Stillen or Nismo

Spartan 1771

The diagram posted is of the stock Z exhaust (in yellow) and the NISMO exhaust that comes factory installed from the dealership (in red).

According to Nissan, it is responsible for 50% of the 18 horsepower difference between the basic Z and the NISMO. This is a completely different exhaust then the NISMO S-Tune, that is available as an after-market add-on from the dealership, or from your local performance shop. The NISMO exhaust in the diagram (factory installed) is actually better designed then the S-Tune, because it is a true dual exhaust. Although this diagram shows a y-pipe configuration towards the front, this is just from an outward appearance. There is heat shielding on the outside, which gives the outward appearance of a single pipe, but in fact there are two separate pipes underneath.

The issue with the S-tune is that it still has a true y-pipe configuration that comes together in to one pipe, and then eventually branches out in to two again, just like the stock Z exhaust. Although the muffler on both exhausts (NISMO & S-Tune) appears to be a single unit on the outside, it has two internal chambers that are completely separate.

From what I understand, the factory installed NISMO exhaust is good for a nine horsepower gain. Because of the different configuration, the after-market S-Tune will add less of a gain.

If I were going to go with a NISMO exhaust, I would suggest you find someone on here selling their slightly used NISMO exhaust off of their NISMO Z, rather then buy the S-Tune. you will spend a lot less and gain more HP.

Just my $0.02 worth.

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~Rob

-DD Air Guide, Stillen G3 CAIs, 63mm Throttle Bodies, Motordyne M370, Berk HFCs, FI TDX CBE (non-res, CF), Sprint booster v3, Ecutek Dyno Tuned, and the list goes on...