Hi all,

I am driving a 997 C2S with 100 cell cats and Cargraphic exos,i am toying with the idea of taking out the sports cats and replace with a bypass pipes,however i am worried abt the low end torque,can anyone offer me some valuable advice on this b4 i make a jump for it,many tks in advance!!

Turbo S

 

Removing the catalytics will cause check engine lights and the car will not pass emission inspections. Sport catalytics are said to cause about 4 hp power reduction. Looks like a bad idea, spend money & make the car unable to pass inspection for an incremental power gain.

 

Just my personal opinion..

But, i HATE the way these cars sound with cat deletes. Even with low cell cats you take the edge off the rasp. But remove the cats, and the crackle is just too much for me.

I think these cars sound best with a set of headers, low cell cats, and stock cans.

 

Are you saying that a sports cat will cause reduction to the power?So basically,the job of the sports cat is to add sound and reduce power,am i correct?Tks for enlightening.

 

But i have known frens that has gotten sports cats and stock mufflers and the stock mufflers just gave way after sometime i was told.

 

You misunderstood my remark, or maybe I wasn't clear. Sport catalytics increase power over stock parts, probably more than the headers or muffler. Stock cats are very restrictive. Cat delete pipes will only get about 4 hp more.

 

I have 200 cel cats and muffler bypass pipes, sounds insane and pulls like a **** on the highway

 

Like to hear that car with fabspeed bypass and 200 cel cats. Must be like a freight train .

 

I see dude,so maybe its has gotta do with either there are too much flow or the flow has been choke by my mufflers,i shall remove the mufflers and experience with mufflers bypass and see how it goes,tks again

 

And how does it feel when you are doing urban?Does yr car suffer from flatter low end?Tks in advance.

 

Muffler deletes are extremely loud and produce maybe 5 hp more. The car will be obnoxiously loud and attract the unwelcome attention of your neighbors and the police. Your friends won't ride with you, unless they are hard of hearing. Put on an aftermarket muffler or PSE.

 

Hmm, all of this stuff sounds like a lot of guess work and potential iffy results.

The best mod I've found thus far is to add a set of AH pipes, leave stock cats / headers on and be happy. I just posted dyno results + vids and it made a big difference in gains on TQ / HP across the band, and of course it sounds insane. Same thing on my 996. Simple, not expensive, easy to DIY, and reliable. This is what worked good for me and fit my goals.

Before you start changing things and investing time / money based on guesswork, figure out what your goal is.

For example:
Do you want louder sound than stock but don't care about more HP/TQ?
Do you want slightly more HP/TQ and a bit louder sound than stock?
Do you want max HP/TQ and loud, agressive, cup car sound?
Do you want jet-airplane loud and don't care about losing HP/TQ?
> These are all possible directions to go in depending on what you buy / change.

We have a number of excellent site sponsors who specialize in exhaust systems, so depending on what your goals are, talk to the vendors and get the hard facts first. It will save you some time and expense, and help you with picking up the right parts the first time around.

 

Muffler bypass pipes = loss of Torque. Not a performance enhancing mod.

 

Tks for yr advice,however i wonder if AH can send what you have to me the otherside of the globe and how ouch its going cost me.Currently i have Awe 200 cells and Cargraphic on mine.nd mine ride is a TIP not stick,i wonder if theres a great diff...

 

Just call and ask for Brian (owner) - really nice guy, he has shipped quite a few sets internationally. Number is on website www.afterhoursautomotive.com

My 996 was a tiptronic, the AH pipes were a great help with the taller gears / 5-speed, car had a lot more pull off the line.

Remember you get a $50 discount if you ask for the "forum price".