You can buy this project and download/modify it how often you want.
Text on a path with spaces test Text on a path with adjusted spacing sample default spacing sample tspan x="10,30,50,75,95,110" y="110" sample tspan dx="0,10,10,10,10,10" sample textLength="140" sample textLength="70" sample kerning="10" sample textLength="140" lengthAdjust= "spacingAndGlyphs" sample textLength="50" lengthAdjust= "spacingAndGlyphs" sample textLength="140", kerning="10" lengthAdjust= "spacingAndGlyphs" sample letter-spacing="-3" sample sample textLength="140" word-spacing="2em" sample sample textLength="140" word-spacing="-5" lengthAdjust= "spacingAndGlyphs"