hi-flo cats will yield you more sound and more power.
Did you do a ECU reset after you installed the Z-tube? Maybe you can get a little more bark out of it if you do.

Good luck

 

ok, well i installed the Z-tube and K&N filter on my 05 6MT and yeah, really no difference at all in sound. if it gives me better gas mileage then i'd say it was good to do.....but as of right now......worthless mod as far as sound. i just don't get how this would be so different if you have an 03 or 04 (good gain in sound) compared to the 05 or 06, which provides pretty much no change at all????

 

As many have said before, the lower manifold that feeds the cylinders is different on the 05+ 6mt's than the models before it. I can't tell you why this causes different mods to behave differently but it obviously does. Bottom line, your motor has different hardware than mine.

 

I have an 04 6MT and theres no sound difference in the mod...

However, after having the ztube\kn filter, I have noticed better gas mileage.. not a total waste of money on the mod, probably benefit other mods in the future but as for just having the z-tube don't expect no sound or performance.

 

Little late to the party here. 2003 sedan Auto. I recently put in a Z tube and a new Nissan panel filter & removed power duct. Nice sound but that's all I noticed. I came across a great deal on a new K&N panel ($30 local guy selling one from a Maxima) and dropped it in. To my suprise, I can actually feel an ever so slight difference. Mainly in the lower end. IMHO, when I've done the K&N panel on my old maxima, it would make a slight difference when it was really new or newly cleaned. So we will so how it feels in a month or so. I'll track the mileage on the navi also.

 

The Z-tube and removed Power Duct made my G35 have quite a bit deeper induction growl. Under load and about 30-50% throttle, it sounds very much like having an exhaust. After adding my MD spacer last weekend, the induction noise is even louder. It's almost frantic.

Like Jeff, I noticed an "increase" in response after adding the Z-pipe and removing the duct; however, I think the noise is fooling my butt dyno.

The idea that the Rev-up motor doesn't gain the same kind of growl from the Z-pipe that the non-Rev-up motors gain makes complete sense to me. Due to the shorter intake runners on the Rev-up motor, the induction noise will be lessen. My 96 Maxima's OEM intake manifold had really long runners and the induction noise was almost deafening with an intake. I then added a JDM intake manifold that had a variable intake tract that increased high rpm power dramatically at the expense of some low end power. As a result, the induction noise below 5500rpms was not near as loud as it was with the OEM manifold.

 

i just performed this mod today.
revving at idle i didnt really notice anything different
on the road, i still didnt notice anything...i could rev all the way out and it would sound almost the same
but then i went WOT, which was normal...until 4k rpm. then the engine took on an entirely different tone. like it was angry or something....
i couldnt believe this little mod did that....

btw i didnt really notice any difference in speed, for the better or worse, but then again i havent been driving my car much in the last month. it does go to show how big of a difference the sound is though; if you pay attention to that sort of thing you'll instantly notice a big difference (its obvious imo)

 

again.....looks like you can see differences only if you do not have an 05 or 06 6MT...........