ok im going to be putting a greddy sp2 or a apexi ws on my rsx type s. doe sany one know what one will make more power and how much hp diffrents is between them. i know the ws is a chambered muffler where the sp2 is straight through. ive heard the ws makes more powr tho, but if theres only a few hp diffrents between them im gona go with the ws because its alot cheaper