing, but is too chicken to try. I would like to give him some feedback.
BTW you will notice an increase in power by removing the cats and resonators.
Thanks
TJ

 

[TomH]

You won't throw a code, I have a 97' too, no cats or muffler, just the resonators. It is a little noisy for extended highway driving but just fine around town. I'd say just do it.

 

[Anaconda]

It's worth doing just to keep the interior cabin temperatures down. That's the main reason that I removed mine. But, as an added side benefit, you will drop like 40 or 50 pounds, get some horsepower, and sound better.

 

[VPRVENM97]

Remove the cats, keep the resonators, delete the rear mufflers and have a muffler shop install an X-pipe crossover. If you think it's too loud for extended driving (and it will be loud), install high flow cats.

 

[John Johns]

Try it and see how you like it. You can always change it until you get it the way you want. I've had a number of exhaust setups on my 97 and finally went with Borla headers and catless back, with Dynomax race bullets in place of the Borla mufflers. Probably too loud for most, expecially at wot! I like it.

 

[John Johns]

The x or h pipe at the rear adds a nice tuned sound. Just had mine done.

 

[v10kingsnake]

remove those cats. take it from me, a person that has had them off now for months. you lose the heat, gain some hp, awesome REALLY noticable lumpy cam idle as a bonus. it is louder but a good loud. I have a borla exhaust cat back and they are known as being the louder system out there but you can ask anyone that has heard the car idle and drive, TAXIMAN1 (ron) that it sounds awesome. i have heard that power can be digured in the 10-15 rwhp range by cutting these cats out. I believe it fully. i can also tell you that i cut my cats out myself with a sawzall and they weigh every bit of 30 lbs at least EACH!!!

 

[v10kingsnake]

oh and you absolutely will not have any, i repeat any issues with a check engine light coming on in a 97 by just removing the cats.

 

[Bob K]

I removed the cats a couple of weeks ago (have headers and Borla cat back) and I have noticed three things:

1. It is very loud and lumpy at idle and mass loud at WOT
2. There is a noticeable exhaust smell
3. The side sills remain cool - I took a 20 mile spirited drive yesterday and the sills were not even warm

Bob K

 

[Eric H]

I removed my cats, and removed the mufflers from the rear and replaced with a single oval tip, but kept the resonators in the side sills, sounds great but it is much louder than stock

no codes on my 98

 

[New97owner]

OK, it sounds like the cats definately have to go...if I get rid of the rear muffler, and leave the resonators, will they still hold additional heat in the sills, or would there not be much heat difference in resonators versus no resonators? Thanks for the replies, guys, as I hope to do something about this next week...
Mike

 

[LETHAL GTS]

I have a borla exhaust cat back and they are known as being the louder system out there but you can ask anyone that has heard the car idle and drive,

Sorry, the B&B is much louder.
I work on and store my buddys 2000 RT/10 and we cruise around alot together. We have the exact same mods for the last year. The only difference was our cat back systems. His being Borla and mine being B&B. He still can't hear his car when I'm around. Now that I have added the RR's, my car has gotten a snappier sound and maybe even a little louder. 149db to be exact.
He is planning on removing the rear mufflers that come with the Borla system just so he can hear his shift points when we race LOL
His does have a deeper throatier sound than mine though.

Corsa is the quietest followed by Borla and then B&B.

 

[GTSPOWERED]

I have removed the cats and the rear muffler and love the change in idle and heat removal. I am wondering what the diffrence in removing the muffler / cats and removing the resonators / cats would be? What the sound change would be.

Patrick Mathias

 

[LETHAL GTS]

OK, it sounds like the cats definately have to go...if I get rid of the rear muffler, and leave the resonators, will they still hold additional heat in the sills, or would there not be much heat difference in resonators versus no resonators? Thanks for the replies, guys, as I hope to do something about this next week...
Mike

As long as you dump the cats, you will notice a significant drop in side sill temps.
Personally I think the route you're going is better than leaving the rear **** in and deleting the resenators. The x or H pipe is a must though. Otherwise people will think there is a tractor coming down the road. OK not that bad, but you won't be pleased without it. It balances the exhaust note.

 

[v10kingsnake]

I have a borla exhaust cat back and they are known as being the louder system out there but you can ask anyone that has heard the car idle and drive,

Sorry, the B&B is much louder.
I work on and store my buddys 2000 RT/10 and we cruise around alot together. We have the exact same mods for the last year. The only difference was our cat back systems. His being Borla and mine being B&B. He still can't hear his car when I'm around. Now that I have added the RR's, my car has gotten a snappier sound and maybe even a little louder. 149db to be exact.
He is planning on removing the rear mufflers that come with the Borla system just so he can hear his shift points when we race LOL
His does have a deeper throatier sound than mine though.

Corsa is the quietest followed by Borla and then B&B.

i have heard rumors that borla has changed its design in the not so recent past. and the word is the newer design is much quieter than the old system. i have had my system for awhile now so i am pretty sure it is the original, untainable now system. the newer ones i believe, and i use this term losely is quieter because it has resonators out back where-as mine is straight pipe after the mufflers in the sill. maybe your friend has the newer system. i always used to hear eeryone on this board either rave or hate the old borla for its extreme loudness over the other systems. please correct me if i am wrong

 

[Viper23]

I have the cats removed on my 96 Blue and white and it sounds awesome. i actually got the car that way. My friend who sold me the car did it himself. I also have Borla and headers and that car sounds like a beast. Also, the side sills are very cool after a hard day of driving. I also have an R/T 10 with HF cats and I ger burned everytime I get out of the car.

