Now i have the exhaust fitted i tested it out and the car doesn't change gear smoothly any more. Once it goes to around 5000 reves it jumps up and down between 1st and 2nd causing the car to judder. Have tried using gears on steering wheel the same problem. Any one come accross this. The car was fine until i fitted the new exhaust, will it have something to do with the ECU unit? I was told to dissconnect the batteryt for an hour or so so it would reset but it doesn't seem to have worked. Seems pointless having a performance exhaust if it reduces it. Any feedback or suggestions are most welcome