I've been slowly building my
RV-8 with 13BT engine for about 14 years...!
On June 13th 2013 it received the coveted Airworthiness Certificate. That
same day I detonated my engine due to the trailing spark plug holes being
machined oversize in an attempt to improve the single spark plug power, should
the leading plug ignition fail. This, and possibly advanced ignition, and
possibly over-boost detonated my engine on it's first high power taxi test.
That took about 2.5 seconds.
Now I've rebuilt the engine with new unmodified rotor housings, and it
runs better than ever. I've re-marked the timing marks on the pulley, and
reset the timing, though not to 4000 RPM yet. today I checked it. At 3000 RPM
my hat and hearing protection blew off. 11 degrees BTDC, and 16" manifold
pressure.
I've been taxiing around at modest RPM, it's great. I've consistently
been idling at about 1600 RPM, (730 prop RPM) and sometimes as low as 1490,
(680 Prop RPM) smoothly. That is slow enough to keep the brakes from getting
too hot.
I've done run ups and brief bursts of power to 4200 Engine RPM, (1917
Prop RPM) which is about 32" manifold pressure, and seen 37" manifold pressure
briefly. I know this is not enough power to take off, although I have done a
Pre-take off to 50 MPH with this power before powering down with roll out to
the end of the runway. I suppose it would fly off and maybe clear the
trees at this power. I've lifted the tail, and rocked the wings with the
ailerons. It steers well and the brakes work.
The water level in the engine stays up between flights as does the oil,
and the water temp today was consistent 163 F oil about 173 with the
highest observed 183F. I did about 4 pre-take off passes with taxi back, with
excellent temperature control and throttle response.
A couple of oil fitting were tightened looking for an oil seep.
7.3 hours engine running time on the EM2, about 2 hours since the engine
overhaul.
I don't think I'm at all ready to fly this thing. I'm missing something,
so offer up some advice, I'm all ears!