Hi Kelly and Kraivuth,
I emailed this to Kelly as well but not sure if it went through so I'll ask here as well.
Went out again tonight to fly the reaction, still having some issues with the 600.
The EGT probe was the cause of my starting problem, thank you Kelly for getting
me a new one.

Tonight I started up the engine, temps were a little on the low side, checked the
probe and it was not in the tail cone far enough, no big deal, probably got bumped
during loading, as you know the reaction offers no protection to the engine.
Started it again and all was good, 55,000 idle, about 425 degrees, 160,000 top at
about 575 degrees. Taxi'd the plane out (grass runway and fairly rough) and went to
throttle up to take off, engine quit and flame shot out the back. Shut everything
down, no big deal, I figured with the bouncing on the ground it probably got a
bubble in the fuel line. Took it back to the pits, refueled just to be sure,
started it up, waited for idle set, then throttled up slowly as I always do after
start, everything was fine, go to taxi out, advance the throttle, same thing, quits
and shoots flame out the back. So, this time I start it up again, everything is
fine, throttle up slowly, no problems. Go back to idle, then throttle up again, I
didn't slam the stick forward, but I pushed it forward as I would on takeoff or
during flight, the engine got to about 88,000rpm and quit the same way. So I
started it again, and have been able to replicate the problem everytime. If I
advance the throttle slowly it's no problem, if I push it up more aggressively it
quits and shoots flame out. I figured it must be an air leak so I checked all of my
connections and there's no leaks anywhere, but since I had unhooked most stuff and
put it all back together I tried one more time, same problem.

I'm at a loss here, any wisdom, words of advice? I probably won't have a chance to
run it again before princeton, (september 13 - 16) but if there's something I should check that will be
easier to check at the shop I'd rather do it here than there.
Thanks
Jeremy