Hello,


I have been owning and (daily) driving a G37 Convertible since 2010.

My car only had a muffler change for years, it was the Meisterschaft muffler from "GT Haus", that made the exhaust note louder and lower. If you are curious, I had made a before-after video that can be found here :
Recently, the OEM front "Y" part of my exhaust line was damaged, and I figured that it would be a good idea to get the rest of the Meisterschaft line, so I ordered their front "Y" and mid sections.

The result is not satisfying. The note is even louder now (maybe too loud ?) but that is not my main concern. The surprise is that it is not as low now. It has become higher-pitched and more "metallic" (I believe the right word is "raspy" but I am not sure), especially in the mid-range of the RPM. Even from the cabin, I can clearly hear the difference and the noise is no longer pleasant.

I have not shot a video (yet ?) but the result should sound like what can be heard on this one (compare with my video at 1:31) :
I was wondering if a "bad" installation could be the culprit (I had it done at a local garage). If not... I need a solution and thought of different paths.

1 - Some people claim that resonated high-flow "cats" like those from Fast Intentions produce a lower note with only a slight increase of the volume. Would it work ?

2 - I could put the the OEM mid section of the line (which has resonators) back instead of the Mesiterschaft one (which does not have resonators). What would happen then ?

3 - I could put another aftermarket midsection that has resonators and is made with stainless steel, but I do not know any.

Can anyone please provide me with insight on these ideas, and/or suggest any other kind of solution ?

Many thanks in advance,


Sincerely,
Kaighal.


PS : I can shoot a video of the current exhaust note if anyone is interested but it will not be at the same place as the old one so comparison will not be perfect.

 

That sucks - Well I can tell you one thing for sure, if you remove your stock cats and add FI RHFC - your rasp will definitely increase

GT Haus has a signature metallic sound that most find exotic and it is also one of the loudest set up

I personally think Motordyne is the best sounding set up for our VQ engines. Maybe a XYZ pipe from motordyne can help ?

 

Nothing is wrong, sound is as intended.


i would suggest adding a resonator to your mid pipe or going back to oem y pipe

 

More rasp with RHFC ? Ah, I thought that the resonators were there to prevent that kind of noise.

Thank you for the suggestion, I contacted Motordyne on their website to ask for their opinion on the matter.


Ok, so nothing can be blamed on the installation, thank you for clarifying.

How exactly can I add a resonator to the mid-pipe ?

I cannot go back to the OEM Y pipe as it is the damaged one, however I can put the OEM mid pipe back (which has resonators) as GTHAUS claims that every part of their exhaust is interchangeable with the OEM line. But I am worried about differences in diameters (if any) and materials, would that not produce "droning" ? (here as well, not sure about the word)

 

Put the oem midpipe you will love it again. Not having the resonators to clean up the exhaust sound is causing the rasp

 

Thank you for sharing your opinion and knowledge

Do you have any idea of the difference between putting back the OEM midpipe and replacing the GTHAUS Y-pipe with the MotorDyne XYZ-pipe with the optional resonator, as suggested by 2011-G a few posts above ? (apart from the price, of course)

I wonder which solution would produce the lowest-pitched tone, the least rasp and the least droning (if any - I have none right now). Added benefits would be performance as I will probably get an ECU tune this year.

I found this video with the exact setup that I would have and it seems to still be somewhat high-pitched and raspy (there are a few other videos on the same channel) : .

 

No guarantee but the xyz resonator has been proven to decrease rasp however it barely lowers the sound levels. So if the loudness is. Bothersome id just put oem midpipe and be done. Or try it out before buying the xyz since you have the mid on hand.

 

Oh yeah, you should definitely test it out since you have the old mid pipe on hand - You have nothing to lose.

 

I will chime in too. I spend alot money tuning my exhaust to sound the way i want.
My suggestion to you is to add Vibrant Ultra Quiet Resonator in place of center flange. It removes most of rasp and will tone down exhaust note too.

 

Sell it and get the full Motordyne CBE

The last thing I would do is hack up that beautiful Meisterschaft exhaust.

 

Hey guys,




Thanks for all the replies. Here's a little update. Curiously, the sound has become less "metallic" in the mid-RPM range, precisely where it was bothering me. I thought I was simply getting used to it, but my wife confirmed.

Is it possible that the sound was different because of low temperatures (they dropped under 30 °F in France exactly when I had the GT-Haus extra parts installed) ?

And/or, is there some kind of "coating finish" in new pipes that alters the initial sound, then loses its effect after driving for a while ?

Is there any other explanation that you guys can think of ?




Anyway, the sound is better now but I am still considering the purchase of a MotorDyne XYZ pipe because cabin volume remains high at "unreasonable" cruising speeds (above 100 mph). Do you think the resonator module will help with this or is it unrelated ?

On the same topic, do you have any suggestion to reduce cabin volume ? I did some reading about isolating materials but it seems like a lot of trouble for minimal gains.




Once again, many thanks in advance

 

Jay Leno swears by DynaMat.

 

I had no idea who he was, Google taught me

I contacted the French DynaMat office, they said that I could put their product under the car for an easier installation, but that it would not help much in their opinion. If you have any thoughts on the matter... ?

 

Several G owners have used DynaMat. They remove the seats and carpet, apply the sheets and reinstall everything. I would assume the Dynamat would have a difficult time adhering to the dirty underside of your car.

 

shoulda went mxp