Complex sentence: The team selected gas turbine power as the solution, and after initially considering the Rolls-Royce Dart, but during the time Jones was arranging funding, an experimental engine built by Leyland for truck use became available, which was designed to be much less expensive.
Split into simpler sentences: The team selected gas turbine power as the solution, initially considering the Rolls-Royce Dart. During the time Jones was arranging funding, an experimental engine built by Leyland for trucks became available, which was designed to be much less expensive.