i have the hks td. its 60mm=2.36". if i were you, i'd go to the aps site and look at the exhausts they have developed for their/your system. you might want more power later, in which case their 3" would be beneficial.

 

So what you guys think about those videos of the exhaust system

 

What do YOU think about them? That's all that matters. Just about all exhausts out for the Z right now are designed for N/A, so they're all going to perform about the same with forced induction. The only exhaust out right now that is meant for F/I is the APS 2.5" TD, and the SFR/HKS 3" true dual, like I have. GReddy is supposed to be coming out with an F/I version of the Evo2, but who knows when we'll actually see that.

 

+1
just get the aps or sfr, and be done with it.

 

Just changed my Nismo for the APS, much better suited to TT. Lovely exhaust, best quality system I have ever seen. Fitted like a dream.
Boost is up 1psi over the Nismo, so flow is much better. Feels much quicker with less lag now. Time for a retune.