RCMF Donations

Enjoy using RCMF? How about a wee donation to help us keep you in the style to which you've become accustomed?

Welcome to RCMF. Please login or sign up.

August 24, 2019, 06:34:53 am

Login with username, password and session length

Summary Performance for Various Engines

Started by ogg2000, September 27, 2016, 17:11:48 pm

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

ogg2000

September 27, 2016, 17:11:48 pm Last Edit: October 02, 2016, 18:35:56 pm by ogg2000
Greetings all,

This looks like a useful thread, so I thought I would add some summary performance figures for some of my engines. 

YS DZ160, 20% heli fuel, 18x8 wooden prop -  8800 rpm running fairly rich. (staggeringly powerful and responsive engine, and very noisy on this prop).

YS110, 20%  heli fuel, 16x6 APC - peak at 9500 rpm but a safer setting of 9300 rpm (to avoid going lean in the air)

YS 91AC,  20%  heli fuel, 16x6 APC - peak at 8700 rpm  - found this a bit difficult to tune, I'm not sure why

Saito 182TD 16% fuel. Menz 16x8 - peak at 9200 rpm.  This is a hard engine to tune, especially for a reliable idle - sometimes it will idle as low as 1900, but much of the time loses one cylinder even above this.  It's always the same cylinder too - I've adjusted the air bleed screw with little effect, so I'll have to work the main needle next. This engine has little vibration, a rather unusual exhaust note but loud also on standard stub pipes, and has great throttle response. This is a light engine for the power, considering it has a radial mount, and it's short too, so can fit many airframes that a 150 or 180 would be too large to fit.

Saito 125 16% fuel APC 16x6 peak at 8700 rpm, changing to 20% gives barely 100 rpm more. Interesting comparison to YS110, trading 100g extra weight for 600 rpm more with increased fuel costs. This engine runs fine on 10% too. Engine fitted with Turboheader exhaust - which is the only type I've tried that doesn't come loose after two or three flights (even with PTFE tape or high temperature thread lock).

Just acquired  a used OS 120 Surpass III pumped - 16% heli fuel, APC 16x6, 8700-8800 rpm.  This was fitted with a Turboheader exhaust  - only fitted because its much smaller that the OS exhaust.  This was tested mounted inverted in the model.  I found it impossible to get a reliable idle without the battery connected. I could get a solid idle around 2400-2500 but it would eventually cough and die.

Regards
Dave