\header
{
  texidoc = "Grace note runs have their own spacing variables in
  @code{Score.GraceSpacing}. So differing grace note lengths inside a
  run are spaced accordingly. "
}

\version "2.10.0"

\paper {  ragged-right = ##t }

\relative c''
{
  c4
  \grace { c16  }
  c
  \grace { c16  }
  d
  \grace { c16[ d e f] }
  c
  \grace { c8[ c16 d c8]  }
  c
  \override Score.GraceSpacing #'spacing-increment = #2.0

  \grace { c4 c16 d16  }
  c
} 
