i found a volant cai for $277 and i'm thinking about getting it. does it add the sweet sound that most intakes do? yeah i know that's a dumb question but i want the sound! haha. also, does it increase hp enough to feel any sort of difference and if it does by how much? i have an spi engine and i heard that i have to get an extra part for the intake to work. is this so? I appreciate any response.