Well how about this? If the Roadrunner was a zombie, then the Coyote could catch him right? No that wouldn't work either, cause then the bird would be the one trying to chase the Coyote. Even the words to the theme song would have to change...
"Coyote, zombie roadrunner's after you
Coyote, your brain he wants to chew"
So the entire concept is unworkable and I regret having mentioned it.
Central gag of that cartoon was never speed differential anyway; it was that Coyote is really really stupid. Wile's poor understanding of conversion ratio demonstrates that. See, a conversion ratio really has nothing to do with a Missionary's annual performance review. (yeah, I was surprised too!)
Conversion ratio is about how much energy it takes to convert an energy source to a useable form. Coyote was trying to convert Roadrunner into calories, and he was just wasting way more calories than he could ever hope to replace.
We know about conversion ratio due to the fine work of Sir Isaac, a man so smart they named a cookie after him. The amount of energy in our universe is constant; all that happens is modification in energy's mode of expression.
It takes a certain amount of energy to convert an energy source, and on that end the math is fairly non-controversial.
A solar energy panel for instance? Its service life can be estimated, and can be expected to deliver X number of watts during that time. Well it takes watts to mine and refine the component materials, then construct the solar panel. And at end of its service life, takes watts to responsibly recycle the components.
Divide construction/deconstruction watts by estimated service life watts and that's conversion ratio. A really good one would be .001 which solar panels ain't got. A dumb useless project not worth doing ratio would be 1.0 and Mr. Coyote running around the desert in a fur coat, well that looks like about 167.5 to me.
You'd think energy policy would be a snap, simply assign conversion ratios to all proposed projects, and the best ratio is what you want more of. By that thinking, the cheapest US energy sources are:
Hydro-electric, nuclear, coal, wind power, and petroleum.
All the controversy comes into it post-use. Lots of nice folks want to weight the ratio with intangibles. Like coal for instance? Really great conversion ratio there, but in this country are some few sissies who don't like breathing sulfur dioxide for some reason. They insist the inconvenience of adding noxious gas to the atmosphere get added to a perfectly nice conversion ratio that was minding its own business..
So the debate rages on about which form of energy is really most efficient, and people on all sides have their agendas. That's why these groups have conspired to remove the good old, intensely violent cartoons from television.
They don't want we, the American people, to be reminded of nature's miracle, a substance with a conversion ratio of .0000001 or something. Yep, I'm talking about spinach. Just think of it? Skinny little Popeye eats one can and all of a sudden he's lifted that grand piano off himself and he's wailing the tar out of that big bully, who is either named Brutus or Blutto. (I find that quite confusing, and Congress should hold hearings about it)
Spinach could probably fuel not only our cars, but the Space Shuttle too, and a group of shadowy figures are suppressing that info by keeping Popeye off the air. Back in the 1960's when cartoons were non-stop carnage, we weren't importing so much oil. Coincidence you say? Ha! Go ahead and live in your little fantasy world if you wish.