Just had ppp fitted to my STi7 and have a couple of questions:

1) Everytime I lift my foot off the throttle I get this 'whooshing' noise a bit like air escaping. Is this normal as I never noticed it before the ppp was fitted.

2) Anybody who has had ppp fitted for some time could you comment on if the exhaust note changes much after you have done a few thousand miles.

Thanks

 

Could be that you are hearing the dump valve more because of higher boost.

Most exhausts change note over time (get a little quieter) as they get sooted from the ultra rich fuel mixtures Subarus (including PPPs) run.