---------------------------------------------------------- Pietenpol-List Digest Archive --- Total Messages Posted Wed 07/18/18: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:29 PM - Re: Ford Crankshaft Choice (taildrags) 2. 02:04 PM - Re: Re: Ford Crankshaft Choice (Glen Schweizer) 3. 02:43 PM - Re: Re: Ford Crankshaft Choice (John C Black) 4. 09:55 PM - Re: Ford Crankshaft Choice (taildrags) ________________________________ Message 1 _____________________________________ Time: 01:29:37 PM PST US Subject: Pietenpol-List: Re: Ford Crankshaft Choice From: "taildrags" John; I'm really surprised that no one has replied to your query about the crank, since there are quite a number of those engines out there and plenty of hands-on engine rebuilders too. I know Ernie Moreno up here in Independence is building up a Ford to put on his Piet to replace the Franklin that he's got on it now. The extra weight up front will help Ernie's airplane with tail-heaviness. -------- Oscar Zuniga Medford, OR Air Camper NX41CC "Scout" A75 power, 72x36 Culver prop Read this topic online here: http://forums.matronics.com/viewtopic.php?p=481734#481734 ________________________________ Message 2 _____________________________________ Time: 02:04:27 PM PST US From: Glen Schweizer Subject: Re: Pietenpol-List: Re: Ford Crankshaft Choice Ernies at Oshkosh > On Jul 18, 2018, at 1:29 PM, taildrags wrote: > > > John; I'm really surprised that no one has replied to your query about the crank, since there are quite a number of those engines out there and plenty of hands-on engine rebuilders too. I know Ernie Moreno up here in Independence is building up a Ford to put on his Piet to replace the Franklin that he's got on it now. The extra weight up front will help Ernie's airplane with tail-heaviness. > > -------- > Oscar Zuniga > Medford, OR > Air Camper NX41CC "Scout" > A75 power, 72x36 Culver prop > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=481734#481734 > > > > > > > > > ________________________________ Message 3 _____________________________________ Time: 02:43:48 PM PST US From: John C Black Subject: Re: Pietenpol-List: Re: Ford Crankshaft Choice I have heard from 2 guys off list. I learned that using a 76x44 prop or a 78x42 prop. Model A engine turns 2100 RPM on takeoff, cruises at 1700-1800 RPM, probably never exceeds 2200 RPM. I took my model A Ford car (pic Below) out and ran the engine at 1700-2200 RPM and drove at those RPMs. The Model A engine in the car has no counterweights on the crank. The engine has been balanced. I did not experience any harmonic vibration. My rearview mirror amplifies the vibration and serves as a great observable indicator. Based on this test, I am leaning toward using the 1932 Model B crank without counterweights. I figure saving 12-14 pounds is a big deal. John On Jul 18, 2018, at 1:29 PM, taildrags wrote: John; I'm really surprised that no one has replied to your query about the crank, since there are quite a number of those engines out there and plenty of hands-on engine rebuilders too. I know Ernie Moreno up here in Independence is building up a Ford to put on his Piet to replace the Franklin that he's got on it now. The extra weight up front will help Ernie's airplane with tail-heaviness. -------- Oscar Zuniga Medford, OR Air Camper NX41CC "Scout" A75 power, 72x36 Culver prop Read this topic online here: http://forums.matronics.com/viewtopic.php?p=481734#481734 ________________________________ Message 4 _____________________________________ Time: 09:55:57 PM PST US Subject: Pietenpol-List: Re: Ford Crankshaft Choice From: "taildrags" John; in the larger scheme of things, saving 12-14 lbs is certainly worth pursuing since lower gross weight means reduced lift required to climb, and thus reduced engine thrust to produce the lift. However, many Piets end up tail heavy and have to shift weight forward somehow, or else shift the wing aft to adjust the CG. Additional weight up near the prop can help balance the airplane. It sounds like you're performing your due diligence in making the decision on which way to go on the crank though. -------- Oscar Zuniga Medford, OR Air Camper NX41CC "Scout" A75 power, 72x36 Culver prop Read this topic online here: http://forums.matronics.com/viewtopic.php?p=481744#481744 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message pietenpol-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Pietenpol-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/pietenpol-list Browse Digests http://www.matronics.com/digest/pietenpol-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.