some muffler advice?

georgeleedom · Post by **georgeleedom** » 07 Feb 2011, 06:42

I recently put in a 2.5" OBX exhaust with a 3" pipe. I added a 2.5" cat, because I have to pass emissions inspection every two years. I love the sound when I'm getting on it, but cruising at highway speeds or driving around town I get a pretty bad drone. I'm am way not interested in sounding like a honda.

I'm not certain I have enough room, but I may be able to add a resonator, glass pack or additional muffler. My other choice would be to change the muffler that's on there now.

Of course I want it to sound like a 428 and know it never will, but it's got to sound better than it does. I welcome all your suggestions.

Thanks, George

Post by **JRL** » 07 Feb 2011, 15:17

Wrong exhaust
I have the EST performance exhaust WITH THEIR REAR RESONATOR REMOVED
and it's a real nice sounding Volvo WITH NO DRONING whatsoever!

endothrow · Post by **endothrow** » 02 Mar 2011, 08:07

It might be a combination of the tune with the OBX exhaust. I think that the EST would be a better choice, but since that isn't an option, have you considered installing the factory catback and then adding a glass pack inline or something? The factory resonator sounds pretty smooth on my 5 cyl. with the OBX DP and I get really nice turbo spool on my 16T with factory catback and resonator.
Maybe not what you are looking for, but I am also interested in adding a glass pack inline on the factory catback so I will be watching this thread.

georgeleedom · Post by **georgeleedom** » 02 Mar 2011, 11:34

I appreciate your thoughts and I've considered something along those lines. One problem is the factory exhaust has a pretty extreme bend near the muffler. Also it's 2.25" and the bigger the better when it comes to a turbo. (I know people on here will argue to death about back pressure, spool times, etc.) but I spoke directly to an engineer at Greddy and he said no such thing - bigger the better. Vent it right out the fender if you can.

Anyway... The OBX has a resonator which is about 6" long. The muffler is a straight-through cylinder 6" diameter and about 18" long. With the race cat in there and the geometry of the OBX system, there's really no space to add a resonator. My only choice at this point is to try a different muffler. An oval muffler won't fit, so I'm looking for as quiet a round muffler as I can get. I am interested in people's thoughts regarding turbo-style versus glass-pak, versus chambered. I've heard a Gibson is quiet relative to most others and magnaflow is also good.

I'm still looking for input and will keep the thread updated as well. Thanks.

Post by **JRL** » 02 Mar 2011, 14:57

Seriously, I don't think you will solve your problem
This is inherant with 3" exhausts on Volvos...the DRONE and the only way you will get totally rid of it issmaller tubing
If you keep resonating it, you may get rid of the drone and have a more INefficient exhaust byt the time you're done