The Murphy Builders Site

Hello Group:
I am building a Rebel and eventually will be installing a Lycoming O320-E2D (160 HP), Murphy fiberglass speed cowl, Fife Tips and Murphy 1800 Amphib Floats. Installation of VG's will be entertained later.

Have searched the Rebel archives and SuperCub.org concerning performance and size information of a Borer Propeller with a similar setup as mine and came up with little information.

Rebel 662 is in progress and I have the opportunity to purchase a Borer Propeller locally. If the Borer is a viable prop to hang on the front end of a Rebel Amphib with my specifications, what would be the best size/pitch to purchase for optimum takeoff AND cruise (mid-range)? Also, what would be the length of the prop extension that would be required with the speed cowl and Borer?

Thank you in advance for any comments, ideas and suggestions on this subject.

Regards,
Terry R662

My Rebel on Murphy 1800 amphibs had great off the water performance with an O-320/160 hp and a Borer 81x42 (down from 82x42). Cruise was slow...2400 rpm giving about 85-90 mph. Walter Klatt is a strong proponent of the Sensenich 74x 54, which he has done head to head comparisons with various popular props before he upgraded to an O-360.
On wheels the Borer was seriously under pitched...take off in about 100 feet and real danger of overspeeding the engine if not careful.

Hope that's some use to you.

John
C-FRGV

Oh, and...

In my mind, the only reason not to go straight to VGs is so you can see the very significant improvement in handling and performance when you do add them. Profound improvement in slow speed handling and the plane no longer really stalls,it just mushes down.

John

Thank you John for the information on your Borer. Confirms my suspicions that with little archive information and your information, a Borer prop just is not suited for my O320-E2D Rebel on amphibs mission.

Hey, Terry, get yourself a metal 2 blade Sensenich 74 X 54 (not 56, even for the 160hp). It is the best prop for the 320 Rebel amphib. It is great off the water, good climb, and good cruise. All the others I have tested have too much of a compromise, and not good in at least one of those three.

Hello Walter:

Thank you for your reply. Initially, I had my sights on a “good deal” on a Borer, but now, with information in hand, that has been shelved. The two-blade Sensenich 74 x 54 sounds exactly what I am looking for. Knowing that you have accomplished a lot of testing with different props, your knowledgeable suggestion is duly noted. For now, I will continue my build on R662 and the quest for a Sensenich.

Thank you all for the valuable information!

Regards,
Terry R662