Removing catalyst breakup from exhaust.

[Rawhide]

My car has now had a new clutch, slave and flywheel. It's in rude health but I'm told the catalyst had been breaking up and now the backbox is rattling. It sounds fine whilst driving but at idle you can hear stuff rattling around.

I'm not keen on more volume so don't want to replace the exhaust. It's already too loud for my liking so I'd like to try and get the pieces out.

Does anyone know how the exhaust back box baffles are laid out? I don't want to have to remove the back box to find I can't shake the stuff out.

Anyone else managed to do this?

[good40]

Are you sure its the cats gone, maybe just the baffles in the exhaust loose?

[robsco]

I had the baffles taken out of my standard backbox when they started rattling as a temporary measure. Think of a great big hole being cut out of the exhaust and then re-welded up afterwards, and you're there. Be warned though, a standard backbox with no baffles is extremely loud, and not a pleasant loud either. I drove mine 10 miles and had a banging headache when I got home.

[Rawhide]

It was Jason at Str8six that it was the cats that had broken down. I was going to have him refit them as I prefered the lower volume that with it decatted but he said they were no good so advised to leave them out. He did try and shake the debris out and I don't think it was there before the clutch was done but it does sound like small pieces rattling around and only at tickover.

I might look for second hand back boxes instead. I'd like to keep the car track ready and don't like the drone I'm getting on the motorway.

[good40]

Rawhide said:

but he said they were no good so advised to leave them out.

http://www.ebay.co.uk/itm/TVR-Cerbera-4-5-Catalyti...

[robsco]

good40 said:

http://www.ebay.co.uk/itm/TVR-Cerbera-4-5-Catalyti...

Why the shake of the finger? What advantages are there to running a Cerbera with cats? As far as I can tell, they offer dreadful heatsoak into the cabin, increase fuel consumption and mute the exhaust note (admittedly the OP sees that as a good thing).

[Olly]

A cheaper alternative to new CATS (as long as you have a friendly MOT garage), is the ACT de-cat silencers.

We have them on our car - makes it almost civilised up to about 3500rpm, but beyond that, it's gets very throaty ! (helped even more by having sports pipes)