il shall be making and fitting a side exit exhaust to my clio/volvo engine the down pipe that il be modding is off a 200sx and is 3 inch il be fiting it to a normal clio exhasut which is about 2 1/2 inches is this going to make a loss in power as i want to fit my silenced decat and maybe cat for mot time also are there any tips ect i can buy to weld onto the end of the pipe ones ive finished it what do you guys do cheers