ΔE 96.9, loose: different enough that you should pick on purpose. Fluorescent Orange is noticeably darker, warmer than Speed Yellow.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 97). Fluorescent Orange is noticeably darker, warmer than Speed Yellow.
The same difference applies the other way round: Speed Yellow is noticeably lighter, cooler.
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 Speed Yellow on the colour wheel See Fluorescent Orange on the colour wheel
All matches: Speed Yellow equivalents · Fluorescent Orange equivalents