you my frind are so right I own one the RELICS the 160 slipp-up of BMW that were packaged as 540i but are M5 and they do get loud. According to my mechanic the reason is due to the alteration that they had to do in the engine so that it would be similar to the 535 they couldnt perfect the engine noise supression in less than 5 months. This cars are here by a miracle