\relative c'' <<
\override Score.SpacingSpanner.strict-note-spacing = ##t
\set Score.proportionalNotationDuration = #(ly:make-moment 1/16)
\new Staff {
c8[ c \clef alto c c \grace { d16 } c8 c] c4
\relative c'' <<
\override Score.SpacingSpanner.strict-note-spacing = ##t
\set Score.proportionalNotationDuration = #(ly:make-moment 1/16)
\new Staff {
c8[ c \clef alto c c \grace { d16 } c8 c] c4