After talking to a Subie specialist he recommended a cobb access port with some additional tuning, a catted downpipe and sti muffler.I want performance without attracting attention.Is the sti muffler freer flowing?poss.3"pipe?? will I notice a difference with or without cat?Can additional tuning be done with an accessport?This probably has been covered before but could not find..
There's a small difference between catted and non-catted. I personally prefer the catted since it pollutes less and gladly give up the 5-10hp potential gains to protect the environment a bit. The STi muffler flows better. If you're worried about noise you can always get something like a Borla Hush or Prodrive too. The AccessPort out of the box does not give you anything except the ability to load pre-made maps. Those maps work well, but are conservative and won't give you the ultimate potential. You can however go to a good tuner and get a ProTune which will give you a map specifically tuned for your car. Or you can get StreetTuner if you want to DIY, but I would recommend EGT and wideband gauges at the very least for that. Also, the OpenECU tools have come a long way and are worthy of consideration for a MUCH cheaper way to tune. They do require some more work and aren't as cleanly plug-n-play as the AccessPort (yet).
If I get the access port and then later want more power do I start over again (In other words do they use it for protune or??)I prefer conservative even though 'ultimate potential' sounds much cooler.Thanks..I probably would go with the borla like their sound and quality .just do not like their price..
There are plenty of used turbo back exhausts on all of the forums. Find something that is decent that someone is selling, and I guarantee you will get it at least 25% less than what the retail price is. If you protune and add something to your car engine performance wise, its a good idea to get tuned again. Luckily, Cobb makes preprogrammed maps as moose said that cover a combination of different mods. Definitely do some more research before you start dropping the $. There is always something cheapier or better if you spend the time on the internet.
I went with Ecutek for my 06. You can see everything else I've done here: http://www.wrxatlanta.com/forums/showthread.php?t=6380 I'm estimating 250 WHP 320 W/ft.lbs.... but that might be a tad over what it actually does.