The basic rule of thumb is short, open drag pipes allow higher horsepower very quickly, but tuned exhaust pulses from longer baffled systems allow for greater torque.
Exhaust noise, as we all remember from our yoof, does not equate to power or speed. It just makes you smile, although 99% of people think you're just a knob. That's what Monica Dribblethwaite told me outside the chip shop.
I don't want Honda-like exhaust noises, but equally I don't want obnoxious. My neighbours certainly don't!!
