it is loud but when you get to 4k rpm and above you feel like you are ragging it round a race track and just lovin it all the way to 7k rpm ! Performance improvement is sweet too, especialy from 6k to 7k in 3rd and low down torque in 2nd, 3rd, 4th and 5th. A worth wile mod. I do agree that if you do alot of motorway mile it does become hard work, round town it is lovely though, sounds more like a TVR.