Chris3620

I have a '96 C2 w/ Varioram and (4) 02 sensors that are plugged into the stock OEM catalytic converter. Recently, I switched to RSR mufflers and was very pleased at the fact that the car ran cooler, sounded better and ran through the revs more smoothly. Taking that thinking a step further, has anyone out there replaced the 400 cell stock catalytic converter inserts w/ a more contemporary and aggressive 100-200 cell units?? I know it can be done; replacing the cc inserts while retaining the stock cannister; does anyone do it?

Thanks, Chris

TargaTango

Chris,

"If there is one static blockage in the whole 993 exhaust system it's the catalytic core." from p512 of Adrian Streather's marvellous "Porsche 993 The Essential Companion".

People indeed do swap standard cats for 100 cell cats. This is part of the Ninemeister upgrade which I have undertaken. Without it the full advantages from their revised cylinder heads cannot be achieved. I am not sure however what advantages are gained from swapping the cats alone. I would have thought that there would be an advantage but whether you then need a revised engine chip to take full advantage, I do not know. This is not an inexpensive upgrade. Try doing a search for more info.

As to sound, I am running stock mufflers and the 100 cell cats do change the sound. To my ears it is not a particularly melodeous one. But it is the business rather than a "cosmetic" muffler change.

All the best,

Caveman

Ive seen a car that has had the cores swapped. Mark Budgen has a supercharger fitted and needed more flow so had this done. It was a simple cut and shut job. Do a search on him and this will come up. I have cargraphic 100 cell cats fitted and got a decent improvement from them. My expectation is that I'll get a bit more when I get round to getting my chip remapped.

Cheers,

David

MPB993

Chris,

as David says I needed to change my cat as a result of adding the SC which ended up limited by the flow of the standard unit.. The cat was removed and 100 cell canisters added. I have had it that way now for about 30k miles. Passed uk MOT emissions so I haven't seen any down side.

Cheers, Mark.

Caveman

Hi Mark,

Long time no hear. I hope you are well. Have you seen our proposed meet over on the 964 forum?

Cheers,

David

jdistefa

How about just dumping the stock cat (heavy) and replacing it with either DACH-X 200 cell cat pipes, or the similar Fabspeed product. Either will run you around $1600 USD.

993inNC

DACH - $1450

jdistefa

Oops, my bad.

993inNC

No worries.......I'll take $1600 though

MPB993

Dave,

just got back from a trip and missed your post. Unfortunately I cannot make the drive this Sunday but I'm sure you will all have fun. Post some pictures so that I can see what I've missed. My car continues to get better with age and miles or is that just me getting older.

Mark.

Wilder

If you don't have emissions testing in GA, have you considered going with cat bypasses? I recently bought Chirs' DACH X pipes and though loud, they're quieter than I thought they would be...and that's with RSRs. There is a thread where another RLer dyno'd Chris' DACH bypasses and there was an 8HP gain, not to mention the great benefits of that sweet sound.

BTW, I have emissions testing every two years here in BC. I kept my cats so I can swap for testing in two years.

CarreraX

Has anyone ever just gutted the cat? As some of you may have read, my 993 had a runability issue that turned out to be a clogged cat. I swapped it out with a used one from a friend. I was thinking about cutting the side off and gutting it and welding it back shut. Has this been done before? Thanks, Mark