I think the P&L and the AMR would be the best power makers as they are an absolute 3" all the way through unlike others that taper down to 2.5" at the Y-pipe. Or you could do the Invidia N1 which has been known to make some good power.
Your right 2.5" would be just fine but some of the exhaust makers are going towards the old "it's a true three inches all the way to the tailpipe" marketing campaign.
Here is something I found cool. Idk if this exhaust will be available to the public but it is made by a company called type-25. They basically do what Cosworth did in England and built a beefed up DD track ready STi. This is their exhaust for the '11 sedan. Like I said idk if it is available so I won't put it in the list, but it sure looks pretty.
As the title said, I now have IHI VF56 turbo from WRX STI R205, which means equal length manifold.
And I will get to the point; it does not drone. Not in this setup.
Straight forward conversion; no fuss
Parts installed:
1. IHI VF56 turbo from WRX STI R205
2. OEM twin scroll exhaust...
I am wondering if this is a direct bolt on just as if is stock. Will it cause any back pressure problems being that the 09 wrx is single pipe whereas the sti is quad tip?
In a bit of a rush due to inspections and seeing if this is a viable option.
I have to get my 2011 STI smogged again (first time was two years ago). It's running a stage 2 protune with Invidia turboback catted exhaust and an AEM cold air intake and no other engine mods. 3 years ago the secondary air valves failed, so i installed plates to block the system and then had...
Due to popular demand from others looking for a more tame exhaust, I wrote a review with videos of the Milltek catback for the Subaru Impreza GR generation STi hatchback.
I had read a lot of the reviews on the Corsa exhaust and bought one trying to find a catback with more flow than stock, but...
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dlheman · updated 
Bumblebeelotus · updated 
