I hate to be the bearer of bad news but that catback is for a G37 Coupe, not sedan. The orientation of the mufflers give it away.

Your question is hard to answer, since your most likely the only person with those specific parts, we can't give you answer. You will have to experiment with exhaust parts which is time consuming and expensive. Sticking with your stock catback and replacing the resonators will surely be quieter than an aftermarket catback though. I'd suggest installing your purchased parts (headers, HFC), and then assessing the situation. If there is no drone and you want a little more volume, replace your stock resonators with a shorter free flowing resonator. Or, replace the stock mufflers with a straight-through muffler. Again, you're just rolling the dice.

That's why buying a pre-built catback from a name like Fast Intentions, ARK, Stillen, etc is appealing. There is no guess work on the sound or fitment.

 

Two things confuse me about the bad news...
1. The description of the item's fitment is 4 door sedan;
2. I thought coupe muffler is parallel to the bumper?

If this helps, here's the link to the eBay listing:

http://m.ebay.com/itm/OBX-Exhaust-Catback-For-2007-To-2013-Infiniti-G37-VQ37VHR-4-dr-Sedan-/182148737700?fits=Year%3A2013%7CMake%3AInfiniti%7CModel%3AG37&hash=item2a68e92aa4%3Ag%3AVg0AAOSwY0lXR3P2&_trkparms=pageci%253A7dca3611-b348-11e6-af3b-74dbd180a17e%257Cparentrq%253A9d0a80ce1580a2af577b157dfff0c178%257Ciid%253A1
Thank you in advance for sharing your knowledge.

Frank

 

I don't think so. The OBX Coupe mufflers are at an angle, sure, but it's completely different than the Sedan setup. This is the Coupe catback from their website (and everywhere else):



There are no Helmholtz resonators in the Sedan version, just a pair of dinky in-line resonators. And those cans don't look chambered... probably glasspack or turbo-style. I bet that's a seriously loud cat-back. I'm thinking Drone City.

Exhaust components typically fall into the category of, "You get what you pay for". So good luck with this.

 

The angle of the tips though is what has me questioning it. I could be wrong but take a look at ARK's design and compare it to this. But I agree with you about it being loud and droney. Not to mention it is a 2.5'' diameter piping.

I hope I am wrong Frank because I'm sure they will charge you a re-stocking fee if you wanted to return it. If it does fit the sedan, I think you will be the first member to own it. I've owned previous a OBX product that I've been happy with on my previous maxima.

 

That pic is off. Looks like they have the mid pipe flipped. That's why they have the mufflers oriented the way they do.
Flip the mid pipe and swap the cans and I think it might just work.

Definitely curious for a sound clip and your thoughts on fitment.

 

One has a mated x-pipe, and one has a connecting tube design. The in-line resonators are completely different, the bends are different, the hangers are in different locations. One has a mid-pipe support where the other doesn't, and one has a Helmholtz resonator at the cans.

Yeah, those are two completely different catbacks. And the Coupe version looks much more appealing, IMO.

 

Worst case scenario, you file a dispute with PayPal or your CC company if it doesn't fit properly. The title clearly states it's for the sedan.

 

I really appreciate having all this expertise freely shared. While a noob, I learn fast. To show my appreciation 2 clips of my other G (now my son's... it's hard to say "his" just yet) with Berk HFC's (I'm positive that's the brand I went with 5 years ago when I did it) and the Q300 catback. And some just taken pics of the unfinished x-pipe Invidia sent with the kit. My mechanic called and said, "Uh, it's ready, but there's a problem... they didn't finish welding a flange, and it's loud." I told him I didn't care and I'd drive it while Invidia was sending an X-pipe that had been welded on both ends, not tacked on on one end and welded on the other.

Cold Start of the '10 G
Some revving

The botched Q x-pipe:

 

Also, search Obx g37 exhaust on eBay. You will notice his model is listed for a coupe and another listing for sedan with the exact same pictures.

