I haven't read through this whole thread because, well it's 31 pages now, so this question was probably asked before.

What are the differences with X, Y, H and true dual pipes, and what are each best at doing? (N/A, SC, TT)

There are 3 possible combinations that you can have on the 370Z.

1. X pipe
2. H pipe
3. True Dual

We have built and tested all 3 variations and have found out what works best on the 370Z.

Here are the differences:

1. X pipe - Allows for greater scavenging between L&R banks at higher RPM. Larger interaction between the L & R banks compared to the H-pipe. Reduces sound and increases performance when properly designed and implemented. Most difficult and costly to produce out of the 3.

2. H-pipe - allows L&R interaction at low RPM but does little at high RPM to assist in scavenging. The H-pipe crossover just isn't large enough to flow all of the gases over during high RPM operation.

3. True dual - no interaction. Two straight pipes. Works well in some limited RPM ranges (aka race motors), generally not good for street applications. And sounds TERRIBLE on the 370Z!

For TT applications, just make your exhaust as large and free flowing as possible. There is zero interaction between the exhaust system and your exhaust port after the turbine wheel.

Has it officially released yet?

http://www.the370z.com/group-buys/66...tml#post149673

you better hurry up if ur interested....