X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.121] verified) by logan.com (CommuniGate Pro SMTP 5.2c4) with ESMTP id 2636959 for flyrotary@lancaironline.net; Tue, 08 Jan 2008 21:37:36 -0500 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.121; envelope-from=eanderson@carolina.rr.com Received: from edward2 ([24.74.103.61]) by cdptpa-omta06.mail.rr.com with SMTP id <20080109023657.PEOO26668.cdptpa-omta06.mail.rr.com@edward2> for ; Wed, 9 Jan 2008 02:36:57 +0000 Message-ID: <000701c85268$8a7fd910$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Dennis' Muffler Date: Tue, 8 Jan 2008 21:37:13 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0004_01C8523E.A17098A0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3138 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3138 This is a multi-part message in MIME format. ------=_NextPart_000_0004_01C8523E.A17098A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Bill, I have two of the larger Hushpower II mufflers (twice the length = of the resonator). My turbo 13B block without a turbocharger (and no = exhaust splitters) is indeed the 13B with the steroid pumped exhaust = sound. It has been measure at 125DB (pre muffler) and it may well have = been higher - but that was the top of the meter's DB scale. It was not = loud, it was ear shattering! However, the Renesis has a much less aggressive bark and is therefore = easier to quite. So a resonator alone may indeed be more effective on = the Renesis than the full muffler on my turbo block 13B. Actually, mine would sound a bit less noisy with only 1 hushpowerII (due = to the acoustical physics of sound dampening) - but it was going to cost = me over $400 to have my two-pipe header redone into a single header = enabling me to use one muffler. But at $100 each, two of the mufflers = were cheaper (if not lighter nor quite as effective), so I went that = route. Ed ----- Original Message -----=20 From: Bill Bradburry=20 To: Rotary motors in aircraft=20 Sent: Tuesday, January 08, 2008 8:38 PM Subject: [FlyRotary] Re: Dennis' Muffler Has anybody weighed one of these resonators? =20 =20 Ed, do you have one of these on your plane? Is the difference in = sound levels of yours and Dennis' plane due to the differences in the = 13b and the Renesis? =20 Bill B=20 =20 -------------------------------------------------------------------------= ----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of Ed Anderson Sent: Tuesday, January 08, 2008 7:49 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Dennis' Muffler No Packing, Kelly. Basically concentric tubes with holes in them. It = appears to use acoustical wave damping as a primary sound suppression = technique followed by damping from the energy lost caused by the = numerous holes. The HushPower resonator is basically 1/2 of the = regular HushPower II muffler (also 1/2 its length) =20 Ed ----- Original Message -----=20 From: Kelly Troyer=20 To: Rotary motors in aircraft=20 Sent: Tuesday, January 08, 2008 6:47 PM Subject: [FlyRotary] Re: Dennis' Muffler =20 Mark, Any info on what the packing is in the "Hushpower"?? =20 Thanks -- Kelly Troyer=20 "Dyke Delta"_13B ROTARY Engine=20 "RWS"_RD1C/EC2/EM2=20 "Mistral"_Backplate/Oil Manifold=20 =20 -------------- Original message from "Mark Steitle" = : --------------=20 Bill,=20 Here is a cutaway of the Hushpower II Resonator. I'll have to get = the dimensions this weekend. The dimensions you quoted are pretty = close, but you may need a heat shield, or some Zetex to protect the = fiberglass. =20 Mark ------=_NextPart_000_0004_01C8523E.A17098A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Bill, I have two of the larger Hushpower II = mufflers=20 (twice the length of the resonator).  My turbo 13B block without a=20 turbocharger (and no exhaust splitters)  is indeed the 13B with the = steroid=20 pumped exhaust sound.  It has been measure at 125DB (pre muffler) = and it=20 may well have been higher - but that was the top of the meter's DB = scale. =20 It was not loud, it was ear shattering!
 
However, the Renesis has a much less aggressive = bark and=20 is therefore easier to quite.  So a resonator alone may indeed be = more=20 effective on the Renesis than the full muffler on my turbo block=20 13B.
 
Actually, mine would sound a bit less noisy with = only 1=20 hushpowerII (due to the acoustical physics of sound dampening) - but it = was=20 going to cost me over $400 to have my two-pipe header redone into a = single=20 header enabling me to use one muffler.  But at $100 each, two of = the=20 mufflers were cheaper (if not lighter nor quite as effective), so I went = that=20 route.
 
Ed
 
----- Original Message -----
From:=20 Bill=20 Bradburry
Sent: Tuesday, January 08, 2008 = 8:38=20 PM
Subject: [FlyRotary] Re: = Dennis'=20 Muffler

Has anybody weighed one of these = resonators? =20

 

Ed, do you have one of these on your = plane?  Is=20 the difference in sound levels of yours and Dennis=92 plane due to the = differences in the 13b and the Renesis?

 

Bill = B 

 

From:=20 Rotary motors in aircraft = [mailto:flyrotary@lancaironline.net] On=20 Behalf Of Ed Anderson
Sent: Tuesday, January 08, 2008 = 7:49=20 PM
To: = Rotary motors in aircraft
Subject: [FlyRotary] Re: = Dennis'=20 Muffler

No Packing, Kelly.  = Basically=20 concentric tubes with holes in them.  It appears to use = acoustical wave=20 damping as a primary sound suppression technique followed by = damping from=20 the energy lost caused by  the numerous holes.  The = HushPower=20  resonator is basically 1/2 of the regular HushPower II muffler = (also 1/2=20 its length)

 

Ed

----- Original Message = -----=20

From: Kelly = Troyer=20

To: Rotary motors in = aircraft=20

Sent:=20 Tuesday, January 08, 2008 6:47 PM

Subject:=20 [FlyRotary] Re: Dennis' Muffler

 

 =20 Mark,

    Any info on what the = packing is=20 in the "Hushpower"??

 

Thanks

--
Kelly Troyer =
"Dyke Delta"_13B=20 ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil = Manifold=20


 

--------------=20 Original message from "Mark Steitle" <msteitle@gmail.com>:=20 --------------

Bill,

Here is a cutaway of the = Hushpower II=20 Resonator.  I'll have to get the dimensions this = weekend.  The=20 dimensions you quoted are pretty close, but you may need a heat = shield, or=20 some Zetex to protect the fiberglass. =20 =

Mark

= ------=_NextPart_000_0004_01C8523E.A17098A0--