Hey guys i need to get rid of some drone and after doing research i seem to come up with a different answer everytime for the length of a helmholtz resonator. I know for trucks it is usually in the 26"-28" range but those are v-8's. I was wondering if anybody knows the math or can do it, to figure out how to eliminate drone at 2500 rpm in our v-6's. I'd really appreciate if somebody could figure this out for me because ive been going crazy trying to figure it out, and i dont want to dump money at a shop for this. Current projections for the resonator as calculated by me are 22" long. If anybody can comment on this please help me out! Thanks in advance!

 

So you have no cats? stick a dynomax resonator on it (24235)

 

Theres a long ass thread with all the info you could ever need to figure out the best way to calculate what you need for your exhaust. I you have no cats you will probably need a 26ish inch resonator

 

I have no drone. And no cats. Though I have no idea what resonator I have. The exhaust flows really well and is super quiet, and again no drone.

Unknown (truck?) resonator in place of the 3rd cat, Dynomax VT inplace of the mid muffler and two dynomax superturbos out back. Video will be up soon if you want to hear it.

 

Go to 5 minutes to hear highway. I do a wot run a little later on.

 

I have cats and i already have a dynomax in

 

I went to one and followed the directions but not everything was explained at the end of the calculations there was a random number to divide by which was never explained, I know all the trucks use 26in so maybe ill just try it out haha

 

MY exhaust is basically cats, with only one dynomax resonator in place where the stock resonator use to be. The rear mufflers and mid muffler are gone. I dont want to take cats out, but i love the sound i have right now and i dont want to change it so new mufflers arent really an option