tIANci

Prop - APC 9x8
Fuel - 5% Cool Power
Misc - quiet muffler no baffle
Tach - 16,000 RPM

Prop - APC 10x8
Fuel - 5% Cool Power
Misc - quiet muffler no baffle
Tach - 13,800 RPM

Throttle response is so crisp, this motor beats a TT46 or the 46AX any day but costs less.

asmund

Here`s another one: 13700 rpm on apc 12.25-3.75, fitted with a tower tuned muffler

Eganwp

My Feedback: (1)

My Testing Results

5% Omega; 12*C; 2% added castor oil, after 10 tanks break-in, wood bench tests; stock head shims in place; OS #8; sealed engine

Stock Muffler:
Prop, RPM, Thrust (lbs), Speed (n.mph), HP
MAS 10x7, 15,450, 8.35, 89, 1.60
APC 10x8, 13,000, 6.81, 87.6, 1.18
MAS 11x6, 13,700, 8.24, 67.6, 1.42

Tower Hobbies $15 tuned muffler (GMS):
Prop, RPM, Thrust (lbs), Speed (mph), HP
APC 10x8, 13,650, 7.17, 89.9, 1.27
MAS 11x5, 15,400, 9.32, 63.4, 1.71
MAS 11x6, 14,200, 8.85, 70.1, 1.58
MAS 11x7, 13,200, 8.41, 76, 1.47

For reference: My OS 55ax w/ 8 gallons through it turns APC 10x8 on the same muffler @ 13,950 on this setup/fuel. I confirmed its RPM at the same time of testing. This is with head shim removed on 5%.

Eganwp

My Feedback: (1)

My bench running tests for my new Viper 500 pylon plane. Other engines listed for reference.

+20*C, 3200ft ASL, 47% humidity, 0kph wind speed, 10% Homebrew @ 20% oil @ 80/20, all engines fully tuned and running on the $15 Tower Hobbies tuned pipe.

OS .55ax:
9x7APC = 16,440rpm = 175.4kph
9x8APC = 16,050rpm = 195.7kph

ASP .52:
9x7APC = 16,530rpm = 176.3kph
9x8APC = 15,990rpm = 195.0kph

GMS .47: (I've already done crank mods, sleeve mods and intake/exhaust ports durations modified)
9x7APC = 16,290rpm = 173.8kph
9x8APC = 15,720rpm = 191.7kph
Exhaust from 138* to 150*
Intake from 196* to 198*

Jett Tuned Pipe is in the mail!