I would have to imagine that shock and tire technology has gone a lot farther towards making the overpowered sprintcars hook more of it up and go faster as compared to the midgets. Going fast in a midget with that tall a gear is about momentum and barely touching the steering wheel, not being locked down, and actually if a track is too sticky a midget can still bog the motor and scrub too much speed in a high speed corner... Sprintcars have always had way more motor than the rest of the car could handle effectively, but tires are so darn good these days and the shock companies are getting them so dialed in that we should be seeing sprinters (real sprinters, not the ones with umbrellas) gaining the most from all the advancements and dropping lap times easier than midgets.