Hushpower (Flowmaster) DBX Mufflers
 

I was on my second rattley stock muffler and was looking for something with a little more aggressive sound. These look like straight through mufflers but actually are not. They do employ some noise canceling technology. They are currently available only direct from Flowmaster by special order. Just finished installing a pair yesterday and I am very happy with the result. Barely noticeable at idle but a deep growl when accelerating and a pleasant bass burble when letting off the throttle. Noise level at cruising speed is louder than stock but no annoying drone.

http://986forum.com/forums/attachmen...id=12768&stc=1

a sound clip at idle and drive by would be nice if you can get one.

What did you pay for it?

I paid $250 for the mufflers plus shipping, about $75 for tips, clamps, bends and bar stock, and $30 to have it welded. I did all the measuring, cutting, bending, fitting and tack welding myself.

I'll see if I can get a sound clip.

Hushpowers
 

Glad to hear you like our mufflers. I work for Flowmaster/Hushpower. These are very unique mufflers with patented design and cool exterior temps. We recently put a set on a GTP Spice race car to meet sounds requirements for Infineon Raceway. With no loss of power. Check them out online at www.hushpower.com. Glad you like them. Love the creativity.

Flowmann, your company should make these for boxsters. All the aftermarket ones we've used on this forum, including me, are "prone to drone" and the cabin resonance is deafening if you're caught in the rain in the city and you have to have the top up and you're forced to drive in the 2-3k rpm range.

I'd be happy to work with you on a prototype :)

I'd like to hear that and the "hushpower" as well!
:cheers:

Looks like a trick set-up! Love hear the sound... :cheers:

wow
 

That looks great. I'm with the others, I wanna hear these things in action, and I kinda :eek:-ed at what you paid for them. That just makes it even more awesome. :cheers:

I see a stellar business opportunity here for the enterprising hobby welder. I'd buy one of these in a heartbeat if someone would make one for me and the price wasn't outrageous.

I'm serious. I'd even pay someone the materials cost up front to eliminate the financial risk.

I can just about +1 you there, Randall. Those things look great, and that's one hell of a DIY job he did. Really wanna hear how it turned out.

If I had a little more confidence in my cheap wirefeed welder I'd be tempted. It was a fun project and not really that difficult.

I took a stab at a sound clip with my phone but can't figure out out to upload the darned file. I'll try again with my Ipod.

After having driven in the rain for a couple days with the top up, I can't honestly say there is zero drone. There is a resonance with throttle around 2200-2600 rpm. With the top down it doesn't seem like much more than a hum.

That said, I love the sound this setup makes tooling around town.

The fact that the cabin resonance is more of a "hum" compared to a deafening drone is great to hear.

Figure out how to email yourself the audio file from your phone and then upload it to the site or email it to me and I'll post it on the web for you and give you a link to use. PM me for my email address.

BTW guys, I have PM'd Flowmann and asked him to talk to the powers that be at Flowmaster about making up some of these units.

I will say this about sound clips of exhaust notes on the internet... they just don't do a good or bad muffler justice. Even a CGT doesn't sound all that great over computer speakers... if you're standing next to one or riding in one, you get the feeling of it deep in your chest though :)

I'm inclined to figure out how to get this setup for myself one way or another even if I've never heard it... just the lack of cabin resonance I have now would be a vast improvement.

One thing that bothers me a little about this setup is that the two exhaust streams don't meet, so you effectively have two, separate, 3-cylinder exhaust paths without the benefit of a "balance tube" between them.

As I understand it (and I confess that I do not have a degree in fluid dynamics like my friend Mike, who has parlayed said degree into a quality-control job at Sam Adams Brewery, lucky bastard), most engines benefit from the exhaust scavenging that results from a balance tube.

Just a thought, and intended only as constructive criticism. Kudos to the OP for trying something different, though. :cheers:

Boxster exhausts don't utilize a true crossover. From what I've read, the merge/crossover needs to be before the mufflers to be effective, and as colse to the headers as possible. The Boxster just dumps both banks into a common muffler chamber, or in the case of the 987, they join after the mufflers.

How does the weight compare to the OEM muffler?

