HelmHoltz resonator - No more drone !

[F150Feste]

A while back, I asked a local muffler shop about the Hemholz resonator and got a similar response. They essentially said, get me specs and I cam make it.

Question; did you experiment with other lengths since you made it adjustable? If so, any difference or did you stay with the 28" length? I dont suppose it would matter, but do you suspect any tuning/drone difference with this length for us normally aspirated Raptor guys?

I did a little and each produced a bit of drone protection in different RPM ranges (just a few though from 26.5 to 30"). Since here in Texas the speeds are a bit faster on the highways I pushed it in to 27" length and it seems to cover the 1800-2100 rpm range fairly well. Still have just a hint of resonance occasionally but much better than without and is tolerable (vs without which was intolerable to me and my passengers).

 

[Canuck714]

Im about to modify my Roush system to get the drone out. Unfortunately I have not found an exhaust shop here in San Antonio that :
1. Knows what Im talking about...lol
2. Keeps 409 stainless in stock with a mandrel bend to make a J
3. Doesnt think the Helmholtz will do anything so why bother....

 

[t_j]

Im about to modify my Roush system to get the drone out. Unfortunately I have not found an exhaust shop here in San Antonio that :
1. Knows what Im talking about...lol
2. Keeps 409 stainless in stock with a mandrel bend to make a J
3. Doesnt think the Helmholtz will do anything so why bother....

FYI 409 will get surface rust (similar to the way aluminium oxidises) so it will end up looking like the OE piping. Better off with 304 if you can find it (though mine was 304 guess its 409). I got my parts through summit (except for the plate for the cap that I picked up locally):

https://www.summitracing.com/parts/sum-640125-1

https://www.summitracing.com/parts/sum-622003-ss

 

[dirtydeeds]

Give me a call. I can preamble a j pipe. Bent. Cut. Notched. And capped. Right out of 304 SS.

760-877-4234

---------- Post added at 11:53 PM ---------- Previous post was at 11:53 PM ----------

Not on the site. But a lot of cool examples are. DIRTY DEEDS INDUSTRIES – Performance Sound without the Drone

 

[Canuck714]

Left you a voicemail Dirty... Ill take you up on that offer.

 

[dirtydeeds]

Left you a voicemail Dirty... Ill take you up on that offer.

Returned. Hit me back with any questions. Thanks!!!

 

[F150Feste]

Im about to modify my Roush system to get the drone out. Unfortunately I have not found an exhaust shop here in San Antonio that :
1. Knows what Im talking about...lol
2. Keeps 409 stainless in stock with a mandrel bend to make a J
3. Doesnt think the Helmholtz will do anything so why bother....

None of the shops around me knew anything either, so I did some research on a reputable muffler shop who did other custom work and showed them my plans (on paper) and they worked with me during the fabrication of it and got it done in less than an hour. The helmholtz helped a lot, but didn't make it completely drone free (still tuning it though with the adjustable lengths). I might eventually just go with a better muffler like Borla or MF and just have it be a little longer to absorb the resonance and still be loud on throttle.

 

[Yeldarbraptor]

I know its an old thread, but figured I'd post my experience here if it could help anyone.

I recently bought my 2014, and discovered that it already has SW high flow catted headers mated up to a flowmaster catback. This combo drones like crazy in the 1500-2000 rpm range. Worst drone I've ever experienced. I'll be replacing the muffler at some point for sure, but in the mean time, I wanted to get rid of as much drone as I could.

I took it in to a local muffler shop with a drawing and some measurements, and they were able to fab something up for me pretty quickly. I went with a 2.5" pipe that measured 26" going around the outer edge. Its mated to the resonator delete, so if I decide to go a radically different route later on, I can change it up fairly easily.

Even after reading everyone's experience here, I'm surprised at how well this works. It's not perfect, it's not the prettiest, but its a huuuge improvement from getting my eardrums vibrated to hell.

Yet another awesome fix facilitated by this forum. Thanks all!