***EDIT*** Updated with SNES vis OSSC Line double and quintuple modes.***EDIT*** I don't have an OSSC yet, so I can't compare the original SNES on my modern TV. Unfortunately the component/composite port on my VIZIO 55P-F1 does not support 240p.
Each frame is 1/240th of a second, or 4.166ms. I averaged the number of frames from ten jumps to obtain the results.
Times in milliseconds represent the amount of time it took for Mario to jump after my finger hit the bottom of the button. I got some input lag numbers from my TV using a GoPro shooting 240 FPS.