I own a 2008 wrx sedan and wanted to know what gasket's/parts I need prior to the installation of the down pipe. I plan on purchasing an invidia down pipe (link below) and bumping up to the stage 2 torqued performance map (currently TP stage 1 and love it). I should have all the tools needed, I just need to know what you guy's recommend buying that will not come with the down pipe that ARE needed for a proper install (such as gaskets, etc.). I read a couple reviews that stated I need a "3 to 2.5" adapter for a good seal." I am assuming I buy these from grimspeed? I'm clueless as to what I actually need. Also, is this a good down pipe? Anything I should beware of?
Invidia Downpipe Divorced Wastegate Subaru Models (inc. 2008-2014 WRX / STI) HS08SW1DPN at RallySportDirect.com (Down pipe wanting to purchase)
GrimmSpeed (Possible gasket needed? Turbo-downpipe)
However, I am not sure exactly what I need.. (such as the 3-2.5" adapter). If anyone could point me in the right direction or link me to what I need, I would greatly appreciate it.