power roars are claimed to help draw in cooler air by replacing the standard plastic intake with a metal version and this is turn creating a apparent small induction. The claims it makes of bhp and induction is utter tosh, it does nothing but look good, you can make one your self for more than half the cost.
if you change your filter for a sports one will change the noise, your exhaust system will change the noise, if you drill holes into the filterbox this will give an induction noise as more air is forced through a larger area, not to everyones taste. you change a filter every 50,000 miles on normal conditions aint that much of a hassle. british weather dont bring shed loads of dust into the filters.
