In my experience the Jabiru will not last long if run at 2700 rpm as the
barrels will glaze and then oil consumption will go through the roof. I
have 2 Jabiru 2200 4 cylinder engines, one in my KR2 and one in a Jabiru
J160. The KR2 I have only ever flown hard, 2950 rpm plus, the CHT's are
around 310 Fahrenheit, and have had no problems with the engine. On the
other hand the J160 was flown more conservative, 2750 to 2800 rpm because it
constantly had CHT's around 360 Fahrenheit. The J160 has had the heads done
up 3 times, 2 new sets of barrels. I modified the cowling and the RAMAIR
ducts and bought the temperature down to 320 Fahrenheit and now run it at
2950 rpm and have no problems (and get there faster).
The same applies to the 3300 engine as I regularly fly with friends who have
the 6 cylinder engines have and also had problems. One of them would
throttle back for hours and fly at my cruise speed and that stuffed his
engine.
Jabiru specify:
Max. CHT (Climb) 200°C (392°F)
Max Continuous CHT (Cruise) 180°C (356°F)
In reality we have found max of 180°C (356°F) and cruise 160°C (320°F) gives
us best results.
I have my Grand Rapids EMS alarm come on at 175°C and rarely have that come
on. Another trick to play with is to try flying with the ball off centre and
see what that does to your temps. On climb in the J160 I fly with the ball
off centre to the left by about 1/16 inch and that drops the temp on the
hottest cylinder by 5°C........WOW.
Regards
Barry Kruyssen
k...@bigpond.com
http://athertonairport.com.au/kr2/
-----Original Message-----
In order to operate the Jabaru 3300 equipped Sonex as light sport, it
requires a placard on the panel stating that the engine RPM must be limited
to 2700 RPM after 5 minutes of flight.
Jeff Scott
Los Alamos, NM
----- Original Message -----
