Until the engine melts. If the same air is recirculated over and over,
with no exit, but more gasses are introduced in the form of the oxygen
being injected, you have a constantly increasing volume of gasses that
are getting hotter and hotter. I wonder if it could melt even a
ceramic engine?

I could almost see this working if he were to limit the amount of
exhaust gas that was recirculating into the engine... Oh wait a
minute... That sounds familiar. EGR. hmm... In all fairness I realize
that this is totally different from EGR, but I still make the
assertion that plumbing all of your exhaust back into an engine will
never work. Even if you want to cram a little oxygen in there to
sustain ignition.

A new take on the old EGR valve!

I'd love to see it idle for a half hour, if it lives that long.

LOL

RK