Currently I have the following power mods:
-Mishimoto Post MAF Tubes paired with aFe Filters
-FI RHFC
-Motordyne Resonated Y Pipe
-Top Speed Y-Back

I've been looking into upgrading my intake to SOHO 69mm or Mike Upton 3" intake. I was also looking into replacing my top speed exhaust with the thaitaniumperformance 3" dual exhaust.

If i had to choose between upgrading the exhaust or intake, i would think the intake woud yield better results, since catbacks are mostly for sound and not power. Although, I'm not sure if a 3" DUAL exhaust is any better than a 2.5" dual, in terms of power.

Chime in and let me know your thoughts.

My dyno tune is July 18th with admin tuning, so I still have some time to swap things around.

 

I was told you can add exhaust after the tune but not intakes. Intakes are a must before tuning or your wasting money even tuning at all.
3in exhaust is a better option ove 2.5 in

 

I agree with going with Intakes and then tuning them. I've had Upton's kit and for the price, its hard to beat considering the prices of other 3" intakes.

I've had the same exhaust setup as you, Motordyne y pipe and Top Speed exhaust, then switched to a full Motordyne system, 3" after the y merge, and part took in a group dyno day. different days but same dyno and i didn't see any gains that couldn't be ruled out for weather/temperature variables. I didn't have the dyno sheet to over lay with my previous to check mid-range changes, but peak number wise, there was essentially none.