X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mx2.netapp.com ([216.240.18.37] verified) by logan.com (CommuniGate Pro SMTP 5.3.7) with ESMTPS id 4312615 for flyrotary@lancaironline.net; Wed, 12 May 2010 21:29:45 -0400 Received-SPF: softfail receiver=logan.com; client-ip=216.240.18.37; envelope-from=echristley@nc.rr.com X-IronPort-AV: E=Sophos;i="4.53,218,1272870000"; d="scan'208";a="359068458" Received: from smtp1.corp.netapp.com ([10.57.156.124]) by mx2-out.netapp.com with ESMTP; 12 May 2010 18:28:38 -0700 Received: from [10.30.20.172] (mhe01-lxp.hq.netapp.com [10.30.20.172] (may be forged)) by smtp1.corp.netapp.com (8.13.1/8.13.1/NTAP-1.6) with ESMTP id o4D1Sb1O022087 for ; Wed, 12 May 2010 18:28:38 -0700 (PDT) Message-ID: <4BEB55C5.80009@nc.rr.com> Date: Wed, 12 May 2010 21:28:37 -0400 From: Ernest Christley Reply-To: echristley@nc.rr.com User-Agent: Thunderbird 2.0.0.24 (X11/20100317) MIME-Version: 1.0 To: Rotary motors in aircraft Subject: Re: [FlyRotary] Re: alternative water pump References: In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit George Lendich wrote: > Bill, > Point taken! > I hope the 16X is better. Can't understand why Mazda would make such > a shitty impeller for what appears to be a well thought out , > lightened water pump. > George Because it is much, MUCH cheaper, and will at most drop the efficiency of the pump from 90% to 85% at most? (yeah, I made those numbers up, but it will be somewhere in the ballpark.) If they were concerned about more flow, they would just make the cheaper impeller a mm larger in diameter. Or maybe they looked at failed units and saw that they all died of bearing failure, and none died from cavitation erosion of the impeller? They are, after all, in business to make money, not to please a certain aesthetic with no engineering basis.