cico

Sorry already posted on "Drivetrain" but got no answer there !
Thanks :

Hi mates,
it's been a while since my last post but now i'm back with a new question for you.
I'd like to fit my '98 -full decat+filter- with a modified wastegate and a new pop-off valve...
what do you think of these mods will they really make my scoob gain power and will they damage the reliability of the car?
Do you have any site address regarding this issue?
thanks guys
Cico