----- Original Message -----
Sent: Monday, November 17, 2008 9:38
AM
Subject: [FlyRotary] high EGT temps Rotor
#1
Rotorians,
Now that the airplane is painted, weighed, prop
ballenced and etc. I'm into tuning and getting comfortable with the
engine. Yesterday I noticed that as I ran the engine up, #1 rotor EGT
trailed #2 by 20 to 30 degrees and then at about 20 inches of manifold, #1
started climbing rapidly! At max static throttle 5828 rpm (prop
speed of 2045) or so, #1 runs to 1640 degrees while #2 maxes at 1480
degrees. I played with the mixture etc. No difference. I
have checked the plugs and swaped them. No difference. Stock RX-7
plugs. Pulled one and then the other secondary inj.
connector. It starts and runs and then drops off as RPM gets high.
Same on both #1 and 2. Swapped injectors. No difference.
Tryed using Mode 4, both to increase mixture and then to decrease. No
difference. Reset Mode 4 back to default. Swapped EGT
probes. High temps showed up on #2 on EM-2. Swapped back.
Checked the archives. Nothing. The EGT probes are installed
through holes in the exhaust 5 inches from the engine outlet. So I
am at a loss. Any thoughts on what might be causing this? Engine
basically running smooth and strong. Months ago, I remember getting 6150
RPM, but couldn't get it to run long enough to check out EGTs. Cooling
problems. A couple of other things that may or may not have anything to
do with this. Manifold display on EM-2 sometimes jumps around some.
I have tried porting to the front of the intake and to the rear.
Now I have it teed to both. Auto tune tries to work, but does not.
(O2 sensor installed at end of tangenial) I ran it almost 2.5 hours
total yesterday. 11.7 hours total. since last December. Quietest
airplane on the field. Lots of attention from other pilots.
Don Walker
RV-8 N113BR
Renesis 4 port. RD-1c
EC-2 EM-2
Tuned 17.5 inch intake.
Tuned 24 inch exhaust into tangetial
premuffler
catto 76/88. Field elevation 5000 ft.
density 6200