I know this isnt totally related to Hondas, but why does when a VTEC kick in, the exhaust note changes? On the same topic, why is the sound of a Italian V-8 (360 Modena) sound so godly and an American V-8 (GTO) sound so deep (aka Badass)? This might seem like a dumb question to some, but I'd like to know for myself. Thanks

 

The exhaust note changes when VTEC kicks in due to the change in cam profile.

Most Italian car manufacturers use extremely well balanced "flat-plane" V8's (which use 180 degree offset rod journals) while most American car manufacturers use the more traditional 120 degree V8's. Flat-plane V8's fire like two 4 cylinder motors running in tandem with each other resulting in a nice engine purr, while a 120 degree V8 fires a bit more unusually, thus causing the "rumble." A lot also has to be said for the different motors' specific internal dimensions and the effect that they play, but it primarily has to do with the fact that the Italians use the 180 degree motors and the Americans use the 120 degree motors.

You could turn a small block 350 into a flat-plane motor by making a suitable crank and cam, and then messing with the firing order, but it really kind of defeats the purpose of having a small block 350.