Exhaust Opinions
 

So my current setup is:

AVO Turbo
AVO 2.5" Overpipe
t1r Catless 2.5" Overpipe
TRD Catback

I had my car up on jack stands last night and took a look at the TRD mid pipe. It looks to be as small as 2" around the resonator, which makes me realize that it wasn't really designed for an FI setup.

I'm looking for opinions about what I should do, and what some of the possible benefits are. Also, if there's another option out there that I'm missing, please let me know

Option 1)
Have a custom 2.5" resonated mid pipe made to replace the restrictive TRD pipe. This is obviously the least expensive, but I'm not sure if the TRD muffler will be a bottleneck.

Option 2)
New 2.5" Catback. I'm tossing around the idea of just replacing the entire TRD catback with the Corsa 2.5" catback. This will match the rest of my 2.5" exhaust in terms of sizing.

Option 3)
New 3" catback. Since my downpipe, overpipe, and front pipe are all 2.5", would I see any benefit to a 3" Catback? I'm considering the Tomei 80 or the Perrin 3" resonated. Also upgrading the dp/op/fp to 3" is not an option due to cost at this point.

My ultimate goal is about 280-300ish whp, so I'm not sure if 3" is necessary.

I would appreciate your opinions... thanks!

@midnight23 demonstrated dyno pull HP gains when going from 2.5 to 3 on same tune. Small, but still gains. He's in that HP range. I don't have the link off handed but its in the FI section.