A mate of mine has just bought an S3 with an mrc stage2 map using a Miltek de-cat. He doesn't like the sound so has reinstalled the stock cat/downpipe, I told him he would need a remap or at least a map tweek. He then rang MRC and the girl on the phone said it would be fine. I'm surprised at this and would of thought the cat would not cope with the flow needed now. The cars running 410bhp.