Greddy Exhaust Drone
 

sI recently installed my Greddy Evolution GT exhaust. It's a beautiful exhaust; nice welds/flanges/etc...

I love how it sounds on startup/acceleration/downshifts. My problem is that there is insane drone between somewhere around 2800-3200 rpm.

Does anyone else have this exhaust with this problem? I still have factory cats

A few things to note:

1) Everyone says the fitment on this exhaust is great, but that's not my
experience. The Y-pipe seems almost just a tad too wide. I had to loosen the cats to get it to bolt up (I tightened the cats back down). I'm fairly sure that the Y-pipe isn't upside down.

2) Even though they are centered vertically and horizontally, my tips seem to stick out more than other pics I've seen with this exhaust.

The exhaust doesn't make contact with any other parts of the car

Is this an install error on my part? Can it be related to my small problem with the Y-pipe? I'm out of the country at the moment and don't have pics, so I'll have to wait on that.

A bonus question:
This particular exhaust doesn't have any flex pipe. Given that I had to loosen/tighten the cats to get things situated, should I worry about things being too rigid?

Drone isnt a result of a fitment issue, it's the nature of the pipes. You could attempt to use GTMat and CCF (closed cell foam) and insulate the trunk area.

Or pick up a pair of these...https://uploads.tapatalk-cdn.com/201...af0b18ea22.jpg

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I'm just glad to hear it's not an install error. Also, my drone is probably too strong for something that just pulls 3.9 stars

You could try the eardrum delete mod. I've heard it solves the drone issue quite nicely!

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Oh crap, I just ordered this exhaust yesterday. Now I’m worried.

It should get here next week and I’ll definitely let you know if there’s drone.

:rofl2:

You have to remember that the catback has multiple sections to it. Adjustments will always be expected when changing out from OEM. This doesnt mean that the fitment is bad.


My Gemini doesnt really have drone with normal driving, but when Im on the Highway doing 70 < mph, theres drone. Its not too bad, I got used to it.

I wouldn't be concerned about the fitment except in every post I've read seems like people have really emphasized how well it bolts up. Glad that I'm not alone though

It looks beautiful and sounds beautiful. I am interested in how well your Y-pipe bolts up. Also, what year do you have? For the longest time, this exhaust was listed to be compatible with 09-14, then very recently the later model years were included. Probably nothing, but I'm still curious.

An exhaust will also change over time too.

I installed a ton of sound deadening in my hatch (for the subwoofer, not exhaust) and a side effect was my exhaust is MUCH more quiet inside the car now.

The only thing separating the driver from the exhaust tips is the plastic bumper cover, the carpet, and literally a panel of sheet metal. If you bang on it, it'll sound like banging on an empty 60 gallon drum. I put a few layers of butyl mat back there, and 80mil closed cell foam. Cut down on road noise some too.

I'd be interested in more info about that...

On the bright side... at least this will keep my wife from wanting to drive it.

I have a ‘17.

I’m also curious and crossing my fingers that I don’t have major issues. If it’s a little drone, I can live with that, otherwise, I’ll have the shop put in some resonators, if possible!

Ok, I have a '17 as well. Please don't forget to report back ok this. Other than the y-pipe fitment is great. The tips are very easy to center in the cutouts, but mine do stick out s little far

Quick synopsis: GTmat is less expensive Dynamat, no reduction in quality. These mats primarily reduce vibration coming through the metal body of the Z. CCF you can get on Amazon, it's just non-absorbent foam. Comes in rolls. This absorbs sound.

I did the entire trunk area, bottom and sides, shock towers, brace between the towers, and front/back of both rear wheel wells with GTmat and CCF. Two layers of CCF on the wheel wells. Put CCF all along the area behind the seats and under the OEM bar. Strategically placed GTmat and a full layer of CCF on the rear portion of the front fender liners and on the body of the car behind the front fenders.

CCF is what deadens sound so you want to absolutely go to town w that stuff.

I noticed a very significant reduction in road noise - can barely hear a pebble in the wheel wells. I'm quite pleased with the effort.

It's a PITA to do bc everything has to be cut to fit perfectly, no gaps. I highly, highly recommend you put the Z on jacks or a lift if you have one - spending 7-8 hours bending into the trunk space will cripple your back. Also helps to pull the seats out so you have room to work in there. Be gentle on the plastics and pull the FSM to see the pattern of removal.

Hope that helps.

