Return-Path: Received: from wb1-a.mail.utexas.edu ([128.83.126.134] verified) by logan.com (CommuniGate Pro SMTP 4.2b2) with ESMTP-TLS id 3210423 for flyrotary@lancaironline.net; Fri, 07 May 2004 09:47:37 -0400 Received: (qmail 82522 invoked from network); 7 May 2004 13:47:36 -0000 Received: from dhcp-191-101.per.utexas.edu (HELO benefits3.mail.utexas.edu) (146.6.191.101) by wb1.mail.utexas.edu with RC4-SHA encrypted SMTP; 7 May 2004 13:47:36 -0000 Message-Id: <5.1.1.5.2.20040507083649.02266c30@localhost> X-Sender: msteitle@mail.utexas.edu@localhost X-Mailer: QUALCOMM Windows Eudora Version 5.1.1 Date: Fri, 07 May 2004 08:46:54 -0500 To: "Rotary motors in aircraft" From: Mark Steitle Subject: Re: [FlyRotary] Re: E-shaft pulley diameters In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed Now this is beginning to make sense to me. The stock 20B e-shaft pulley is 5.5", and the wp pulley is 4". I guess Mazda did this in the Cosmo since it was a luxury car (with an automatic trans) and not subject to as high of rpms as the RX-7's. Another probability is that the Cosmo's electrical demands were greater, and therefore required the alternators to be spun faster. I need to find (or build) a 4" multi-V e-shaft pulley, or change everything to a dual V-type so I can use undersize after-market pulleys. Mark S. At 06:32 AM 5/7/2004 +0000, you wrote: > Mike, > > The Racing Beat and MazdaTrix dual V-belt undersize pulley is > 3-7/8" diameter. The same as the stock 86-91 waterpump pulley. > > Kelly Troyer > >-- >Dyke Delta/13B Rotary Power > > > > > > > > I was browsing Racing Beat and MazdaTrix looking at the undersized > > pulleys. They don't list the actual size of the pulley, Racing Beat says > > underdriven 13-15%. Comparing my 4.5" pulley that would make it about > > 3-7/8" diameter. Does that sound about right? Does anyone have a > > measurement of the diameter of these? > > > > Thanks, > > Mike > > > > Mike McGee, RV-4 N996RV, O320-E2G, Hillsboro, OR > > 13B in gestation mode, RD-1C, EC-2 > > > > > > > > >> Homepage: http://www.flyrotary.com/ > > >> Archive: http://lancaironline.net/lists/flyrotary/List.html > > >> Homepage: http://www.flyrotary.com/ > >> Archive: http://lancaironline.net/lists/flyrotary/List.html