Helmholtz length

Anybody have any idea how long a helmholtz resonator should be for the stock tailpipe? I recently did a direct muffler swap with a Carven TR muffler, but I'm getting the expected drone due to the stock tailpipe. I love the sound, but I knew the drone would happen.

No disrespect to Keith at DD, but I have the means to build and attach a helmholtz resonator myself for significantly less money. I just don't know how long the pipe length typically is to counteract the correct wavelength.

 

Why dont you hit up keith? I'm sure he'll help you out with the info.

 

It just seemed like a disrespectful thing to do since I don't intend to buy one from him. I love that he builds them for our community, but I just can't spend $200 when I can build it with scrap pipe I have.

 

I have 2 of his resonators in my garage. Tried to sell but no takers.

About 26" long and 2" diameter.

 

Okay thank you. If you want to sell one of them super cheap it looks like you're pretty local to me! I'm in Abington. That way at least they'll be stainless instead of some mild steel. And I might not actually have any 2" lying around currently....

 

What's super cheap? You can PM me if you want.

 

PM sent

 

Have any pics or videos of the carven muffler swap? Ive been thinking about just running a y-pipe to a single carven TR. What size muffler did you go with the 2.5" or 3"? I've got a 3" AFE catback and was wanting to go back to the stock size tailpipe to hopefully get some low end back. Wonder if I could just have my stock tailpipe retrofitted back to the AFE muffler...

 

I can get some pictures later today, maybe a video. I currently have a 7 week old baby asleep on my lap and she's been up since 3am....so I'm not moving a muscle!

I went with the 3", and found a stainless 2.5 to 3" Y pipe. I know the stock pipes are odd ball sizes, but they are pretty damn close so everything worked very well. My friend/installer had no issues lining everything up.

I love the sound, it is nice and deep, but pretty tame which is what I wanted. The only downside is the drone, as mentioned.

 

What y-pipe did you go with? i've been looking at the magnaflows. have you been able to drive on the highway much with your new setup? I've noticed with my AFE kit my truck seems to downshift more frequently going up the same hills to and from work on the highway.

 

PM sent.

 

I once saw a video about how to make a resonator. There was many maths involved in determining the size. I'll see if I can find it again and repost.

 

That was fast. I believe this was it.

https://youtu.be/ekJy78e9QIk

 

I went with this one I found on Amazon:

$31 TOTALFLOW TF-SY3025 409 Stainless Steel 3" / 2.5" Y-Pipe-3" Single / 2.5" Dual (Inner Diameter)

https://www.amazon.com/gp/aw/d/B07BK5H4DT?psc=1&ref=ppx_pop_mob_b_asin_title

Quality was nice and it was exactly what I needed. The stock pipes are a little wider than the Y, but there was enough movement in them it didn't cause a problem when he lined everything up.

I haven't noticed any issues with downshifting excessively or behaving strangely. I did have it on the highway for about an hour, then a few small trips around town. Asolutely no extra piping was used, just the Y and the muffler. So I imagine it freed up the engine fairly well but didn't mess with back pressure much at all.

I'm heading out in a few, so I'll grab some pictures then.

 

In it for pix.

 

Here are some pics

 

Thanks for the photos

Would really like to hear how it sounds!

 

Just a heads on adding a Helmholtz resonator to an aftermarket muffler;
When I bought my 2014 I wanted more exhaust sound.
Went to a local muffler shop, they put in a 2 in 1 out Maganflow.
Sounded great in town, had the drone from hell on the highway.

I then learned about Keith @dirtydeeds and he suggested just buying and trying his Helmholtz res with the Magnaflow.
Got it, installed it, and it did indeed kill the drone, but it knocked the sound of the magnaflow back down to stock muffler levels.
Truck sounded stock again.
So I had Keith make me a custom 7 inch and ran it for 3 years before swapping it with his 10".

I've posted this before and some are convinced the res wouldn't change the sound of the muffler.
Well, it did, I lived it.

I really don't feel Keith would be offended if you reached out to him.
He isn't like that, he is very helpful.
He talked with me years ago when I had questions about installing 6112 or 5100, knowing I was going to buy them elsewhere.

Good luck..

 

That is good advice. I have heard similar stories about the resonators as well. I guess I just have to roll the dice. Worst case, I'll swap out the TR version for a R version to pick volume back up!!

And I'll reach out to Keith of needed, I just didn't want to bother him if I wasn't buying from him. It looks like in a week's time I'll have a resonator on and I'll report back.

And I'll work on getting a sound clip soon, bit it might not be today.

 

The Carven TR is a straight through canister style packed muffler similar to the one’s Keith builds. I looked it up, the dimensions are 15x5, so it seems like it would be comparable to a 7 or 8 inch standard system since he puts 2 canisters in the system.

 

Any considerations for x-pipe?

 

That's good to know. I was always curious what was inside his mufflers. I assumed they were straight through with some sort of packing, but I've never seen any pictures of it.

 

I don't know, I had no need for one because I was going into a single muffler. I know Carven makes an x-pipe now, but it is only in 3" which isn't ideal for our exhaust.

There are probably quite a few 2.5" x-pipes on the market you could find.

 

Good to know, thanks.

 

Sorry I missed this earlier. I'll try to get some sound clips together. Tomorrow I may run out so I'll try to get some then. I've been getting cabin fever because of this lockdown....

 

Did you ever get the right dimensions and install the resonator?

 

I did not measure it, but I can go out and get some measurements and pictures this afternoon once it dries up a little. The install was fine, I added some RTV just to make sure it had a nice seal. And it did make a world of difference cutting out the drone. Keith definitely found the secret sauce to these trucks when it comes to knocking out the drone.

And I'm still really happy with the Carven TR muffler. Sometimes I wish I had went with the R, but honestly I like how it's very deep and mellow, but then makes some noise only when I want it to. I do tow a lot, and honestly I don't miss the days of my super loud first gen Tundra just roaring when I had a heavy load behind it.

 

I just ordered one from Keith. Currently have a flow master super 50, but with the DD resonator on the tail pipe I figure I can change out mufflers and not have to worry about drone at all.

 

Yes you shouldn't have a problem at all if you want to swap out mufflers. Regardless of what muffler you have on, the specific wavelength that is causing the drone is counteracted by the resonator. I'll try to get some pictures today, it was wet all day here yesterday and I just didn't feel like crawling under the truck.

 

@Hugemoose are you still around to update your diy heimholz resonator? I'm looking into the Carven TR also. Want to get all my apples in a row before chopping of my muffler.