Hi, I have a C6 Vette with auto trans in Karachi, Pakistan. I wanted to know what will happened if I take out the cats; thats if anything negative?

Plus is there anything I can do to increase the sound? also, how much of a horsepower gain will I get after removing the cats? No worries about emission laws here :-)

I will appreciate if anyone would answer one or all of my queries.

Thanks,
&
Best Regards,

Abul

 

The engine will throw service warning codes and you will experience strong exhaust odors on start up and shut down. Your vehicle will require a new tune in order to optimize it's performance.

Not sure it would be worth the trouble.

 

Do you see any other Corvettes there?

 

You can eliminate the codes but IMO just removing the cats on a stock C6 isn't going to accomplish much. If you want a little extra power I suggest long tube headers and an after market exhaust. An exhaust is not a performance mod per se but coupled with headers you'll notice a bump in power. After market exhausts (such as Corsa or Borla) often use after market, 2-stage cats or use no cats at all. Lots of guys run without cats and don't suffer warning codes or bad odors. I'm not a big fan of mail order tuning but many guys do it. Good luck!

 

Agreed, keep the cats and add long tubes, and maybe a cam ... "VROOM"

 

I disagree with everyone.

Remove them and enjoy. Once you have a tune you shouldn't smell anything.

I haven't had cats on any vehicle in the last 7 years and wouldn't change it.

 

The engine and its computer system are designed to use the cats. Lots of effort will be required to make it run right without them...and for very little benefit. Cats now and the computers that run everything are very different than in 1975 when they were introduced. Cats are no longer the strangling restriction that they were in the past

 

Hey guys,

Thank you for the replies. This is the first time I have joined any forums, one for my Vette and one for the ML63 I have. It’s really nice to know that there are enthusiasts who take the time out to reply to fellow enthusiast’s questions / concerns.

Turbod has said that the car will have odors at start up and shut off, that is not a issue, plus I never noticed it when I removed them from a Dodge Stealth I had, like some 17 years ago, but then I don’t have a enclosed garage: what I did, and what I have in mind for the Vette, is that I remove the cats, breakout/hammer out the ceramic/chemical element out of it, and put the assembly back without the actual element inside it: but if it requires a re-tune, then I cant do that here, re-tune that is.

To answer MadMax: yes there are a few Vettes in Pakistan. There is a string ray from 1970s or around there, a 1980, a couple of C5s and a few C6s, and two Z06. and yes there is a C4 I imported in 1996. I use to own a Viper GTS as well, it’s now in Islamabad, and the guy who bought it said that there was a major increase in horsepower after he removed the cats.

Wayne O: Buddy thanks for your advice, and I may be wrong, but I think in the US they have these after market exhausts so people can be street legal, but then I said that here in Pakistan we don’t have such issues  sad, but for us car lovers its okay, we have bigger issues otherwise  but then as he said, if there isn’t much of a gain in horsepower, then why do it? I thought that after removing the cats one gets at least a 5-7% gain??

Thrash: not sure what long tubes are, but I can have straight pipes, but then that would be too loud, not that I go for hours long drives in Karachi, but still 

FloydSummerOf68: I like your attitude; do you have any Paki blood in you?  I hope this does not start a racial issue here  That’s what my plan is, but then you mentioned re-tune, I don’t think I can do it here; what kind of equipment does a re-tune require?

Cclive: That is my concern as well; what will the computer do if I take out the cats, the way I will be taking them out?

Once again, thanks for your advice.

I look forward to hearing from all of you.

Abul

 

Abul, this is the Longtube headers, high flow cats, and x pipe I just installed.



As you can see quite a bit of difference from the Chevy stuff I pulled off.



My car before the work:



Car after the work:




Smoke was from the new pipes etc....

 

Wow! that was a quick reply! thanks, but to be honest, after hearing the sound on the video, your stock Vette sounds better then my stock Vette at start up. was that a C5?

 

In the pics the size of the cats is bigger than the stock cats, but here i can completely get rid of the element inside of it? what do you say?

 

Glad your doing your part for clean air ! The very minor HP loss (If any) from the cats does not out way the bigger picture of lower emissions and social responsability we all share in keeping the air, If not clean, then at least a little less dirty. JMHO

 

In this case-size doesn't matter. The GM cat has more element than the high flow cats do. I wish I had a pic down the tubes to show you. My car has NPP exhaust so I have the flaps open. I just don't think you are going to get what you are looking for just by removing the cat element. The restrictive part of the exhaust is the header itself.

 

NPP is a stock exhaust that can either run through mufflers or straight through. It is a vacuum operated system that once the car is at 3500 RPM,will open the flaps and run straight exhaust. Or, if you are like me, buy a system to turn them on and off at my choosing.

To get more HP and sound, It would be cheaper and easier to buy and install an aftermarket catback exhaust like Borla or Magnaflow rather than spend time trying to beat the media out of the stock cats.

I live near Washington DC. :

 

sorry to go off topic but it would be nice to see pictures of the car with some of the historic buildings as a back drop, nice contrast!

 

Hey Buddy,

It’s really nice of you to keep replying to my queries/concerns. So the NPP is a stock system? Mine is a 2008 car with 1800 miles on it now. Maybe you missed out on reading that I am here in Karachi, Pakistan, no Chevy dealers, and no after market people for such cars: there are a few who are into supping up Japanese cars, but like a less than 10 and that also only for Mitsubishi EVOs, Hondas, Supras etc.

I can order a catback exhaust like Borla or Magnaflow, but I can get things done here in Karachi which would cost me like 100 dollars or so for what I want, and its not really about the money, but with no emission laws to worry about; what are my best options? I need a bit more of horsepower n sound?

 

Madmax, sure, but please tell me how to add images?

 

I understand your situation. I just don't think you'll get much "bang for your buck" by having someone take the media out of your cats. Catalytic converters are pretty efficient. Most sound is killed by the mufflers. Maybe you can have someone do something with those instead of the cats.

 

pls see my respone message on your profile

 

Vatorman, your header/exhaust looks polished, what system are you running, I see a kooks box but don't want to assume. Thanks system looks great.
Thanks