SpaceX changed the engines for the SpaceX BFS. They are all using non-vacuum engine nozzles.
This reduces the amount of payload that will be taken to space in the first version. It seems to reduce it from 150 tons to 100 tons.
In order to reduce the development risk and cost. They will only make a sea-level version of the Raptor engine.
There is an outer ring of cargo sections. Each one of the cargo sections can be replaced with a vacuum nozel of the Raptor. You would lose two cargo racks for each vacuum engined Raptor.
Replacing with cargo with vacuum engines will significantly boost the payload capability and power the SpaceX BFR and BFS.
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