GenIII Secondary cat gutting

[JLorello]

Is there any issues to doing this as a permenant mod? The High-flow cats don't use secondaries either I believe.

Can they be removed without a CEL?
Still pass emisions?
Why doesn't this seem to be common?

Any other thoughts are welcome!

Thanks.

 

[plumcrazy]

its not as easy a it sounds, they are built pretty good. it will throw a CEL

 

[bluesrt]

yep on the cel light

 

[steve911]

If you gut the SECONDARY CATS on a Gen 3 it will NOT throw a CEL. All of the engine monitoring takes place before the secondary cat. Both my '04 and '06 have been gutted, no problems. I have assisted 9 other viper owners with the same procedure without a CEL.

The secondatry cats are a metal substrate instead of the ceramic like the primaries are. It takes a bit of effort, and as Plum says they are built well. You will like the sound after the "gutting".

 

[snakem04]

I have a aftermarket race exhaust with no cats. My sensors are coiled up in ziplock bags on each sensor and then ziptied up and out of the way of the exhaust. Never had a cel since i did the job over a year ago. No problems.

 

[BLK04]

I have headers ,3" hi-flo cats & corsa exhaust ..got a cel,deleted it & it came right back. O2's are still conected but ziptied out of the way...sims to go on in the spring

 

[AbsolutHank]

I have them gutted on my Gen III, with a Corsa catback...stock manifolds and crossover deleted obviously, and never had a CEL on...ever

 

[agdetail]

i saw some pictures of the cats and i think they are welded together. why not remove both, buy o2 sims, and get some stainless tubing.

then if its not enough, get american racing headers.

im about to gut both mine out after i pass my emissions test next year.

 

[plumcrazy]

used cats are worth a few bucks these days. (last i heard 75-100 bucks) you might wanna consider throwing a cheap $30 pipe in their place

 

[Camfab]

used cats are worth a few bucks these days. (last i heard 75-100 bucks) you might wanna consider throwing a cheap $30 pipe in their place

I agree here, why would you destroy a perfect set of cats? Just replace them with some stainless pipe, it's not a 1975 Impala guys. Boy things have changed around here, I remember when everyone was so concerned about every minute detail. Now we got guys talking about hacking their cats with screw drivers in their driveways..........................

 

[Viper Specialty]

There is next to ZERO net effect on gutting a secondary G3/4 cat. The secondary cat is much higher flowing than the primary, and is not the weakest link in the system. With that said, it is also a VERY nice cat, do not gut them of throw them out! hell, I would give you a few bucks for them.

 

[Viper Specialty]

I agree here, why would you destroy a perfect set of cats? Just replace them with some stainless pipe, it's not a 1975 Impala guys. Boy things have changed around here, I remember when everyone was so concerned about every minute detail. Now we got guys talking about hacking their cats with screw drivers in their driveways..........................

Ain't it the truth? I have my fingers crossed that the Viper market doesn't go the way of the Corvette and Camaro market, but I fear the writing is on the wall with the way our economy is in the crapper and these car prices keep falling. Also one of the reasons that I refuse to get into the "battle of the bolt-ons" aspect of this market... just wait until some more hacker-shops get their hands on Vipers because the new owners don't know any better or care anymore, then you better believe every easy to get Viper part will be selling for 1$ over cost with ZERO support like every other domestic part.

 

[georgethedog]

Guess it is not an "exclusive" club anymore. I think that if people hack on a Viper they bought that so be it. It only makes the "well kept" close to stock ones more valuable in the long run. It's a free country and a free market, so I say let the market dictate. As a business professor it is funny to me watch again and again people who are all for the "market" until the market forces screw with their world...

 

[Camfab]

Sorry guys I don't mean to sound like a snob. I just think it's crazy to do that, it's a costly high quality part. Merry Christmas and Happy New Year to everyone.................or Happy Hannukah or whatever you celebrate.............enjoy the rest of the year.

 

[Twister]

Wow. Its a cat. Big deal. Cut it outand replace with straight pipe and keep it in the garage. I picked up a mph in the quarter when I deletedmy secondary cat. Car rac kooler and sounded nicer.

Its a 90k dodge. Not a 250k ferrari. Do whatever you want to it. Its no biggie. Just metal rubber and plastic

 

[JLorello]

Wow, I am surprised by some of the comments in this thread.

I never stated or intended on doing this, just wanted to open a discussion about the effects/pro's/con's. Coming from the 3000gt world, cat gutting is an extremely popular modification due to the decreased resulting backpressure. Granted, that is coming from a turbo car, not a naturally aspirated one.

After researching hi-flow cats, without the secondary’s, I simply wanted to learn about the effects of the above on the viper platform. I apologize for offending anyone. I will not be "hacking" up one of our precious cars...

Moderators, please close/delete this thread.

 

[georgethedog]

I would call Jon B at Parts Rack on this one. Not only is he an expert on such matters, but he is a 3000GT guy and would understand the situation from your perspective.

 

[bluesrt]

you can acually rob your lower end torque by doing this on a factory tuned car- and will make it faster more hp on higher rpm top end, so if you wanna run the bonnville salt flats,gut them, other wise dont cause you will kill engine performance for normal spirited drives