I think four cyl. engines are inherantly raspy sounding due to the unbalanced nature of the engine. I'm not sure how much better inline 6's are. The more pistins the better I'd think. Many four's have balance shafts in them to make them run smoother. Seems like larger diameter pipes make more hp but increase the raspy sound. I wondered about putting a motorcycle muffler on a car once, one with tunable baffles, never did it but wondered. |