They are making an engine they call Raptor for their planned giant rocket: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Raptor_%28rocket_engine%29" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Raptor_%28rocket_engine%29</a><p>It is not a swappable substitute for the Russian ones, because it uses a different kind of fuel and probably for lots of more complicated reasons.