SPD tuning advise vs. what everyone else says including COBB
I'm looking into exhaust systems, and after reading almost everything on the web I thought I had picked out just what I wanted...and then I read the Cobb tuning website. Every other tuning shop recommends 3" pipe while Cobb says that its totally not necessary and the 2.5" stock size is fine unless your looking for 500hp, they also say that 3" pipe will actually cause the turbo to have longer lag. Also, other shops say the stock engine can safely handle 350hp at least, while cobb claims anything over 280hp will require replacing the turbo and other internal engine parts.
My performance plans for my WRX:
APS turbo-back and up-pipe
replace turbo inlet hose and intercooler hoses
I think this will leave me right around 300hp...Should I go with smaller pipe for the exhaust? Also, will I need to change my turbo (which then means I need to change my intercooler) or any other engine parts so I dont run into problems? Thanks for all the help...sorry the post is so long