hey have my second defect inspection tomorrow not sure if i will pass,
not too long ago purchased a 5" HKS hi power catback exhaust system for a series 2 R33 gts-25t went straight in un restricted and @ 3,300 rpm it read at 97db but on the side i was only revving it roughly at 3k had a 1-2mm peice of sheet metal with a 30mm hole or so drilled into it so it can restrict the flow... now the exhaust seems a bit loud and it has to be 90db at 3,300rpm any ideas on a quick silence fix i been told to chuck a piece of chicken wire inside?
any ideas much appreciated