---------------------------------------------------------- RV8-List Digest Archive --- Total Messages Posted Thu 05/11/06: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:02 AM - Prop extensions versus prop weight and Acrobatics (Robert Sultzbach) 2. 08:17 AM - Re: Prop extensions versus prop weight and Acrobatics (LessDragProd@aol.com) 3. 10:13 AM - Re: Prop extensions versus prop weight and Acrobatics (Robert Sultzbach) ________________________________ Message 1 _____________________________________ Time: 07:02:57 AM PST US From: Robert Sultzbach Subject: RV8-List: Prop extensions versus prop weight and Acrobatics --> RV8-List message posted by: Robert Sultzbach Hi Bill, I too will be running a Sam James cowl on my 8A. I have chosen an ACI prop which is composite for those unaware of them. With all the back and forth going on on this board about prop extensions I decided to call the prop designer about any problems I might encounter with acro and the engine crankshaft. He told me it was a non issue because of the lightness of the composite prop. He actually performed some engineering and calculated some of the stresses out for me as we spoke. He said it was not a factor using the ACI prop which is 17 lbs. lighter than the Hartzell. He did mention the heavier metal prop could become problematic with an extension vis a vis acro but did not run any calculations. The moral of the story is the guys with light composite props probably don't have to worry about their prop extensions. Fly safely, Bob Sultzbach --- Bill Anton wrote: > --> RV8-List message posted by: "Bill Anton" > > > I'm close to finishing my RV-8 and have chosen to > install the SJ cowl, > plenum, and wheel pants. I am using the 200hp > Lycoming IO360 A1B6 in > conjunction with the Whirlwind 200RV prop. The first > -8 cowl was received 6 > months ago and we've just begun the installation. > The cowl will not work > without a prop extension without extensive > fiberglass work. Will James > directed me to a company called Sabre Manufacturing > that machines a very > beautiful prop extension. In speaking with the > owner, he assures me that > there will be no prop restrictions with the use of > this extension and that > they have never had a problem with this. I have > heard that the heavier > Hartzell CS prop could have some restriction with an > extension. You should > check with Sabre Mfg for their input. > > The original cowling would not fit the engine and > Will James is in the > process of redesigning the cowling to fit the RV-8 > with the 200hp lyc. He > has changed the design, including materials used, to > create a lighter and > stronger cowling than previously offered. The > plenum with baffling has been > installed and looks great. At this point I can't > answer any of the > questions regarding increased speed etc. I chose > the SJ products because I > like the appearance and wanted something a little > different. Hopefully, > there will be some speed and/or economy benefits. > It will be difficult to > quantify without apple to apple comparisons which > are hard to come by with > all the different ways the RVs are built. > > Bill > > -----Original Message----- > From: owner-rv8-list-server@matronics.com > [mailto:owner-rv8-list-server@matronics.com] On > Behalf Of RV8-List Digest > Server > Sent: Wednesday, May 10, 2006 1:58 AM > To: RV8-List Digest List > Subject: RV8-List Digest: 1 Msgs - 05/09/06 > > * > > ================================================== > Online Versions of Today's List Digest Archive > ================================================== > > Today's complete RV8-List Digest can also be found > in either of the > two Web Links listed below. The .html file includes > the Digest formatted > in HTML for viewing with a web browser and features > Hyperlinked Indexes > and Message Navigation. The .txt file includes the > plain ASCII version > of the RV8-List Digest and can be viewed with a > generic text editor > such as Notepad or with a web browser. > > HTML Version: > > > http://www.matronics.com/digest/rv8-list/Digest.RV8-List.2006-05-09.html > > Text Version: > > > http://www.matronics.com/digest/rv8-list/Digest.RV8-List.2006-05-09.txt > > > ================================================ > EMail Version of Today's List Digest Archive > ================================================ > > > > ---------------------------------------------------------- > RV8-List Digest Archive > --- > Total Messages Posted Tue > 05/09/06: 1 > > ---------------------------------------------------------- > > > Today's Message Index: > ---------------------- > > 1. 03:54 AM - James Cowl (Glen Matejcek) > > > > ________________________________ Message 1 > _____________________________________ > > > Time: 03:54:55 AM PST US > From: "Glen Matejcek" > Subject: RV8-List: James Cowl > > --> RV8-List message posted by: "Glen Matejcek" > > > Hi All- > > One thing that I haven't seen mentioned is the > effect an SJ cowl has on > acro. Recall the cracking issues around the > lightening holes in the Lyc > crank prop flanges when those cranks were used in > hard acro. A prop > extension will only make that tendency worse. While > I'm sure nobody is > actually going to do hard acro in an RV, a heavy CS > prop on the end of an > extension might cause cracking over time with > 'light' acro, whatever that > is. