Can I add helmholtz after muffler?
 

I just added the borla Cat-Back system to my car and along with the unequal length header and the catless front pipe the car drones a lot between 35 and 4500 RPM

There's not much room to work with since my front pipe has two resonators on it already. Is it possible to add a helmholtz chamber after the muffler or will that be of no use?

I have the Borla catback and UEL Header with the factory front pipe. The drone is quite pronounced. I applied sound deadening mat to the trunk area to combat it, with noticeable effect.

Hey can you send some details of the sound deadening mats? I would love to get one as I have a 3" system catless and without any resonators. The Tomei type 80 is loud af

google automotive sound deadening, there are numerous products. most familiar being a roll of insulation with sticky stuff on one side that you line the metal frame with. 'dynamat' being a popular brand, but not the only

I used Stinger RKX36B Roadkill Expert Series Sound Damping. Easy to apply, I recommend using a roller tool to ease and improve the application. I added some to the top of the area where the windshield meets the chassis to prevent rattles from a subwoofer as well, and that did the trick for that situation as well.

Do you have any pics of your setup?

I'll get some this weekend.

Would like to see this, as well!

Here is a nicely detailed thread post for trunk sound barrier installation:
http://www.ft86club.com/forums/showp...56&postcount=5

Scroll past the headliner portion to get to the the trunk portion. I plan to do my trunk this weekend in a similar fashion.