Everything you want to know and more about the engine they used
http://en.wikipedia.org/wiki/NK-33
Amazing but not surprising:
The N-1 launcher originally used NK-15 engines for its first stage, and a high-altitude modification (NK-15V) in its second stage. After four consecutive launch failures and no successes, the project was cancelled. While other aspects of the vehicle were being modified or redesigned, Kuznetsov improved his contributions into the NK-33 and NK-43, respectively.
[5] The 2nd-generation vehicle was to be called the N-1F. By this point the Moon race was long lost, and the Soviet space program was looking to the
Energia as its heavy launcher. No N-1F ever reached the launch pad.
[6]
When the N-1 program was shut down, all work on the project was ordered destroyed. A bureaucrat instead took the engines, worth millions of dollars each, and stored them in a warehouse. Word of the engines eventually spread to America. Nearly thirty years after they were built, disbelieving rocket engineers were led to the warehouse. One of the engines was later taken to America, and the precise specification of the engine was demonstrated on a test stand.
[6]
About 150 engines survived, and in the mid-1990s, Russia sold 36 engines to
Aerojet General for $1.1 million each. This company also acquired a license for the production of new engines.
Aerojet has modified and renamed the updated NK-33 to AJ26-58 and AJ26-62, and NK-43 to AJ26-59.
[7][8] [9]