Engines in Vacuum

I Like KSP Ro Mod where Engines Thrust are Focused In one Direction or In one of the Four Expansion Regimes of a de Laval nozzle,Over-Expanded while in the Earths Atmosphere.While 55000km from Droo Ground,The Engines are now Ambient Nozzle or the Engines are now Distributing a Straight Thrust.When In the Vacuum of space,The Engines go Under-Expanded Nozzle or the Thrust is Distributed Around the Engines.

Heres What I'M Talking for

The Top is the under expanded nozzles in vacuum
below it was ambient nozzle or thrust is straigth.under is Over Expanded Thrust or has an aerospike thrust.

heres what get about Four Expansion Regimes of a de Laval nozzle in Wikipedia:

The most commonly used nozzle is the de Laval nozzle, a fixed geometry nozzle with a high expansion-ratio. The large bell- or cone-shaped nozzle extension beyond the throat gives the rocket engine its characteristic shape.

The exit static pressure of the exhaust jet depends on the chamber pressure and the ratio of exit to throat area of the nozzle. As exit pressure varies from the ambient (atmospheric) pressure, a choked nozzle is said to be

under-expanded (exit pressure greater than ambient),
perfectly expanded (exit pressure equals ambient),
over-expanded (exit pressure less than ambient; shock diamonds form outside the nozzle), or
grossly over-expanded (a shock wave forms inside the nozzle extension).
In practice, perfect expansion is only achievable with a variable-exit area nozzle (since ambient pressure decreases as altitude increases), and is not possible above a certain altitude as ambient pressure approaches zero. If the nozzle is not perfectly expanded, then loss of efficiency occurs. Grossly over-expanded nozzles lose less efficiency, but can cause mechanical problems with the nozzle. Fixed-area nozzles become progressively more under-expanded as they gain altitude. Almost all de Laval nozzles will be momentarily grossly over-expanded during startup in an atmosphere.[4]

Nozzle efficiency is affected by operation in the atmosphere because atmospheric pressure changes with altitude; but due to the supersonic speeds of the gas exiting from a rocket engine, the pressure of the jet may be either below or above ambient, and equilibrium between the two is not reached at all altitudes (see diagram).

thats it wish this comes and upvote if u agree.