Invidia Germini catback

[RZ34>Mk.V]

Hi All,

Thanks for sharing this post, I have installed the Gemini Catback Exhaust on my 2023 Z.

I was wondering you have experienced the following, maybe I have done somthing incorrectly please advise.

I have AMS Full Race Downpipes (just in case this matters).

I expereinced the following:

1) A drone & rattle inside the cabin with vibrations felt in doors and seats inlcuding the steering wheel when driving in the 2000-2500rpm range.

2) Is the Exhaust designed to be the lowest part of the car? I find it makes contact with the gound on some speed bumbs / humps? (refer attached picture).

Note my car is ever so slightly lowered using Tein Flex Z Coilovers.

Thanks in Advanced

I noticed a rattle/vibration behind the dashboard near the doors after installing a B6A resonated lower downpipe. It went away though after a short while. I don't know what causes it. All clearances were fine and all bolts checked for tightness after inspecting the car on a lift. The Invidia exhausts could benefit from a flex pipe to mitigate vibration. In any case, the vibration went away and it all sounds great with no drone

 

[Noddy91]

Yeah those downpipes are resonator free. Talk to a chat bot, download an app to analyze frequency range during drone. Talk to chatbot regarding what length of resonator will be most effective for removing said frequency range.

Re: door rattleProlly gonna need a second set of ears to identify or show friend how to produce the rattle while you ride shotgun

Thanks - I'm looking into a J pipe, if the matter does not resolve on its as per
RZ34>Mk.V advice.

 

[Noddy91]

1) I just have AMS catless LDP noticed drone and vibration is worst in the first 2k-3k miles but smooth out over time. The muffler uses fiberglass packing that needs some wear in. Full catless will always have more drone on VR30.

2) I'm stock height and still think that section towards the back sit pretty low.

Thanks, this confirms the low exhaust is by design, not me doing things worng

 

[saltyz]

Yeah buddy. Works like active noise cancellation tech in headphones. Maybe look into the diffs in j pipe and resonators. One of the two maybe more effective for your scenario. Keep us updated. Itd be cool if you could do some recordings and show us data.


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