all i got to say is WOW. . .low rumble at idle. . sound tapers off at WOT . . i just got to love it. . I've been in cars with loud exhausts and couldn't stand the drone in the cabin. . this doesn't drone at all . . very quiet. . it just sounds like the boxer engine just a little more amplified. From the caculations on my super accurite buttdyno . . i say an increase in about 7 hp . . give or take a couple horses. . .once i get my downpipe and uppipe in. . i'll be set for another couple of months . . .thanks rallispec!!