Slip-on turn down tip recommendations for BW exhaust?

[SQ13]

Hey guys. I’m looking to drive at Harris Hill soon, which has a 99 dB limit trackside and an 85 dB limit at the property line. With the BW exhaust, I know I’m going to get flagged, so I’m trying to find a slip on turn tip that I can attach when I drive at Harris Hill. All of the tips I find are really long, so I was wondering if any of y’all are running one that is shorter. Or, would you happen to know where I can find one that isn’t like 10” long? Thanks.

[foolio]

Good question. Going to be watching this. I just got a Bimmerworld race (resonated) and it’s loud AF. I forgot about having something ready for tracks with DB limits.

[SQ13]

Good question. Going to be watching this. I just got a Bimmerworld race (resonated) and it’s loud AF. I forgot about having something ready for tracks with DB limits.

KenO from M3F gave me a good idea on Facebook. His setup allows him to go from 102dB to 95dB. He attaches a small muffler to the M3’s exhaust tip, and on the other end of the muffler is a turn pipe that has dB killer with packed material in it. I think I’m going to replicate that.

Muffler: https://www.speedwaymotors.com/Schoe...ler,57016.html

Exhaust elbow that I’ll likely go with: https://www.speedwaymotors.com/Mild-...Inch,9757.html

Edit: I think the length of the flange on the muffler will be a problem. Pretty sure the BW exhaust tip is slanted (can’t confirm bc I don’t have the car with me), so the flange will probably be too short.

[SQ13]

After talking to some people, I think I’m going to use V-bands. I’m going to cut the exhaust tip off and add a V-band flange to the cut ends, as well as the additional muffler. That way, if I need to use the Laguna pipe I’ll just remove the exhaust tip and install the muffler. Muffler-to-elbow will most likely still be held in place using a couple of bolts.

[SQ13]

I ended up going with the setup mentioned above—extended muffler + turn tip. The muffler is attached to the BW exhaust using a V band. The turn tip was cut to remove excess piping, and it is tack welded to the muffler. It’ll be getting a V band setup as well, in case I ever need to use a turn tip but not the muffler. The tip does not have dB killer in it. Still, the exhaust is significantly quieter..similar to my old SS Race muffler with stock mid pipes and CPI headers. I can probably have an instructor in the car and be able to hear him/her clearly. I’d still wear earplugs though.

My concern at this time is the lack of a support bar for the muffler. I’m a little uneasy about having the muffler secured by just the V-band given the muffler’s weight (may be overreacting here). Plan on getting that done hopefully soon. Also, if you cut the turn tip like I did, make sure you smooth out the cut pipe very well. I didn’t have mine smoothed out well enough and cut my leg while washing the car.

[Feffman]

I did a Dynatech turn down with an internal baffle (link below). Haven sound tested it yet, but will do so at NCM in April.

https://www.summitracing.com/parts/dtc-780-01200

Feff

[rnh204]

Great thread. I’ll look at doing something similar over the winter for the tracks in the NE that have db limits. SQ13 what is the lowest sound limit you’ve passed at?


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[MD_M3]

So on my muffler I have a 3.5" ID and we made 4 slits on the muffler and use a clamp over it so we can swap tips form a straight pipe or an angled pipe to make sound.

[SQ13]

Great thread. I’ll look at doing something similar over the winter for the tracks in the NE that have db limits. SQ13 what is the lowest sound limit you’ve passed at?


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Sorry for the late response. The only track I’ve driven at that has sound restrictions is Harris Hill:

“A decibel limit of 99db trackside and 85db at the property line will be enforced at all times.”

No idea if they were actually measuring, but they have kicked out people in the past for sound. I was safe, and the owner of the track actually took photos of my Laguna pipe and thanked me for being considerate.

[bigjae46]

Bruh...some lotion! 🤣🤣🤣

Great work...I might copy that. I keep hearing rumors that Cresson actually has a noise limit but they don’t enforce it.

Now...there are houses going up around there (besides the trackside villas). Just a matter of time...


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[TrackTracktor]

I did a Dynatech turn down with an internal baffle (link below). Haven sound tested it yet, but will do so at NCM in April.

https://www.summitracing.com/parts/dtc-780-01200

Feff

Is it noticable on the street, wouldn't mind one for driving to the track.

[Feffman]

Is it noticable on the street, wouldn't mind one for driving to the track.

On my short test drive near our home, the turn down helped significantly.

[TrackTracktor]

On my short test drive near our home, the turn down helped significantly.

How did you attach it? I got one but am unsure of how to mount it.

[SQ13]

Maybe this

https://www.amazon.com/gp/aw/d/B07S4LMKZH?psc=1&ref=ppx_pop_mob_b_asin_title

[TrackTracktor]

Maybe this
https://www.amazon.com/gp/aw/d/B07S4...b_b_asin_title

Its slip fit, going to try a large hose clamp but was hoping there was an official solution.