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > browse > Subscriptions page, > FAQ, > > > Admin. > > > > > > > > > > > __________________________________________________ ________________________________ Message 2 _____________________________________ Time: 08:17:26 AM PST US From: LessDragProd@aol.com Subject: Re: RV8-List: Prop extensions versus prop weight and Acrobatics --> RV8-List message posted by: LessDragProd@aol.com There is the MT Propeller. It is a bolt on propeller and spinner assembly that matches the Sam James cowl. No prop extension required. No aerobatic restrictions. There is an option of counterweighted blades to protect your engine and propeller from overspeeding during "zero" G and vertical maneuvers. It is also less expensive than the AC propeller. Just make certain that you provide the correct cowl spacing. Van's cowl installs at about 1 1/2", and the Sam James cowl installs at about 3 7/8". Regards, Jim Ayers Custom Aircraft Propellers A division of Less Drag Products, Inc. - An MT Propeller distributor Certified propellers custom designed for the experimental. In a message dated 05/11/2006 7:05:37 AM Pacific Daylight Time, endspeed@YAHOO.COM writes: --> RV8-List message posted by: Robert Sultzbach Hi Bill, I too will be running a Sam James cowl on my 8A. I have chosen an ACI prop which is composite for those unaware of them. With all the back and forth going on on this board about prop extensions I decided to call the prop designer about any problems I might encounter with acro and the engine crankshaft. He told me it was a non issue because of the lightness of the composite prop. He actually performed some engineering and calculated some of the stresses out for me as we spoke. He said it was not a factor using the ACI prop which is 17 lbs. lighter than the Hartzell. He did mention the heavier metal prop could become problematic with an extension vis a vis acro but did not run any calculations. The moral of the story is the guys with light composite props probably don't have to worry about their prop extensions. Fly safely, Bob Sultzbach ________________________________ Message 3 _____________________________________ Time: 10:13:57 AM PST US From: Robert Sultzbach Subject: Re: RV8-List: Prop extensions versus prop weight and Acrobatics --> RV8-List message posted by: Robert Sultzbach Good Point about the no prop extension required. My ACI prop doesn't need an extension either however, to be honest it is an extended hub. It has to be to work with the Sam James Cowl. The distance required is a fixed distance for any Sam James cowl. You can get there with either a prop extension on a std prop hub or an extended hub. I hope this clarifies the last post. Bob --- LessDragProd@aol.com wrote: > --> RV8-List message posted by: LessDragProd@aol.com > > > There is the MT Propeller. It is a bolt on > propeller and spinner assembly > that matches the Sam James cowl. > No prop extension required. No aerobatic > restrictions. > There is an option of counterweighted blades to > protect your engine and > propeller from overspeeding during "zero" G and > vertical maneuvers. > It is also less expensive than the AC propeller. > > Just make certain that you provide the correct cowl > spacing. Van's cowl > installs at about 1 1/2", and the Sam James cowl > installs at about 3 7/8". > > Regards, > Jim Ayers > Custom Aircraft Propellers > A division of Less Drag Products, Inc. - An MT > Propeller distributor > Certified propellers custom designed for the > experimental. > > In a message dated 05/11/2006 7:05:37 AM Pacific > Daylight Time, > endspeed@YAHOO.COM writes: > > > --> RV8-List message posted by: Robert Sultzbach > > > Hi Bill, > > I too will be running a Sam James cowl on my 8A. I > have chosen an ACI prop which is composite for > those > unaware of them. With all the back and forth going > on > on this board about prop extensions I decided to > call > the prop designer about any problems I might > encounter > with acro and the engine crankshaft. He told me it > was a non issue because of the lightness of the > composite prop. He actually performed some > engineering and calculated some of the stresses out > for me as we spoke. He said it was not a factor > using > the ACI prop which is 17 lbs. lighter than the > Hartzell. He did mention the heavier metal prop > could > become problematic with an extension vis a vis acro > but did not run any calculations. The moral of the > story is the guys with light composite props > probably > don't have to worry about their prop extensions. > > Fly safely, > Bob Sultzbach > > > > > > > > > > browse > Subscriptions page, > FAQ, > > > Admin. > > > > > > > > > > > __________________________________________________