;-)

sorry OP, back on topic

It is true you dont need a 3 inch to make 550whp on these cars, it has been proven with plenty of turbo cars out there. But now that there is a 3 inch exhaust available it just makes more sense to jump straight to it.

Thanks everyone for all the information.... Looks like, although not absolutely needed, it might make sense to go ahead and purchase the 3" exhaust now if I have my mind set on big power gains later down the road.... Anyone have any suggestions on good 3" exhaust systems? I looked at the greddy T IC exhaust system, but wasn't all too thrilled with the sound. Anything else out there worth looking at? Also, based on my research, I looks like I'll be opting for a GTM twin turbo kit, so any exhaust I get would need to be compatible with that. Thanks again for all of the help.... It's very much appreciated!

Get the Fast Intentions 3 inch exhaust it's the same one I have on my car. I use to have the Greddy TIC and now have the F.I exhaust, the link to my thread has dyno video's of both, on page 4 it's the F.I exhaust.

http://www.the370z.com/forced-induct...otor-tt-4.html


http://www.the370z.com/intake-exhaus...aust-here.html

That would be a great option! I love the look and quality of the fast intentions systems. Would this be compatible with my current NA stock setup? Also, would I need to get any tuning done after install since the 3" system is a lot more open with less backpressure?

Please share who has done it and let them know to add to this thread: http://www.the370z.com/forced-induct...ed-builds.html
Really trying to get a solid book of builds together from everything, so far I only have 1 build that made almost 550whp on a 2.5" exhaust and I really do not have much info from the guy other than he cranked the boost up above 10PSI to do it.

The car made 550whp even, and please note that the actual boost pressure at max HP is about 9psi (10psi at 6,000rpm and falling). The reason the boost is up in the early rpms was due to having a manual boost controller. Because it is a manual boost controller, there was no way to controll boost in the upper rpm's (like haveing an EBC and the option to increase the duty cycle). So it was turned up so that we can be as close to 10psi as possible at max power. As a result the boost was up to 12psi at 4500rpm.

http://i18.photobucket.com/albums/b1...scan0001-1.jpg



The reason I say the 2.5" dual will make a lot of power is because of that graph. There is no sighn of it tapering off. It is just a nice linear line, with no dips, and no falling off at the top.

This is a Boosted Performance single, twin scroll turbo with a Precision 6266 billet T4 1.0 a/r. 3" down pipe to a Y-pipe going to the F.I dual 2.5" exhaust system with 14" resonators.

Here is a GTM TT Stage 1 with the 2.5 Fast Intentions it was my friend's car the engine has sence blown up. The care did make 550Whp without a problem, as far as other gas cars there there are countless GTM threads with cars with 2.5 inch exhaust making power.

[IMG]http://imageshack.us/a/img202/392/nismo481212psi1.jpg

Not trying to derail the thread, but for informational purposes - what caused the motor to fail?

Mr. Squeeze..... Can I use the fast intentions 3" exhaust on my current NA setup? Or is this only for cars with the turbos? I will eventually be going to FI but would like to change the exhaust prior and would rather not have to do it twice

I personally wouldn't run the 3" exhaust on a non-turbo car. It's just too big for use with a NA car. I would expect a very noticable loss in torque with a 3" exhaust on a NA car. Buy a used cat-back for a couple hundred bucks from another member here for now, and put the 3" system on when you get the rest of the kit together. Then turn around and sell the used cat-back. I doubt you'll lose more than $200 if you shop around.

gotcha . . . thanks!

How would you lose torque by lowering the back pressure on the exhaust side? If anything your gains between a 2.5" and 3" would be minimal since the 2.5" has been proven to be sufficient all the way up to 500 rwhp. Its all about flow, and only flow, make it flow better and you have less back pressure. Less back pressure less work the engine has to use to move the exhaust out of its cylinders and thus make more useful power.

:icon17: Oh crap. The eternal backpressure debate.

The car was drivin very hard for 13000 miles raced all the time. A rod shot through the side of the block.


You can use it you will lose a little low end tq, but if your going turbo down the line ,and dont mind that then get it.