• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

Severe drone at 2.5k rpm after middle muffler delete.

spock345 said:
...experimenting with a few weights on the exhaust or the vibration absorbers ...I can actually leverage those college physics classes now..
Click to expand...

It interested me to see in the link by Trieb that the part number for the exhaust dampers had a Hertz frequency listed.


I see those weights all the time working on modern cars. They even have em dangling off the back of transmissions sometimes. I have seen em on Fords and Nissan, I think.... and on BMW exhausts from early 2000's.


Here is my regurgitated google link during 10 seconds of searching. Talks about sound frequency of exhaust notes:

http://www.caranddriver.com/features/this-is-why-various-engine-types-sound-so-different-feature
 
The factory resonator was in there to reduce that drone.
Easiest way to fix it is to put it back in there. You won't notice the .25hp it cost at the wheels.
 
What about a Test Pipe+Turbo Muffler, that would give a good tone while not being too loud right?

Specifically flowmasters turbo mufflers are pretty good at quieting the exhaust. You can basically put a test pipe all the way to the muffler.
 
Last edited:
I am currently running no mid muffler on my car and am using a Thrush resonator ($30 @Vatozone) in the rear muffler location with zero drone at highway speeds.
 
Triebwerk said:
Some people with sport exhausts install vibration absorber which can be found on a lot of modern cars (BMW, Audi) and they seem to work.

Example No 10
http://www.etkbmw.com/bmw/EN/search/selectGroup/50329/18_0561/18307795604

BMW 330i No 20
http://static.bmwfans.info/images/epc/MTU2MDY5X3A=.png

Installed one a few days ago but test drive not yet done...
http://www.bilder-upload.eu/show.php?file=582bae-1484637764.jpg
Click to expand...

Now that makes all the sense in the world. I suppose it works much like bar end weights on motorcycles.
 
Actually just clamping a small weight to the straight pipe where the resonator was moved the RPM at which the drone occurs in such a way that it doesn't drone while doing 65 down the freeway.
 
I am going to go turbo muffler flow master with test pipe, and get rid of my cat. (sorry to all the tree huggers).

Will let you all know how much louder it gets
 
Fumomike said:
I am going to go turbo muffler flow master with test pipe, and get rid of my cat. (sorry to all the tree huggers).

Will let you all know how much louder it gets
Click to expand...

Can't get rid of my cat here in California. Although it is more pleasant to be downwind of the tail pipe when compared to the crap the pre-smog restrictions cars kick out.
 
JW240 said:
Nice. Curious about the results. Need to replace the exhaust cat-back on mine, will do stainless steel, maybe this helps if i run into a small drone problem. I imagine the Helmholtz (1/4 wave) resonator is more effective then.
Click to expand...

My car is still not running (don't find the problem) but we installed one of this vibration damper to a Audi A4 1.8t 3" stainless exhaust and 400cpi sport cat who had a sirious drone problem and after a test drive today with me sitting in the front and back I can say, it works great! Drone has disapeard. I have never expect that it will perform that well. If it has the same effect at the Volvo I would be more than happy.
 
Fumomike said:
I am going to go turbo muffler flow master with test pipe, and get rid of my cat. (sorry to all the tree huggers).

Will let you all know how much louder it gets
Click to expand...

Doing your little part to make the world worse for the rest of us for no damn good reason. Check.
 
You must log in or register to reply here.
Back
Top