ANMVQ

iTrader: (13)

ARK uses a Xpipe also? The whole X pipe or H pipe thing always interested me. One says to make more lower end( H) and one says makes more up top (X).

An looking at this system compared to mine it looks like it WILL not fit a X car.

Rochester

iTrader: (9)

The picture from my post is the current FI setup.

That's the ARK Grip in your photo... flex sections, x-pipe, side-by-side resonators. According to their website (), the ARK Grip is marketed to both RWD and AWD Sedans. AFAIK, it's the ARK resonated cats that have model restrictions, only supported by the 6MT.

And I agree with your confusion. Based on minutes of research (LOL), there doesn't seem to be a consensus on which is preferable, just a general disclaimer from everyone that "every car is different", and that on modern cars you should have an overlap between exhaust banks, of either type... X or H.

lobuzz311

iTrader: (6)

So the videos of the coupe version of any exhaust don't seem to be very relevant to the sedan. The Top Speed axle-back on the coupe is louder and throatier than the sedan y-pipe-back. (or at least it seems that way)
It must be the way that it is piped just makes it sound much different.

ColumbiaSkinny

Fast Intentions description of their sedan exhaust....

ANMVQ

iTrader: (13)

The difference between the sedan coupe exhaust (Ex the muffer) is the the resonators size the coupes are small hence more exhaust tone. Id rather have the same tone on the sedan , but maybe they think the sedan should be more luxury

ZahyMatar

iTrader: (4)

So has anyone ordered this exhaust yet?

socketz67

Exactly, resonators really only exist in the exhaust path to 'tune' the sound, nothing more. However, it does not end there.

The exhaust diameter on the sedan is visibly smaller (look at the taper on the sedan midpipe compared to the coupe) as it exits the resonators. This was probably done to reduce noise in the cabin.

Add the standard stock noise and absorption focused mufflers (which are also very heavy for this reason): Understanding Muffler Design and Sound Absorption Strategies - Street Legal TV

Then ask yourself, where were the tradeoffs made?

I cannot find a pic of the Q50 midpipe. I wonder if the same one is used that is leveraged on the 2007-2013 sedan?

Also. If you are interested in Y-Pipe vs. X-Pipe vs true dual discussion, there are some great threads in the LS1 forums. For the most part, these guys (i.e. larger cubic inch motors) pretty much agree that very little if anything is gained from a true dual setup and that manufactures use Y-Pipes for a reason (not because they are cheaper to make).

G37 Coupe Midpipe:


G37 Sedan Midpipe:

Rochester

iTrader: (9)

That's a heck of an observation, how the Sedan pipes taper to a more narrow diameter.

And the resonators... sure does look like the Coupe resonators are shorter.

For some added perspective, here's my old OEM catback sitting on the floor after removal:

socketz67

I'm now curious to know if the cats and the Y-Pipe diameters are different on the Coupe/Z and Sedan. There are several which reported that the coupe uses larger diameter cats and that there is a different PN for the Coupe cat. What adds to the mystery is that the coupe is only rated a couple of HP higher than the sedan, which if true, negates any argument regarding larger diameter piping adding HP. Interesting.

socketz67

Funny what a few pics reveal isn't it.

We used to share more pics of these types of things on the G35 forums, which is why I think there is more experiementing with OEM mods on the 1st gen. It also helped that the G Sedan, Coupe and Zs shared alot of parts without much customization needed.

HEUGE

Not my video, but I dearly miss the tone of my 350Z with the Weldina Nismo exhaust. No such product for our sedans, right?

socketz67

Is it just me, or does that sound alot like the coupe? Hard to compare this to the sedan since the Z and coupe use the traverse/single muffler design. Bimmers also use these. I think they have a bit more of a distinctive sound.

I think these Flowmasters sound pretty close:
Also, if you look at the stock muffler, the inlet pipe appears to be alot smaller than the outlet.

I wish I had a tool/method to measure everything and confirm.

socketz67

For comparison, here is the Top Speed midpipe:



Resonators look smaller (maybe? not as small as the stock coupe though), and the tubing is 60mm, which is 2.35 inch diameter vs. 50mm stock (we know this because the Tannabe axleback bolts right up to the stock mid and it advertises 50mm).

socketz67

Thought this custom system would be a go add to the thread.

Interesting how the center inlet muffler (stock is offset inboard) requires those 90 degree bends, which I believe would defeat the purpose as the OEM system has a more optimal tubing design after the midpipe.

ANMVQ

iTrader: (13)

Funny how I never looked at the pipe diamater of the 2, and I have swapped systems , I took my couple exhaust and installed it on my sedan and the only change that was needed was at the mufflers, My thread here

https://www.myg37.com/forums/g37-sed...-to-sedan.html