most people seem to decat then put on an 'after market' back box...

is there any particular reson for this or could you keep the orginal silencer and just take the cat out...surly doing this alone will still change performance and noise :confused:

Joel

A little (incy-wincy) bit yes but the std exhaust is complete rubbish when compared to after market items which are properly gas-flowed etc.

I wonder if it is worth it "just" to remove the standard cat and retain the standard dp and cat back.

After all the down-pipe and cat are a single item so the cat would have to be cut off. You then need to get a sleeve made up to replace the cat and connect upto the standard exhaust.

I'm sure you'll get some gain from the cat removal but is the sleeve going to effect the flow?

I know Colin had a decat with standard dp and a Powerflow cat back.

Perhaps a wise old Sage can enlighten us on this.

Chap before me had taken it to powerflow, who basically cut the OEM cat out and fitted a tube. They also fitted a different back box which gave it the boom, fine below 60 and fine above 90...inbetween made for headaches after 5 hours of driving.

But it retained orignial pipework, downpipe out to the backbox where it of course changed.