How Good is the OEM Nismo Exhaust?
 

The Nismo 370Z comes stock with True dual exhaust already, that makes me wonder if switching to another dual aftermarket exhaust is worth it. Should I keep the Nismo configuration and change the Axleback only or just switch out the entire system?

How good is the Nismo-tuned exhaust that comes stock on the Nismo version? Anyone know the piping diameter of the exhaust?
Will I see any gains or is it worth to change the system to an aftermarket dual exhaust?

Iirc,

H pipe section is 2.1" and midpipes are 2.4"

That was for '09-'14 nismos, not sure if the '15+ nismos are different, but prob not.

Not good, adds +/- 4WHP, if you trust the accuracy of the dyno.

The Nismo S-Tune actually adds HP, conveniently, I have one for sale

The Nismo exhaust flows better but not much better than the stock Nissan 370Z OEM exhaust the difference is only 4-5 whp on a dyno. The sound and tone difference is minimal too. Replace your whole exhaust system if you have the extra coin to do it. From the headers back or the test pipes back. Aftermarket exhausts will flow much better depending on their configuration and design. Exhaust parts for the Nissan 370Z are expensive comparing to other vehicles.

Assuming you're saying without a tune...because with a tune, it's an 20hp gain, not 4. I only mention this as once I started modifying my car (which has basically the same exhaust) from OEM, the air/fuel ratios were ridiculously rich. Needed a tune to optimize the parts. I would suspect that it would be the same going from a stock non-Nismo exhaust to a Nismo.

An aftermarket CBE will net more power than the stock Nismo exhaust.

save money and go CBE, intakes and a tune. I would suggest leaving headers, HFC's/test pipes for when/if you plan to go forced induction. Otherwise, the costs far outweighs the minimal gains. Spend that money on upgrading brakes!

I remember reading that most of the extra horsepower (18 hp) in the Nismo comes from the exhaust system and a tune for it. So, it must be pretty good. Sound wise though, it is disappointing.

Yes it is a 2.5" HKS exhaust all you need is HFC.

I swapped in Fast Intentions resonated high flow cats and it improves the sound greatly with no drone. Quiet as a mouse cruising on the highway too. Get on it though and it screams.

I do agree you're better off buying certain aftermarket exhausts instead of trying to locate a used Nismo exhaust. But if you already have a Nismo, no point in swapping it out unless you go forced induction or with some crazy n/a mods and you'll need that extra 2hp at 7500rpm.

If you can find someone selling the h pipe and midpipe go for it! Stock nismo exhaust with stillen gen 3s and resonated Test pipes I made 310 to the wheel with an ecutek tune

Am I correct in reading this thread that there's an "H" pipe (joining the exhaust paths) under the heat shielding within the piping between the mid-pipe and cats on the nismo?

I was thinking of modding my OE sport exhaust to mimic the Nismo. Now wondering if it would be better to use an "X" in place of the "H" or no balance at all.

Old thread but wondering if there is a resolution to this question...Is the OEM Nismo exhaust a worthwhile upgrade for a non Nismo car? I am looking for a slightly louder exhaust than stock and more hp, but keep the stock header and cats to keep the smog people happy. My thoughts were drop ins (K & N), Nismo exhaust and a tune.

Also, I read that the Nismo muffler is heavier to quiet the exhaust more than the non Nismo muffler. Maybe a Nismo H pipe and mid pipe with non Nismo muffler is the answer? Thoughts?

It's pretty subjective. What do you consider slightly louder? The noise difference between Nismo and stock exhaust is not going to be very noticeable. May not be loud enough for some and may be perfect for others.

Your best bet is to find someone local with the same or similar setup so you can hear it in person. There are a lot of videos on youtube also.

Fast Intentions exhaust with no resonators is awesome if you keep the stock cats. Can't beat it. The only issue is the noise level. As stated above, your best beat is to find someone and take a ride to see if you like it.

HKS Hi Power is a nice quiet exhaust that performs better than the stock Nismo. And by the way, aftermarket tunes in California are being banned by the EPA so it won't pass smog.