Exhaust Drone

[93SVT#18]

Just installed the Magnaflow Catback with 3" pipes and have a ear drum hurting drone when pulling a hill at about 1700-1900 RPM. Is there any solution to this. Will a high flow x-pipe fix this or long tubes with x-pipe. Will this get better as they break in or is there anything that can be done.
Thanks

 

[jcthorne]

Wrong exhaust for the car. You should have installed one tuned for the GT500 and not just a GT.

 

[eichisama]

Downshift!

 

[03dsgcobranc]

sounds like some kind of resonance or exhaust signals bouncing off each other. I would try an x-pipe, it may smooth everything out.
found this on this page
http://www.bimmerperformancestore.com/exhaustdrone.html

Drone in the exhaust is due to the engine driving the exhaust system at its resonant frequency. You can't get rid of it, any length of pipe has a natural frequency, but you can change the frequency (RPM) it happens at. Stock exhaust systems are tuned to put the resonant frequencies outside the normal RPM range the engine is run in. Sometimes they add resonators for this purpose.

To raise the resonant frequency of a system, shorten its length. To do this, you can try tail pipes that exit by the wheel (like GN's have), or you can try a muffler with a shorter internal flow path. If you have a true dual system, you can change the natural frequency of the system dramatically by adding a balance tube. If you can't shorten the system, then you can add slightly less than one wavelength of pipe. This will also raise the resonant frequency of the system.

 

[93SVT#18]

Wrong exhaust for the car. You should have installed one tuned for the GT500 and not just a GT.

According to Magnaflow this system is for the GT500. Granted all the catbacks will fit either the GT500 or the GT because the are the same after the cats as one another.

 

[wildosvt04]

GT500 has an x-pipe. Ive heard the solution is gears!

 

[Stripe Delete]

Wonder if the Magnaflow (axlebacks only) will drone. I really like these but dont wont droooooooone.

 

[jcthorne]

If the Magnaflow's drone, they were neither tuned nor designed for the GT500. There is a big difference between FIT and Designed for.

There are properly designed kits for the GT500 now that do not drone. Sound quality is a matter of preference. As the GT500 already has an X, adding one will not help. Headers will change the natural frequency also.

The GT500 is different from the GT in tuning and flow.

 

[Boomer v3.8]

I have an 05 GT with a droning Borla S-Type exhaust, got the FRPP XPipe and it just increased the volume of the drone! hehe

I don't mind it, but sometimes it can be unbearable....
I just downshift and drive around the drone...

 

[VNMOUS1]

GT500 has an x-pipe. Ive heard the solution is gears!

My 3.73's solved the problem at those speeds.

bj

 

[chuckstang]

A drone to me signifies cheap and childish. My 95 GT with flows droned bad, but my Cobra with flows does not drone at all. I think it is because I also have an X pipe on my cobra and it sounds amazing.
If you replace the stock X on the GT500 it could still change the sound because the stock cats choke most of the sound and not all X's are the same in shape or design!

 

[jcthorne]

Might this and might that. Why spend money to fix a poorly designed aftermarket part. The correct parts exist from several vendors that sound incredible and perform great.

Dump the magnaflows and get something designed for the application rather than a band-aid.

 

[Wiseguy]

Corsa = no drone...

 

[jcthorne]

Corsa = no drone...

As well SLP and others.