I'm going to be getting a y pipe soon an was reading that a 2.5 to a 3' will actually casue less flow. I have the stock cat back and will not be changing it.. Cat back cost to much $$$..

 

Um which Y? And which dia pipes are you refering to? The individual downpipe dia or the collector dia to the catback. I don't think your oem catback dia is 3"

Your PM was way too confusing so I didn't reply

 

changing the Y pipe only on a v36 does not do anything. save your pennies for something else. If you just want sound then just swap the mufflers only.

 

I have a G37 and the Y pipe I'm looking at was the Ichibna, But pretty much a lot of them say 2.5-3'.. The 3' is the collector I think?

 

2.5 In
3.0 Out

 

Yes correct, Is that not good? Shouldnt it be 2.5-2.5?? Trying to move air from a 3" collector to the stock pipe will cause issues no?

Product Description:

100% T-304 Stainless steel with polish finished
2.5" Inlet & 3" Outlet, Fits All Catback Exhaust
Tuned for all-out performance for Racing applications only
NOT C.A.R.B. exempt
CAD-rendered design eases installation
CNC Machined Flanges with Mandrel bent tubing
High Performance Y-Pipe Increase Around 8-12 HP & Torque
Direct bolt-on with all installation accessories
Each product comes with one year warranty

 

if anything best ypipe for our car will be the HR Y pipe from the Z.

size diameters are just slightly larger than our Y pipe oem. I wanted to test this awhile back but I sold my HR ypipe.


2.5 to 3.0 is not worth it.. it's then connecting to a 2.25 pipe

 

I have a 2010 G37 dont I have a HR Y pipe on the car now?? I thought the 3.7 Was A HR motor?

 

lol he already has the HR pipe

 

noticed I said Z

350Z HR ypipe is different from 07-10 Sedan HR Y pipe.

 

Ok so even if the aftermarket Y pipe fits both cars the Z pipe (Stock) Is a little bigger?
Just confused casue the power output on both cars is the same?

 

IMHO the minor differences aren't really worth it. Isn't the most effective exhaust something with a 3" outlet + 3" catback? Either do it all or not it all?

 

power is just a rating

for some reason the 07-08 350Z hr ypipe diameter is larger than of our Y pipe. the piping design is similar but the HR pipe larger diameter has better flow.

Now can I prove that no.. But with the piping having such minor larger diameter, it will help with the flow of the exhaust.


there was a big thread here with pics of HR ypipes and diameter sizes.

In all, just add an exhaust system that is cat back, not Ypipe back. Or just add mufflers.

 

3" is great for FI but I thought our cars reacted better with 2.5 piping?

 

dont do it .. youll have rasp ..

i have a stock Y into a 3" midpipe ..