SpaceX engine production and rocket capacity

SpaceX is producing about 5 engines per week and has the factory capacity for 400 engines per year or about 8 engines per week. The Falcon 9 has 10 engines. One nine-engine first stage and a single engine second stage. The Falcon Heavy has 28 engines. Three nine-engine cores and a single engine second stage.
SpaceX should soon be pretty perfectly recovering the first stages and the fairing and other parts. Only the single-engine second stage will not be recovered.
If 2018 production was 400 engines, then ten Falcon 9 and ten Falcon Heavy could be produced along with extra single-engine second stages.
In 2018 and 2019, SpaceX could produce twenty reusable Falcon 9 and ten Falcon Heavy’s along with 220 expendable second stages.
There are currently only a handful of Falcon Heavy launches on the manifest. Although Elon Musk has mentioned they have a dozen commercial customers for the Falcon Heavy.
The Raptor engines are the same size as the Merlin engines.
The SpaceX BFR has 31 engines in the first stage and 6 engines in the second stage. SpaceX should be able to produce ten Big Falcon Rockets per year.