On one hand, Buran creators explicitly looked into American design while working. On another, important parts in design are completely different. Saving expens

On one hand, Buran creators explicitly looked into American design while working. On another, important parts in design are completely different. Saving expensive main engines? Not on the orbiter, but on separate rocket, in subsequent plans. Solid fuel boosters? Too risky, better use the world's most powerful liquid fuel engines. Carcinogenic onboard propellants for RCS? Use cryogenics instead, and make sure they're preserved well for a month of flight. A few improvements here and there, and while externally Buran is quite similar to Shuttle, the whole launching stack is already less so, and the list of different details is not that short.