the ferrari's scream, rather than hum or gurdle.

pmsl @ trying to describe what an engine sounds like though I remember reading in Fast ford years ago:

A bailey dumpvalve goes "ptsssh"
A whistling dumpvalve goes "twweeesshh"
And no dumpvalve goes "ptllleeeee"


I think the exhaust has a big part to play aswell though, i.e straight through, manifold header lengths etc.
IMO that scooby sounds cack, the bogo scooby of billy no mates down the road, with just a big mumma exhaust (hks?) and filter sounds mucho better (but thats just me )