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This all over the inside of the hatch, directly on the metal. A few extra layers above the exhaust where the car is thinnest until all I got when knocking on it were solid thuds:
https://www.amazon.com/gp/product/B00URUIKAK/

Then this on top. It's thick enough that you have to cut it strategically or everything won't go back together. This is what actually blocks sound.
https://www.amazon.com/gp/product/B07784JJ1S/

My entire hatch, wheel wells, and behind the seats are covered. I also did my doors because I hate myself.

That's a masochistic level of self-hate.

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Drone
 

I installed a heap of sound deadening in my trunk and it definitely made a difference but I still got that ear piercing sound at around 3k rpm. The biggest difference came when I removed the rear vent pieces and covered the holes with sound deadener. Made the car so much more enjoyable.

I just turn the radio up to get rid of the drone.

Which vent pieces are these?

Yeah I sent my radio into security protection mode the last time I pulled my battery to install my gauges. I never got around to looking into it because I never really even used the radio when I was in the Z. But thats a story for another thread.

Unless someone knows how to fix it... (Hijacking my own thread)

If you pull the trunk plastics you will see two louvered vents, one on each side of the rear. They allow air to escape the car when you have a window open and for that reason I wouldnt seal them.

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A few other things to check...did you remove the tin heat shield that was above the stock muffler? It vibrates a lot ...also the hatch release motor gears rattle very loud. You need to open it up and apply some heaver grease over them and that will stop...also I had some rattle coming from passenger rear tail light ..I removed it and used some weatherstripping under the section where it bolts to the body. These won’t fix actual “drone” but I noticed with my short tails around 3800 rpm drone/rattle was awful and these things improved 80% of it.

Could you guys post some sound clips with the exhaust? I’m looking to eventually get one but really would like to hear more sound clips then the few online.


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Yeah, I'm going to pick up a suction mount to put the gopro on the rear bumper. I'll try to get some in/out audio this weekend.

I'm more of an in/out video type of guy but different strokes for different folks I guess...

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That too lol

Anyone happen to get some recent sound clips with the greddy? I was literally minutes from placing an order and a friend told me it doesn’t sound good which second guessed my decision.

Anyone running it with ART pipes?


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I took some video driving around with the GoPro suction cupped over the exhaust but haven't gotten around to YouTubeing it yet. I love how it sounds. Even given the in cabin drone I would not change it. Even still being NA without a tune I get decent exhaust burble, which surprised me. I need to edit the video because it's too long, but I will try to do that tomorrow. I will also take one that will show the heavy drone between about 2.75-3.25 rpm.

Overall, I'm more than happy with it.

I have to go to a DIY mechanic shop because I can't work on my car in my apartment. It's full of people who "only buy 'merican". They roll their eyes whenever I bring my Nissan in. On the first start after installing they had nothing but compliments. One even went so far as to say it sounds like a V8.

I'm still on stock cats

There is a discontinued version with a very similar name that sounds like **** IMO. I wonder if that's what your friend was talking about.

Discontinued: Evolution Evo3
Mine: Evolution GT

Yup! I did the same, the entire back half of the car is a tin can (likely the last nissan product I'll own).

Was well worth adding sound deadening. I went with gt mat + nioco + some foam layering. Night/day difference, then again, I have the 18" resonators on the FI CB setup.

Were you able to upload that video?

Can someone tell me the hardware that comes with the evoGt, please? I bought used ART pipes without hardware and need to figure out what else to buy to install everything


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Sorry man, I'll try to get it up today or tomorrow... Been busy with work
The evolution GT came with:
Y-pipe
X/crossover pipe
2 resonated pipes from the crossover to dual mufflers. Tips are not removable
5 gaskets
All necessary nuts and bolts
License plate frame
2 Greddy stickers good for +5whp each

No worries and thank you for the parts list!


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So I installed the Evo GT last Sunday and also put on ART pipes. I can confirm, there is some serious drone. I need to check what rpms they are at again, but i think its about 2750-3200 there is really bad drone. When I don’t feel like having my head explode, i drive the car only shifting between like 2000-2600 rpm.

This exhaust is LOUD!


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Yeah, that's the same rpm range for me, and I have stock cats.

I've had it for a year and a half now w/ Motordyne ART pipes and love it, but I do have the same drone you're talking about. Doesn't really bother me as it's not my DD, but I could see how it could get old if it were.

Exact setup, Greddy Evolution w/ ART pipes

https://www.instagram.com/p/BsD1xyng...d=yszkbqhocdwp

https://www.instagram.com/p/Bw17G15l...=10lx0i1vf397s

I see you on the dyno. Do you have to have before/after with just the exhaust?

Yeah, I love the exhaust. I'm mostly used to the drone now, but it does have the side effect keeping my wife from asking to drive it.