X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-ob0-f181.google.com ([209.85.214.181] verified) by logan.com (CommuniGate Pro SMTP 6.0.8) with ESMTPS id 6735390 for flyrotary@lancaironline.net; Sun, 16 Feb 2014 17:25:14 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.214.181; envelope-from=msteitle@gmail.com Received: by mail-ob0-f181.google.com with SMTP id va2so15804831obc.26 for ; Sun, 16 Feb 2014 14:24:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:references:from:content-type:in-reply-to:message-id:date:to :content-transfer-encoding:mime-version; bh=yZB2/M64MViKCrQ8a4Nx091XCO3cdkK97uqyV4KWB74=; b=YqkMbQuZZDn+F/RN8GFMZtGCsf2p32hv/l5CEf1X2DDgHOMdJbEzXeKlssXgD5UGLP FbgR9vYM6Ag3Uk0zzdl7gFCkFjlC919xgFPDTh8tWInRovnBxhqBQ0EapE77h1klgRqJ oULAhFeIuNAANOLp116N1Gq8kQukzJKMTfZcC1Wjdw+cQUb30oKp6OFBcXlcUuvfMpY3 BuUYIIdAtyJqH6xBmhC7K3G+Ov0pgds22mB5TBV+/0Z2VNdikhENyN1pzH1BS87OG+z1 D3Y4S+tOG7NyIkTH1F9rpG7UqS9gNjHKL24pNpU+kEzpuN8HKl6XV9ALQre6YhQ86dNZ 8Ojg== X-Received: by 10.60.63.242 with SMTP id j18mr17995247oes.33.1392589481890; Sun, 16 Feb 2014 14:24:41 -0800 (PST) Return-Path: Received: from [192.168.1.102] (cpe-173-172-120-114.austin.res.rr.com. [173.172.120.114]) by mx.google.com with ESMTPSA id qh4sm40834244obc.4.2014.02.16.14.24.41 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sun, 16 Feb 2014 14:24:41 -0800 (PST) Subject: Re: [FlyRotary] Sound Level Testing References: From: Mark Steitle Content-Type: multipart/alternative; boundary=Apple-Mail-A5B79042-DE72-412E-B549-B488789AB07D X-Mailer: iPad Mail (11B554a) In-Reply-To: Message-Id: Date: Sun, 16 Feb 2014 16:24:40 -0600 To: Rotary motors in aircraft Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (1.0) --Apple-Mail-A5B79042-DE72-412E-B549-B488789AB07D Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Anxious to hear how well it does. I'm planning a similar system for my 3-ro= tor. =20 Mark Sent from my iPad > On Feb 16, 2014, at 4:09 PM, shipchief@aol.com wrote: >=20 > I bought a Wensn 30-130 Decibel sound meter off fleabay. I use it to recor= d sound levels in front of my face in flight. > I first tested my RV-8 after installing a turn down tip, but was also exp= eriencing severe exhaust leaks from my turbo: 19.7 DBa=20 > After fixing the leak, I recorded 16.8 DBa > Then I squeezed the turn down tip to a flattened rectangle opening, and re= placed the lost area with 1/4" holes, which I bent to face backwards with a P= hilips screwdriver. a Piccolo Pipe, as it's known. Kind of a cheese grater f= or sound waves. Next reading: 14.6 DBa > This is still to loud for my worn out ears, so I bought an Aeroturbine 252= 5 muffler, as described on this forum. I've been collecting 304 stainless pi= pe bend, ball joints clamps and hangers. I hope to get something cobbled tog= ether this weekend. > I have a 2" exhaust pipe from the turbo which discharges aft. The pipe has= 2 90 degree bends and exhausts in and parallel to the exit air ramp on the b= ottom. I plan to use the Ford type exhaust hangers with 3/8" rods. --Apple-Mail-A5B79042-DE72-412E-B549-B488789AB07D Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 7bit

Anxious to hear how well it does. I'm planning a similar system for my 3-rotor.

Mark

Sent from my iPad

On Feb 16, 2014, at 4:09 PM, shipchief@aol.com wrote:

I bought a Wensn 30-130 Decibel sound meter off fleabay. I use it to record sound levels in front of my face in flight.

I first tested my RV-8 after installing a turn down tip, but was also experiencing severe exhaust leaks from my turbo: 19.7 DBa

After fixing the leak, I recorded 16.8 DBa

Then I squeezed the turn down tip to a flattened rectangle opening, and replaced the lost area with 1/4" holes, which I bent to face backwards with a Philips screwdriver. a Piccolo Pipe, as it's known. Kind of a cheese grater for sound waves. Next reading: 14.6 DBa

This is still to loud for my worn out ears, so I bought an Aeroturbine 2525 muffler, as described on this forum. I've been collecting 304 stainless pipe bend, ball joints clamps and hangers. I hope to get something cobbled together this weekend.

I have a 2" exhaust pipe from the turbo which discharges aft. The pipe has 2 90 degree bends and exhausts in and parallel to the exit air ramp on the bottom. I plan to use the Ford type exhaust hangers with 3/8" rods.

--Apple-Mail-A5B79042-DE72-412E-B549-B488789AB07D--