Drone Resonance and more Droning Thread

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Dec 19, 2007 | 06:47 AM

#41

vegastrashed

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My Ride: 2007 E63 AMG | Obsidian Black | Schwarzes Nappa | Black BirdEye Maple | Premium II Package | Electronic Trunk Closer | Parktronic Engine: RPi/Powerchips custom ECU tune, RPi Ram Air Kit (BMC filter, scoops), RennTech Sport exhaust, secondary cats, charcoal and resonator delete, custom AAA x-pipe Exterior: 50% side windows / 35% rear window Formula One Pinnacle Series | Flat AMG hood emblem Suspension: Renntech Lowering Module Wheels/Tires: Radenergie R10, Falken FK452 245/30/20, Yokohama ADVAN Sport 285/25/20 ----------------------------------------- 2005 545i Sport SMG | Ti Grau | Schwarzes Dakota | Anthracite Maple | Logic 7 | Nav Engine: Custom AFE CAI, Superchips ECU remap, Sprint Booster, RDSport Dual Exhaust Conversion with Quad Pipes and X-pipe, 3 resonators deleted, 90mm tips! Exterior: M-Tech Aero kit | M5 Mirrors | M5 Rear Bumper | Trunk Lid Finisher | Vorsteiner decklid spoiler | 50% Formula One Pinnacle Tint Suspension and Brakes: Bilstein PSS9 coilovers, JBT BBK: 16" cross-drilled rotors, 8 piston and 15" cross-drilled rotors, 4 piston Wheels: VIP Modular VR 02 20x9F, 20x10R | Toyo T1R 245/30/20F, 285/25/20R Lights: PIAA 4150K Xtreme White Plus fog lights, AIB v3 MOST IMPORTANT: Hardwired V1; =) ED Date: 4/7/05, Re-delivery date: 5/21/05

Similar too what you posted. So, Matt@Remus do you think either insert will cancel out the resonance?

Drone Resonance and more Droning Thread-cone.jpg

Dec 19, 2007 | 06:58 AM

#42

nigxdoof

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From: NYC, Rego Park, Queens

My Ride: 2004 E60 530i, 2012 E70 X5 35i

Model Year: 2004

Quote:

Originally Posted by vegastrashed' post='508428' date='Dec 19 2007, 10:47 AM

Similar too what you posted. So, Matt@Remus do you think either insert will cancel out the resonance?
Attachment 42041

Hehe, you know, just off the topic, but all these "devices" you guys are posting up just look perverted..

.. HAHAHA.

But, on a serious note, if you put these cones before the xpipe, how much of the resonance will be removed? I would like to try this too.

Dec 19, 2007 | 07:06 AM

#43

CampioniShop

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Not sure about the one you posted, but ours is to reduce DB output on our WildLabel exhausts to make TUV approved, a rigorous sound test in Austria.

The one you posted looks like a huge restriction.
We're not really believers in such methods, we do it just to meet requirements, otherwise it's a ghetto way to solve an engineering malfunction.

Dec 19, 2007 | 08:15 AM

#44

rodybmw

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Quote:

Originally Posted by vegastrashed' post='508384' date='Dec 19 2007, 01:30 AM

I should be asleep but the droning issue has consumed me. I've gone through many car forums and somehow came across the Dynatech Vortex Insert Cone. You can read up on what a CTS owner did here with the cone. If you google "Dynatech Vortex" there's a lot of examples in the Mustang, Nissan Titan, and other forums. So, what do you think B32 and rody about this Vortex insert cone as a resonance neutralizer?

Joe.......they say that it reduces dB's (sound level).....so does it reduce only the droning sound level without affecting the overall sound level of the exhaust?.......or does it reduce the droning BECAUSE the overall sound level is reduced?

Dec 19, 2007 | 08:58 AM

#45

CampioniShop

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2nd option

Dec 19, 2007 | 02:09 PM

#46

Bimmer32

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My Ride: 2005 BMW 545i, Silver Grey, Sport Package, R. Shades, Cold Pkg, Sat. Rad., Prem. Sound.

Quote:

Originally Posted by RemusExhaustShop' post='508490' date='Dec 19 2007, 11:58 AM

2nd option

Agreed. Remus's pic of the muffler silencers is effective because it actually create a small outlet for the exhaust; thereby, speeding up the velocity of the gas. Additionally, the perforated holes (some don't have it at all) and the flat facing plate actually creates a side resonator effect. The sound trips down the spaces between the outer and inner tube, bounces 180 degrees back and cancels out the sound. The inner opening travels through; I think it lowers the db level by up to 5 db as some manufacturer climb.

As for the Dynatech Vortex, I have not experience with one yet, though, I'd love to try it, but they don't have anything smaller than a 3" diameter. MY tubing is only 2.25. Darn.

You know, this is no different from rolling light steel mesh in a cone shape. The manufacturer claim 1-3 db reduce.

Does it have any sound absorbing material?

Dec 20, 2007 | 11:33 AM

#47

vegastrashed

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From: San Diego, CA

Okay, out with Madonna's bra (Dynatech Vortex) and in with Dynomax bullet resonators to eliminate the drone. http://www.dynomax.com/products/raceseries.html

Dec 20, 2007 | 02:22 PM

#48

Bimmer32

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My Ride: 2005 BMW 545i, Silver Grey, Sport Package, R. Shades, Cold Pkg, Sat. Rad., Prem. Sound.

Quote:

Originally Posted by vegastrashed' post='508871' date='Dec 20 2007, 02:33 PM

Okay, out with Madonna's bra (Dynatech Vortex) and in with Dynomax bullet resonators to eliminate the drone. http://www.dynomax.com/products/raceseries.html

Yeah, screw the drone. Let the bombs be heard.

Dec 20, 2007 | 02:40 PM

#49

vegastrashed

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Okay, that doesn't sound too encouraging. I hope you're not mistaking bullet resonators for a cherry bomb. I've read in the M5board where a member installed two bullet resonators to QUIET his Eisenmann Race exhaust with stock section 1 (secondary cats) and 2 (resonator) on his E60 M5.

Dec 20, 2007 | 02:49 PM

#50

vegastrashed

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Great.... I found a website that shows an example of a cherry bomb muffler and it looks exactly like a bullet resonator! I give up. The stock resonator is going back on.

http://auto.howstuffworks.com/muffler5.htm

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