Sound Shenanigans

[Wheelman_13]

So, I'm back. (living in Knoxville again) and would like to start making some events. However, I know (pretty much no question) that the NSX won't clear sound at Pellisippi. Do we have a go-to guy/shop/solution these days? I've seen mention of augers and supertraps. My current tailpipe needs a little work as it is, so if we know someone who could cut it up, surgery some sound abatement in and button it back up neatly, I'd like to get on that soon-ish.

Many thanks, and look forward to seeing most of y'all again soon.

-Richard

[oldmuscle69]

Well welcome back ya dick, just go to that guy near Winston rd by the mall or the guy on magnolia not far from pizza palace.

[jcox07]

You can message eric Anderson and ask him what he did to make the miata so quite or Jon Coatney may be able to help you.

[steverife]

I don't think any mid- engine guy can do what Eric did...

[TedV]

If the NSX has a trailer hitch he can use it to hold what Eric did

[MikeKelly]

Further research:

I can provide 2 - 4" Supertrapp units for testing at the August 28th event.

They are rated for 250 hp each.


Anyone who wants to test one needs to provide a 2.5" O.D. (one or more) exhaust tube(s), which can be drilled + riveted, clear of their bodywork(to avoid melting, see illustrations below).

I will provide the rest (quantity available = 2, you may have to share)...



Here's the best illustration I could find quickly of how your stuff would get drilled + riveted.

After that, illustrations of burn / melt hazards...

[Wheelman_13]

Cool. I have no issues drilling my tailpipe (already have honestly). My issue is that I think my the tips on the current tailpipes flare to like 3/3.5". Also good to know about the melting issues. I'd thought about that with the way the supertrapp works, but wasn't sure how real my concern was. Good information.

My "issue" illustrated below.


This is what the whole tailpipe system looks like...when new (minus swag purple tips )



So unfortunately lots of bends and crazy tip flares. As much as I like the noise it makes, I need it to make that noise, but at like 15-20DB less volume.

[MikeKelly]

I think you're in pretty good shape.

Advance, AutoZone and O'Reilly all carry (at least some of) the sort of stuff you need - I just saw 3" x __ reducers (several) at Advance a few minutes ago, but didn't look at them closely because I hadn't seen your post yet...


Sooo...

What you need is something in a 3" reducer that will fit either the inside or outside diameter of your exhaust tips (snug, we'll put a rivet or two through it), and the other end needs to say 2.5" (we can work with the I.D. or O.D. part) - but you're going to have to go test fit the 3" end...

You'll need to pay attention to the (3") I.D. or O.D. part.


BE SURE THAT GETS YOU WELL CLEAR OF MELTING THE BODY - or figure if we need to add another fitting of some sort to get clear.


Here's a link to a few Summit examples / part numbers:

https://www.summitracing.com/search/bra ... =Ascending




P.S. - we're not going to get 20db out of this, or at least I seriously doubt it...

Maybe ~8

[Wheelman_13]

Welp, I'll see if I get things together in time for this weekend. If not, then later in the season. Worst case I may just come hang out, lol. Too many projects to finish at once being back in town, selling a house in CO and looking for (a bigger one) here.

[MARKP]

After looking at your exhaust setup, I wonder if this would work for you.
http://www.dynomax.com/mufflers/ultra-f ... x-mufflers

[MikeKelly]

I suspect he won't get much out of that... (I could be wrong)

FEATURES & BENEFITS
Designed for vehicles with limited space
100-percent Welded design for maximum durability
Dyno proven to flow up to 2,000 SCFM and support up to 2,000 horsepower
Straight-through design ensures unrestricted exhaust flow and reduces back pressure
CRF Technology absorbs unwanted interior resonance while maintaining a deep performance tone

[MARKP]

We'll see. I'm putting an Ultra Flo on the Camaro.

Sent from my SPH-L710 using Tapatalk

[steverife]

The Ultra Flo is very effective on the applications that I've researched. Several small displacement screamer national level P and M cars run them and stay under about 94 db.

I think the downside is that they aren't the lightest.

[Wheelman_13]

Yeah, if I'm going to go "plan X" and just replace the tailpipe with something quieter, then I'll just spend the money on something with a couple of larger mufflers or similar, polish mine up and sell it to someone who wants something loud.

[MikeKelly]

You'll need to pay attention to the (3") I.D. or O.D. part.

One more size to try - if you find that you can't fit 3" I.D. or O.D. to your exhaust tips:


Try 2-3/4" I.D.