Clogged High Flow Cat

[96GTS]

I have a 1996 GTS, and the side sill on the driver's side has bubbled/blistered in the area where the high flow cat is located. It's a Random Tech, and it's been on the car since I got it 7 years ago. After driving it for a while it's very hot to the touch, it this an indication of a clogged cat?

 

[tlcobra]

Could be cat my car did it last week it was a o2 sensor. Try swaping the left for the right see if other side gets hot. If you have a scan tool you will maybe see fuel trim at -25% or more on the bank that is hot. If its 02 dont buy bosch

 

[Allan]

Why do you guys bother with cats at all?

 

[GTLaser]

Why do you guys bother with cats at all?

Exactly.... My high flows are coming off this week and going up for sale.

 

[Allan]

Right on! -empty pipe flows a lot better than any kind of cat and it will never plug up.

 

[klamathpro]

Why do you guys bother with cats at all?

Because Vipers sound like crap without them. Every catless Viper I have ever heard sounds ricey and too raspy. A guy at a local car show brought a GTS with Striker heads and headers with a (supposedly) expensive Corsa exhaust without cats. Sounded like crap when he revved it without a load. I left the show and went over to another car show. An hour later I hear a what sounded like a Rice Burner Honda Civic fly past me... Looked up, and it was him. Yes, it was very loud, but not a quality exhaust note.

I know it flows more and I'm gonna get razzed for saying this, but I'm sorry, I have yet to hear a truly great sounding catless Viper. It just doesn't sound the best without high-flo cats on our V10. Nearly every person that has heard them say my two Vipers have the best sounding exhausts on any Vipers, all years. Roe catback on the RT/10 and B&B on the GTS, both with high-flo cats. I need to record and upload clips sometime. I seriously bought my GTS soley on the exhaust note alone. Never heard anything that perfect before on a Viper.

I say, unless you need to run leaded race fuel, stick with high flow cats.

 

[MTGTS]

Don't get me started on Random Tech. You can do a search for a thread I start awhile ago and see the outcome.

 

[ViperTony]

Could be a clogged cat, bad O2 sensor, bad tune, exhaust leak, etc. as others have posted. I'd have it all checked out. Scan the O2 output to see what's going on with them. If it's a clogged cat something must have contributed to the clog. I suspect something on that engine bank may be contributing to the issue. I'm not a fan of RT cats but I have ceramic RT cats on mine since '06 and no issues. Coincidentally, I completed some exhaust work over the weekend and checked my cats just in case (in part due to MTGTS RT thread from way back) and they're fine.

Do you notice a difference at the tailpipes meaning that one pushes out more exhaust than the other?

 

[96GTS]

Thank you everyone for the information, I'll start there.

 

[Leslie]

I was not sure how mine would sound too without my highflows, but mine sounds great!
I have corsa exhaust.

I hear the high flows don't last but a few yrs...mine were toasted.

 

[Detlef]

Leslie, what did you put in after you took out the CATs? Just a straight pipes and O2 sims? Are you shooting flames on downshifts ?

 

[Leslie]

haha dang, now Shandon IS shooting flames, will have to find that pic.

I hooked up with a local NASA racer (Ray Sweers) and he had his mechanic take my side sills off, then drove me over to the muffler shop he uses.
Before with high flows, had been on 5 years

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without cats, straight pipe, $50

You must be registered for see images attach

 

[GTLaser]

Well my old school Borla sounds amazing with my current set up, my cats toasted my side sills so I put on hi-flows. I'm removing them because I'm putting on my Belangers and want bigger sound so I opted to remove the cats from everyones recommendation, we will see that happens.

 

[Detlef]

Cool, but did you put in O2 sims as well? I ask because we have the same year GTS.

 

[Leslie]

No I havn't

 

[96GTS]

The 1996 GTS doesn't need O2 Sims...correct?

 

[costanZo]

My car is currently getting a bunch of things installed at A&C, and in the process my Random Tech High Flow cats are going to be removed too.

My full exhaust will be American Racing Headers, straight pipes, and Corsa. Can't wait to get the car back and hear how it sounds!

 

[eucharistos]

Why do you guys bother with cats at all?

sniffer test every year in my county