Fixing The Drone

[Harp96sho]

I don't recall seeing any graphs, but if you read through the thread, post 6 shows the formula and some of the other posts show things like how to find out the frequency and such.

 

[Eric Morris]

This "drone fix" is a Hemholz resonator.

Here it is on a commercially sold system:
http://dirtydeedsindustries.com/product/ford-raptor-system/
Notice the capped off pipe. That is the resonator.

The length of tha t capped off pipe needs to be tuned to the specific resonance or "drone" of each particular exhaust/engine combo. You see similar dead end off pipes on intakes for new car engines for the same reason.

 

[Harp96sho]

For those who may be interested, I am selling the system I talked about earlier in this post. Classified link is here: https://shoforum.com/index.php?threads/gen-4-mrt-exhaust-with-helmholtz-resonators.143016/

 

[SilvererSHO]

I'm curious if you have tried varying the lengths side to side since the side coming from the front bank is so much longer than the rear bank.

 

[Harp96sho]

I didn't. I also thought about that but left it alone because the drone was mostly gone. Curious!

 

[Harp96sho]

For those who may be interested, I am selling the system I talked about earlier in this post. Classified link is here: https://shoforum.com/index.php?threads/gen-4-mrt-exhaust-with-helmholtz-resonators.143016/

System SOLD

 

[Dahctor]

I just wanted to thank this thread and SilverSHO for saving my exhaust. I performed a muffler delete and certain times it was really bad but I loved WOT. I just happen to work for a tube fabricator. Went with a little different setup, didn’t drop the exhaust to install. Really helpful thread. There is a before and after pic

Not nearly as neat as others but now sounds great at all times to me. Thanks again.