Different (disasterous!) Particle Physics Render with Evee and Cycles?

Can someone help me figure out why my Evee render looks fine, but my Cycles render (first 120 frames shown) looks like a major disaster?  Using 2.80 rc2.

Evee:  https://www.jimby.name/vids/R102_EVEE0001-0300.mp4

Cycles: https://www.jimby.name/vids/R102_CYCLES0014-0120.mp4

Blend File: https://www.jimby.name/vids/lowpolyrocket_102.blend

My only significant change is that I flipped the normal on the Smoke Emitter so it points downward.  I also set the Velocity and Object Velocity to 0.1m/s.

I'm really perplexed here as to why one looks fine and the other looks like, well, disaster.

Jim B.