[Robstevens]

Hello I have a few questions regarding this exhaust for the 6 gen Camaro - dont really care what version (axle vs CB). What I'm really wondering is do the Helmholtz resonators do their job in eliminating drone around 2000 rpm?


Also wondering if anyone could give me the dimension of the resonators (dia + length) plus the same for the pipe that attaches the resonator can to the main 3" exhaust tube.


I have the same engine, but in a project car that cannot use the MBRP directly as it wont come close to fitting.


I thought about taking a stab at sizing my own, but I would guess MBRP has put more research around temps, HZ and such.



RS

[wise]

I have the MBRP catback installed on my car, along with secondary cat delete. I have zero drone at cruising speed in any RPM, however the exhaust does hum if I lightly accelerate in higher gears at highway speed without downshifting. I definitely wouldn't consider this drone or anything near it though.

I've had other vehicles with different aftermarket exhaust setups that did drone so I am all too familiar with it. I see your user details mention a Porsche 996 with an LS3. If this is the car you are working on, the target RPM range of drone could vary. I'm assuming your overall exhaust length will be much shorter than a full length catback. There was a lengthy thread at one point on Camaro5 where users were testing different lengths of helmholtz pipes that may be more useful for your purposes. Thread links here: https://www.camaro5.com/forums/showthread.php?t=102075
https://www.camaro5.com/forums/showt...ight=MRT+drone

I will try to get you some measurements on the MBRP resonators and pipes in the next few days. I would say for rough estimate though the resonators are approximately 4"-5" in diameter and 12"-14" in length. The pipe that connects the 3" exhaust tubing to the resonator appears to be 2"-2.25" in diameter.

Good luck with your build! I attached two pictures of my exhaust prior to install just to give you an idea.

[Robstevens]

Thanks for the response Wise - much appreciated. Nice car as well.


I think I've read every Helmholtz article on the web at this point. The calculations and construction are fairly straightforward, but the biggest unknown that affects effectiveness in the calculations/construction size is the temperature component. I'm unsure whether the reference is in the dead leg resonator or the flowing main exhaust. I assume MBRP has measured this and constructed their resonators accordingly. I also think the influence of temperature is why you see people reporting hit or miss results sometimes when they make their own resonator - it doesn't get measured and taken into account. The store bought solutions are always successful, unfortunately in my case I cant make any of them work.


As for exhaust length, I thought that may also come into play, but after using various software to profile the sound spectrum, I get the same magical dB spike at ~+/-2000 RPM (drone) as everyone else. It would seem that the sound profile is driven by the displacement/type of engine and its resulting harmonics.



Anyway would be a great help if you can get the measurements of the resonator cans and the attached necks. This will be a fab once and pray it works adventure, so want to try and get it right the best I can. Also would like to stop the ringing in my ears....

[VinnAY]

DO I see that right as it's basically the resonators and otherwise a muffler delete...? I had MBRP on my Mustang and keep looking at an axle back on the Camaro but by the looks of it would seem very aggressive like a race vs a street system.

[Cichoskiss]

Originally Posted by VinnAY

DO I see that right as it's basically the resonators and otherwise a muffler delete...? I had MBRP on my Mustang and keep looking at an axle back on the Camaro but by the looks of it would seem very aggressive like a race vs a street system.

Yes you got it. I have it with kooks headers I will say no drone at all. But it can get very raspy with low rpm while in higher gear. It is the best bang for buck if you want loud tho.

[MP3BOOSTED]

if you want to hear how it sounds cammed check out my youtube channel https://youtube.com/MP3BOOSTED

[Robstevens]

Anybody with this exhaust able to get me dimensions I'm looking for?

[Robstevens]

Anyone have sizing of the Helmholtz resonators for this? My car going into the shop next week.

[JSH]

Originally Posted by wise

the MBRP resonators

Those look like Helmholtz-style resonators to me. I would like to buy those for my AB. BTW, the science is that the res. pipe should be attached at 90 degrees to the exhaust pipe.

[JSH]

Originally Posted by Robstevens

Anyone have sizing of the Helmholtz resonators for this? My car going into the shop next week.

Every shop seems to have been at SEMA this past week, but I've emailed and will call Kooks and others next week about buying a set of Helmholtz resonators w/pipes. At a minimum Kooks and others should be able to provide us with the sizes/spces.