Ok, I recorded some clips with my Ipod and posted on Youtube. The first is idling and reving a bit. The second is a drive around the block. The third is a driveby. Meanwhile Flowmaster has asked me for a couple photos and a blurb for their website. Maybe I can get a free t-shirt or something. :cool:

http://www.youtube.com/watch?v=syw_GuUAR5c
http://www.youtube.com/watch?v=m--LAZ1DYoA
http://www.youtube.com/watch?v=m--LAZ1DYoA

Actually, the 2nd and 3rd links are the same one.

This is the third one: http://www.youtube.com/watch?v=c6U9NQJcnus

Well, I know vids/sound clips don't give us a 100% idea, but it's better than leaving it to my imagination. I have to say from what I heard of your little cruise around the block, those sound pretty nice. Like you said, a little loud when they need to be, but not ridiculous.

Now take a passenger with you so we can hear a little highway cruising. :p

Thanks Stroked & Blown.

As I get used to it, I like it more and more. Here's a pic all cleaned up.

Woah! an 8 wheeled Boxster!
That mush corner like a dream.

S&B, that's funny! :dance:

Here's something I've been thinking about. What if the two mufflers were connected with sheet metal making a continuous cylinder? Could the space in between the mufflers (8 inches or so) be used as sort of a balance chamber? Would there be any advantage in performance or sound level? I’m using layout “A”. The exhaust streams could be mixed in the center chamber either by deleting the internal tubes entirely or perforating them. Maybe someone from Flowmaster is following along could give us an opinion on this.

Wret was nice enough to let me come check out his muffler set up today. It is a VERY nice sysytem. Really clean with quality workmanship and it sounds great, closer to a 987 but alittle louder. We didn't have time to take a ride in it but when he revved the engine it had a nice growl. Overall, a quality muffler that is as good if not better than most aftermarket systems on the market today.

Any time JTP. Let me know if you want to take it for a spin. By the way, here's a parts list if anyone wants to put one of these together.

Hushpower DBX mufflers 2” inlet/outlet (2). Special Order by phone from Flowmaster. At the time I ordered, 2” ID was the smallest diameter available. This requires shims to get down to the 1 ¾ inlet pipe. Call 877-394-2878 ext 716 for more info.

3” Stainless tips, 2” inlet. Max 6” length. A 6” tip will protrude about an inch more than the stock tips, which to me was not an issue. If you want to keep the tips tucked as far under as stock, you will need to find a shorter tip. I bought these from Summit but you may be able to get them direct from Flowmaster.
http://www.summitracing.com/parts/FLO-15360/

2” 90° bends with 2” radius (2) Don’t get a larger radius or they won’t fit.
http://cgi.ebay.com/ebaymotors/2-mandrel-90-degree-bend-304-stainless-/270600943010?cmd=ViewItem&pt=Motors_Car_Truck_Part s_Accessories&hash=item3f0112b5a2

2” 90° bend with longer legs. The bends above have very short legs with very little excess material. Some 2” straight pipe is necessary for shim stock (only really need about 6”). This one comes from Jegs and may get you a free hat. 
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=200474206900&ssPageNam e=STRK:MEWAX:IT

Stainless steel bar stock 1” x 1/8” x 36” (min)
http://cgi.ebay.com/1-8-x-1-Stainless-Steel-304-304L-Flat-Strip-Bar-48-/180360116257?cmd=ViewItem&pt=LH_DefaultDomain_0&ha sh=%257B%2522Page%2522%253A%2522%252FMetals-Alloys-%252F29402%252Fi.html%253F_nkw%253Dstainless%25252 01%252522%2526_trkparms%253D65%2525253A12%2525257C 66%2525253A2%2525257C39%2525253A3%2525257C72%25252 53A3018%2526_trksid%253Dp3286.c0.m14.l1513%2526_pg n%253D3%2526hash%253Ditem29fe4cf821%2522%257D

2.25” muffler clamps (2) preferably stainless steel
http://www.summitracing.com/parts/SUM-694722/

Replacement bolts and nuts for clamps between the cats and mufflers (2) preferably stainless steel. M8 x 50mm (or longer). The bolts will likely be unusable after removal and may need to be cut.

M8 x 30mm (or longer) stainless bolts for hangers (2).

I don't believe you'll see any performance gain by connecting the two mufflers, though you should be able to change the sound a bit. Without baffles or packing you probably won't lessen the sound though.

Wret,

how does the weight compare to the stock unit?

Michael

Reviving an old thread. To the OP, do you have any pics of the setup?