ΔE 14.5, fair: the same colour family, but not a straight swap. Engine Gray is a little lighter, more saturated than Purple Black.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 15). Engine Gray is a little lighter, more saturated than Purple Black.
The same difference applies the other way round: Purple Black is a little darker, more muted.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Purple Black on the colour wheel See Engine Gray on the colour wheel
All matches: Purple Black equivalents · Engine Gray equivalents