Fabspeed secondary cat bypass

[wgkins]

I am considering replacing the secondary cats on my 02 S using the Fabspeed bypass pipe. I'm looking for better sounding exhaust note (factory system too quiet). Has anyone just replaced the secondary cats and how did it change the exhaust note and were there any other issues to be concerned with? I don't care to go to the expense of replacing the muffler and I was thinking of this as an option.

[adsach]

For a budget solution, you can remove the muffler-leaving the 2nd CATS on the car- disconnecting at the sleeves. If you cut off the top of the muffler, remove some of the insides and reweld the top closed, you will have a louder- lighter muffler. I imagine a muffler shop would do this fairly cheaply as it shouldn't take more than 1-2 hours labor.

I doubt the sound improvement would be worth the headache of seperating the pre-cats from the cats.

If you replace the secondary cats with a bypass pipe, be prepared to replace most of the bolts/studs at the trianglar connector. These will probably be rusted into junk. Getting out the old broken studs and bolts will probably require removing the whole exhaust- headers to tailpipe - and banging on your triangular flanges with a hammer.

Sleeves (left) good - triangular flange (right) bad

sleeve

Replacing the muffler is less of a headache since the sleeves between the 2nd CATS and the muffler are held on with carriage bolts and clamps. Busted carriage bolts are much easier to replace than busted studs. The hardest part to removing the muffler is figuring out where the upper hanger bolts are(out of sight between muffler and transaxle).

2002S muffler bracket - on muffler

2002S muffler bracket - on transaxle

2002S muffler bracket - the wrench I used

Edited October 12, 2005 by adsach

[navin in KC]

You could even buy someone's exhaust that they've had removed to have a shop work on it and then just put it on yourself.

For example, I (and probably many others) have removed my stock exhaust from my 2004 C4S, so I could put on the Sport Exhaust. The two mufflers are sitting in my attic looking for something to do right now. They are pretty lonely up there.

Just a thought.

[Gundo]

And rather than adding the cat bypass pipes, just stick a metal rod down the secondary cats to break up the obstruction catalytic element, then vacuum out.

I have not done this and do not advocate it, but it certainly is a cheaper and easier option than buying the fabspeed bypass pipes.

[adsach]

And rather than adding the cat bypass pipes, just stick a metal rod down the secondary cats to break up the obstruction catalytic element, then vacuum out. 

I have not done this and do not advocate it, but it certainly is a cheaper and easier option than buying the fabspeed bypass pipes.

<{POST_SNAPBACK}>

Interesting idea Gundo

It certainly would be easier. All you would have to remove is the sleeve clamps and jam a rod down the exposed tube. The muffler and CATs could stay on the car.

I wouldn't do it either. Destroying a catalytic converter sort of negates a lifetime of recycling.

There is a risk of adding a rattle of broken parts to the exhaust sound.

[tjkrueger]

I also have an '02 Boxster S and have installed the Fabspeed Bypass pipes and changed the muffler to a Remus (purchased from Brandywine on Ebay). I think that it sounds great not to loud but has a nice aggressive tone to it. I'll save the cat so if I decide to sell it, it could be put back to stock. I've had others drive or DE instructors ride in my car and they say it feels very strong. They are surprised at it's performance. I've also install a light weight flywheel in it so that helps too. Tom