So I've scoured the forums for over a month (as well as the 350z ones) and have yet to find an answer for the my issue that is driving me crazy. This is my first post about my 2005 G35 coupe 5AT (still some issues to sort before I post pics), so the help is appreciated (I'll have lots of questions about valve body solenoids later, lol).

Current set-up is Berk HFC, Circuit Werks resonated y-pipe, Tanabe midpipe/muffler (OEM system had failed cats and rusted out the midpipe). Sounds great, nice and quiet in traffic, sounds great at WOT (except at lower RPM, where it's a bit too *bwaaaah* for me), but has a horrible drone from about 2.2k-3k RPM under load. Diameters from the HFC go 2.5-2.5 y-pipe, 3.0-2.75 midpipe, 2.75-2.75 muffler (the 3.0-2.75 only gives a slight hiss under load at lower RPMs, probably a bad gasket).

Now, I got the Tanabe because I heard it was quieter, more refined, and kept some original VQ sound from the factory. Most likely my Berks, but this isn't quite the case to me. Here comes the choice;

I already have FI RHFC on the way this month. I don't like being patient for things that annoy me, but for those with experience with exhaust, which is likely to give the least drone in that highway cruising range of RPM?

1. FI RHFC with my current Circuit Werks/Tanabe setup.
2. FI RHFC with a FULL Tanabe system (swap in a y-pipe to make diameters more equal).
3. FI RHFC with a Invidia Gemini.

I ask about the Invidia because (a) it's only a few hundred more expensive than a Tanabe y-pipe (why are those so expensive?) and I could offload the hardly used Tanabe for some cash-back, and (b) I have also heard that the Invidia is an even quieter system than Tanabe from some people. I imagine the closer to stock diameter (2.36 IIRC) would help in that regard. And before you ask, I've already tried ART pipes; the drone was even worse.

I had though Tanabe was a safe bet, but the drone gods have decided no. In conclusion; help!

 

Pretty sure it is the Tanabe because I had drone with it before I did the Art Pipes. The Circuit Werks resonated Y-pipe knocked the edge off but the solution is going to be to swap out the Tanabe muffler with a turbo muffler. Did that on my first Accord (resonator and Magnaflow), switched to a turbo muffler and drone was 100% gone.

I agree though that other than the drone (which is worst at 2500 rpm...70 mph in 6th) it sounds great.

I originally ordered the Megan exhaust because it was supposed to be the quietest but no one has any and its apparently out of production.

 

I looked into the Megan as well but yeah, can't find any anywhere. The Black series on a black coupe would be amazing.

I ended up getting the Tanabe Y-pipe, and definitely helped with the drone (the 3-inch diameter Circuit Werks resonator probably contributed to the drone heavily, even though it took the rasp away). Sounds gorgeous in the upper RPM, bit of rasp at heavy throttle when launching (probably the Berks; the FI RHFC should fix that problem). Highway drone is almost entirely gone as well, only noticeable/annoying at around 60mph, but who goes 60mph in VA? Then again, drone is totally subjective, so what's acceptable to me may be ear-splitting to the next guy.

I almost got the Invidia Gemini, but the straight through design made me reconsider. I like loud(er), but not ear-splitting loud, so I played it safe and kept the Tanabe muffler. Plus, unless I got a really good price for selling the Tanabe, Invidia was gonna be quite a bit pricier overall.

Now, to wait for those RHFC to arrive...

 

On mine, the Circuit Werks resonated Y-pipe took the edge off the drone that I had with both the stock and Beluga Racing Y-pipes. In the end though, I'll probably end up getting a turbo style muffler.

 

Update: Just got the FI RHFC on. Comboed with full catback Tanabe Medallion Touring, it's just amazing. Bit louder/deeper than stock at idle, growls a bit at low rpms, but stays respectable (a.k.a. no more "bwaaah" when accelerating). WOT is quieter than with the Berks, but I can actually hear the VQ warble now instead of pure noise. Will need to test more, but I think the backfire/crackle on de-acceleration is gone/reduced, which does make me a bit sad (only driven five minutes back to work though, so I'll see more later).

If you want a stock-sounding system with just a bit more volume, a bit deeper tone, and an amazing WOT sounds, I can't recommend the FI RHFC/Tanabe catback. It's not the exhaust for if you want to make a lot of noise, but it sounds mature and very VQ-ish.

I do have a rattle/grind when I first touch the gas, but I'll get under the car in a week or so to see if the mechanic forgot to tighten anything. Might just be the RHFC/gaskets breaking in.

 

The Tanabe does sound good at full throttle, that's for sure!

 

I have megan racing HR headers, Kinetix HFC, and Invidia Gemini catback. The sound is really awesome with minimal drone. I have no issues at really any RPM with crazy drone other than your standard exhaust growl so I highly recommend the Invidia.

 

Swapping the straight thru Tanabe muffler with a Dynomax Super Turbo muffler really knocked out a huge chunk of the drone, so much quieter at 2500 rpm on the freeway!

 

Makes sense, the Tanabe mid-resonator is pretty tiny. My car recently seems quieter with the drone, but it might be cause I've learned the bare minimum throttle needed to go up a hill, which keeps me just outside the drone range.

I'd hate to hack up the mid-pipe, but if it's that effective...what diameter muffler did you go with?

 

I just realized that you have a sedan, so different exhaust design. By the "straight through Tanabe muffler", do you mean the muffler on the end, or the mid-resonator? Cause my coupe rear-muffler is a different design than the sedan one.

 

I mean the actual muffler. That's what I replaced and it is definitely straight through. The shop initially thought I wanted to replace the resonator with the muffler and was telling me it might not fit and I'm like WTF, replace the muffler with a muffler. And yes the resonator is puny, but I'd have to order a longer one if I want even more noise control. But so much better now, definitely livable on the freeway now.

 

Huh, I'm out of luck then, with my coupe muffler (looks like the stock muffler but smaller). Wonder if I could weld the muffler you mentioned into my mid-pipe, cause it sounds like it's pretty effective.

 

Assuming you have a 3" exhaust (other sizes are available) this should work.

https://www.summitracing.com/parts/vpe-1142/overview/

 

Bringing this back from the dead. Shoutout to Scottwax for pointing me toward Vibrant Resonators; ordered an open-box Vibrant Resonator 1132 for $70, got it welded on for another $50 in place of the itty-bitty Tanabe resonator and BOOM, exhaust is perfect. The only drone to speak of is acceleration noise when hitting it from 2.6-3k, honestly almost stock. It is just enough to remind you that the car isn't bone-stock.

FI RHFC, Stillen intake, Z1 spacer, full Tanabe catback, and it's absolutely zero cruising drone, the interior is quiet but livens up when driving fast. It honestly reminds me of a current BMW with valves in the exhaust; it's perfectly docile cruising around (with more of an edge than pure stock), but screams when hitting it (pops and crackles when revving high) and purrs in the classic VQ way at low RPMs. My exhaust is now the definition of OEM+. Tiny bit louder, tiny bit bassier, basically just more exaggerated, but not obtrusive at all. Plus, I get all benefits of HFC and a catback!

Problem solved, 10/10 satisfied.

 

I ended up swapping the Tanabe resonator for the Vibrant as well. Got rid of the remaining drone and the boominess of the Tanabe. Plus the inside of the Tanabe resonator necks down to maybe 1.5" in diameter while the Vibrant is 3" all the way through.