X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from elasmtp-kukur.atl.sa.earthlink.net ([209.86.89.65] verified) by logan.com (CommuniGate Pro SMTP 6.0.8) with ESMTP id 6687859 for lml@lancaironline.net; Wed, 15 Jan 2014 09:07:04 -0500 Received-SPF: none receiver=logan.com; client-ip=209.86.89.65; envelope-from=colyncase@earthlink.net DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=W64wSKbfYx59iyLu1HlXU5Gy55+iOdObGpCo1v8gLujOq1ICwN9Mlx3zjXgFkYkT; h=Received:From:Mime-Version:Content-Type:Subject:Date:In-Reply-To:To:References:Message-Id:X-Mailer:X-ELNK-Trace:X-Originating-IP; Received: from [64.223.93.133] (helo=[192.168.1.24]) by elasmtp-kukur.atl.sa.earthlink.net with esmtpa (Exim 4.67) (envelope-from ) id 1W3R6y-0005VX-3t for lml@lancaironline.net; Wed, 15 Jan 2014 09:06:28 -0500 From: Colyn Case Mime-Version: 1.0 (Apple Message framework v1085) Content-Type: multipart/alternative; boundary=Apple-Mail-308--829273184 Subject: Re: [LML] Re: Carburetor air intake filter Date: Wed, 15 Jan 2014 09:06:27 -0500 In-Reply-To: To: "Lancair Mailing List" References: Message-Id: <6A070D44-1EED-466E-BBCA-420BA5900311@earthlink.net> X-Mailer: Apple Mail (2.1085) X-ELNK-Trace: 63d5d3452847f8b1d6dd28457998182d7e972de0d01da940c98c4e37ccea0a0786f4b7feb17619c3350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 64.223.93.133 --Apple-Mail-308--829273184 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii I could get excited about better air filter efficiency if I could buy an = efficient oil filter for my aircraft engine. =20 On Jan 15, 2014, at 7:57 AM, Gary Casey wrote: There is always lots of discussion about air filters, and I believe you = can make a case for not using a filter at all. It depends on how much = ground running you expect to do and the atmospheric conditions. One = takeoff at a dry, dusty, windy airport might cause as much wear as 1,000 = hours of ingesting clean air. So, if you are willing to be cautious = about the conditions you fly in, I suppose that works. But most aren't willing to take the risk - I wasn't, anyway. But then I = see lots of comments (also among car enthusiasts) about K and N filters. = They are truly better - about advertising. Too bad their filters = aren't as good. I've tried to get information from them about = filtration efficiency and I've only got vague references to it being = "really good." Somewhere I have a technical paper that compares their = filter to typical paper filters. Theirs has a filtration efficiency, = when done according to SAE standards, of about 92 and maybe 94 percent. = That sounds pretty good in the ads - only 6 percent of the dirt gets = through - by weight. But most of the particles are small, so if you = want to count particles, a lot of them get through. By contrast, a = typical paper filter has an efficiency of about 99 percent or more. The = newer technology can be 99.7 percent efficient. So that says the K and = N filter passes at least 6 times and perhaps as much as 10 times as much = dust as a paper filter. And the paper filter isn't just "paper," it is = a very high-tech blend of natural and synthetic material. True, the = paper filter of the same volume will have more restriction - probably = twice as much. The power reduction might be something like 2 percent = with a paper filter and 1 percent with a K and N, but more like half = that if you oversize the filter a little. So, is the better filtration worth losing 1 hp in an O-360? For me, it = is. Gary Casey --Apple-Mail-308--829273184 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=us-ascii I = could get excited about better air filter efficiency if I could buy an = efficient oil filter for my aircraft engine.

On = Jan 15, 2014, at 7:57 AM, Gary Casey wrote:

There is = always lots of discussion about air filters, and I believe you can make = a case for not using a filter at all. It depends on how much = ground running you expect to do and the atmospheric conditions. = One takeoff at a dry, dusty, windy airport might cause as much = wear as 1,000 hours of ingesting clean air. So, if you are willing = to be cautious about the conditions you fly in, I suppose that = works.

But most aren't willing to take the risk - I wasn't, = anyway. But then I see lots of comments (also among car = enthusiasts) about K and N filters. They are truly better - about = advertising. Too bad their filters aren't as good. I've tried to get information from them about filtration = efficiency and I've only got vague references to it being "really good." = Somewhere I have a technical paper that compares their filter to = typical paper filters. Theirs has a filtration efficiency, when = done according to SAE standards, of about 92 and maybe 94 percent. = That sounds pretty good in the ads - only 6 percent of the dirt = gets through - by weight. But most of the particles are small, so = if you want to count particles, a lot of them get through. By = contrast, a typical paper filter has an efficiency of about 99 percent = or more. The newer technology can be 99.7 percent efficient. = So that says the K and N filter passes at least 6 times and = perhaps as much as 10 times as much dust as a paper filter. And = the paper filter isn't just "paper," it is a very high-tech blend of = natural and synthetic material. True, the paper filter of the same volume will have more restriction - probably twice = as much. The power reduction might be something like 2 percent = with a paper filter and 1 percent with a K and N, but more like half = that if you oversize the filter a little.

So, is the better filtration = worth losing 1 hp in an O-360? For me, it is.

Gary = Casey

= --Apple-Mail-308--829273184--