 

im confused guys, every hfc I look at says it only fits manual cars. Is this true? because I have a automatic and was hoping to purchase the ark r-spec hfc.

 

Sticker on one side of the box.


Same shipment box, different side. Tells a very different story; one that is obviously wrong.

I got the kit and the first sticker was the most obvious, and suggested they simply shipped the wrong system.

WRONG. The second sticker suggests it fits: 07 to 08 350Z; 09+ 370Z; 07+ G Sedan; and, 08+ G37 Coupe. This is impossible.

Those angled mufflers will not fit on my 13 G37xS. If they did, I would keep the system and have a shop modify the Y-pipe to fit around my transfer case. Even though it is within my right to return it for a full refund because they advertise it as fitting G sedans, not RWD only sedans. Mid pipes back should fit if that kit fits the 07+ G sedans, and there's no way.

It's not a case where they have the coupe kit and the sedan kit, and just have the wrong pics for the sedan kit (and simply accidentally sent the coupe kit). That second label proves it. The label is listing all the cars its contents purportedly fit; and, there's no catback system that will fit all those models.

I'm sending it back. They asked, "do you want the correct exhaust sent or just a refund?"

I said a refund. They don't know, it seems, they don't have the correct exhaust.

Now I understand why one guru told me my exhaust system would fit on my son's G, but my Nvidia Q300 catback wouldn't fit on mine without a mod (to get the pipes around the transfer case.)

My car is at the shop right now getting Megan headers and the Kinetix HFCs. I'll pick it up with the stock exhaust from the cats back... can't wait to hear it and see the performance pickup.

If I don't like the sound enough, I really don't want to settle for an axleback system. I like the 2.5" pipes on the OBX... nice, big airways... The tips are OK. But I'm not paying a shop to chop up the mufflers to make them fit, too. Get it around the transfer is one thing... chop up a coupe exhaust to fit my sedan, not in a million years.

Thanks for the help, men.

Frank

 

I knew it, those mufflers looked off. Sorry about all the wasted time Frank. I'd just try modifying the stock catback after you get the HFC/headers installed.

 

Men,

I now have the Megan headers and Kinetix HFCs on my '13 G37xS. This opened up the exhaust system back to the Y-pipe, where restriction starts, robbing those two mods of their potential (because it is stock system back.)

My goals/conditions of satisfaction going forward:

1. Low cost is a chosen parameter. I could buy an Invidia Q300 and have it modified to fit around the transfer case. That's a chunk of change; and, it would be convenient; but, that solution would rob me of the enjoyment of creating my own.

2. I want to use the defective Q300 X-pipe that came with the Q300 that is on my '10 G37 (Invidia, of course, sent a good X-pipe to my mechanics, and I got to keep the unfinished, "bad" X-pipe pictured below). I am looking for a shop that can properly finish welding the flange that's only tacked; then to make 2.5" mandrel bent custom pipes from the cats to the X-pipe.
Reposted these pics in case you didn't want to scroll up to see them....





3. I request votes on the best resonators and mufflers to have the shop weld up with 2.5" custom mandrel bent pipes... for the best sound.

4. And, votes on the best 2.5" stock for the pipes? On the Q300, it looks like fairly thick stainless.

Thank you for your kind attention. I look forward to being schooled by the wise among us.

Frank

 

I think what I wrote above would cost more than a couple of exhausts I've heard on here.

1. I like the sound of the Top Speed Pro-1 Y-back exhaust and the price. They're in back order until February. Does anyone have one for sale?

2. While I'm waiting I've been looking at and listening to the Manzo systems.

Frank

 

Sorry for the question if it noobishly annoys. Here's the justification... It's hard surfing here on a 5.5" screen... (frowns face)...

I want a Top Speed Pro 1 Y-back system for my '13 xS.

Thank you in advance for your participation in the accomplishment of this commitment.

Frank