So I would highly suggest it.
Be

 

[Toby]

I have a borla exhaust cat back and they are known as being the louder system out there but you can ask anyone that has heard the car idle and drive,

Sorry, the B&B is much louder.
I work on and store my buddys 2000 RT/10 and we cruise around alot together. We have the exact same mods for the last year. The only difference was our cat back systems. His being Borla and mine being B&B. He still can't hear his car when I'm around. Now that I have added the RR's, my car has gotten a snappier sound and maybe even a little louder. 149db to be exact.
He is planning on removing the rear mufflers that come with the Borla system just so he can hear his shift points when we race LOL
His does have a deeper throatier sound than mine though.

Corsa is the quietest followed by Borla and then B&B.

i have heard rumors that borla has changed its design in the not so recent past. and the word is the newer design is much quieter than the old system. i have had my system for awhile now so i am pretty sure it is the original, untainable now system. the newer ones i believe, and i use this term losely is quieter because it has resonators out back where-as mine is straight pipe after the mufflers in the sill. maybe your friend has the newer system. i always used to hear eeryone on this board either rave or hate the old borla for its extreme loudness over the other systems. please correct me if i am wrong

The newer Borla system is quiet compared to the older set up.

I have had both.

 

[JonB]

Pros and Cons are all relative, and most to the YEAR of the car, and the part!

1) Borla indeed has dramatically revised their cat-back in the last few months.

2) So you heard a CORSA, did ya? They were waaay different 96-01 than 01-05.
What year did you hear?

3) Your 97 DID come with 2F and 2R Oxy Sensors, despite what someone stated.

4) They will NOT throw a CEL code in your 97 if you go catless.

5) Catless SOUND depends on the other plumbing you choose. Catless OE many folks say results in a ratty sound. Catless usually generates backfiring (and even flames)if there are no mufflers/resonators aft of the headers. Catless pours out 8L of STINK every 2 rpms. You could lose some torque. Many folks go catless, and return to stop the stink. Especially w/ sidepipers.

6) Crossovers or H-pipes do diminish resonance, drone, and some backfiring. They are too far back in Gen 1-2 to save torque.

7)Every time you reduce restrictions (headers, bends, cats, resonators, mufflers,crossovers, larger tubing, etc)you COOOL the system a bit more.

7) HiFlow cats run WAY COOLER than OE cats and result in 125-150 degrees cooler sills. The higher their flow rate the cooler and louder they are. And they dont stink like catless. And they dont backfire. They do "burble". They do allow the rear Oxys to do their job and send problem messages IF THERE IS A PROBLEM

 

[Shelby3]

I have the new Borla cat back (rear mufflers removed) and don't like it nearly as much as the old system. Not as loud at low rpm's and has a ratty sound. I'm thinking of losing the resonators and going with some high flow cats and nothing else.

 

[v10kingsnake]

i knew i heard correct on the borla.

 

[LETHAL GTS]

I have the new Borla cat back (rear mufflers removed) and don't like it nearly as much as the old system. Not as loud at low rpm's and has a ratty sound. I'm thinking of losing the resonators and going with some high flow cats and nothing else.

Have you heard the Newer B&B (newer has the x pipe) without cats and how would it compare to the old Borla?
Maybe Jon could comment on this as well.
My buddy was talking about removing the rear mufflers. How much difference did that make?

 

[vipeuup]

All I did was put on high flow cats.Left everything else stock. Just the high flow cats alone. made it alot noiser. Especially on the freeway. Again, didnt really cool down the sill or cabin too much. I just cant imagine deleting the cat , resonator and just having a straight pipe. crazy loud For just doing the cats. Big power gains. The stock cats sure do choke that V10 engine.


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[Leslie]

what about with an '01 GTS?

I just put the corsa's on, and it's not loud enough for me

 

[GTS Bruce]

Leslie.Get rid of the cats and use a straight pipe.Will need cat syms and will sound like Lemans when you're on it.The corsa system by itself was a disappointment for me. GTS Bruce

 

[Shelby3]

what about with an '01 GTS?

I just put the corsa's on, and it's not loud enough for me

Corsa's are for chicks. Get the old Borla or the B&B. 2MANYTOYS has the only Corsa I've ever heard that sounds like a Viper should and I don't know how he does it.

 

[Shelby3]

I have the new Borla cat back (rear mufflers removed) and don't like it nearly as much as the old system. Not as loud at low rpm's and has a ratty sound. I'm thinking of losing the resonators and going with some high flow cats and nothing else.

Have you heard the Newer B&B (newer has the x pipe) without cats and how would it compare to the old Borla?
Maybe Jon could comment on this as well.
My buddy was talking about removing the rear mufflers. How much difference did that make?

Rear muffler removal on the new Borla is noticeably louder but has a ratty sound. Nasty loud at WOT

 

[SYNFULL]

I have the cats removed with Belanger headers and Randomtech Exhaust. If you are considering an exhaust system check out the Randomtech's. I think they can't be beat. They sound great, have the crossover, look beautiful, and cost less than all the others.

 

[vipeuup]

I have the cats removed with Belanger headers and Randomtech Exhaust. If you are considering an exhaust system check out the Randomtech's. I think they can't be beat. They sound great, have the crossover, look beautiful, and cost less than all the others.

Syn,

Did you buy the Randomtechs from Parts Rack?

 

[vipeuup]

what about with an '01 GTS?

I just put the corsa's on, and it's not loud enough for me

Damn. not loud enough?? You got music to your ears. HA HA