hey hey, X-Force Twin loop S10/12 are a great muffler to buy! They are approximately 2.5inches and provide a very nice note. they can go up to $230 but you can get it from racenation for $180 delivered. on ebay they are going for $130 but then non branded. if you want to know how they sound like on hondas just go to youtube and type in twin loop exhaust ! they are a go getteR! GOOD LUCK! N1's are too costy and arent worth it on a EK1 =D