Well, Nextel switched to Sprint, so this changeover to
ethanol, from unleaded gasoline, shouldn't be difficult.
Now, if we could get them to switch to Li-ion batteries,
I would become a fan of NASCAR. I suspect we are a few
decades away from this being even a remote possibility.
I hope GM starts spending more time on transforming vehicles they actually manufacture, than the ones they sponsor.

This would bring NASCAR back to it's origins as bunch of Hillbilly revenue runners.

I think they should let the teams do whatever they want with Hybrid and/or EV power - keep it unregulated, but they should keep all the HP and thottle plate restrictions in place for the gas engines. That way we might see some very interesting technologies being developed to get a few extra HP or laps without going into the pits. Racing is boring now because the cars are too balanced - lets mix it up a bit.

do all nascar motors make about the same Horse power or are they trade secrets........

It would be interesting to limit the amount of fuel they are allowed use / carry - and reduce it year by year, say 4% / year for 10 years.

Using ethanol instead of gasoline is just greenwashing.

While I agree they should reduce the amount of fuel each year, this reduction should apply to the whole country. There is nothing like a budget to focus the mind and encourage innovation.

How about NASCAR Nextel Cup on Ethanol, and Truck Series on Biodiesel?

There isn't a large disparity between horsepower and torque figures for NASCAR cars, they usually hover around the 850hp range and if I'm not mistaken, a 750cfm carburetor is still mandated. The only real technological progress made in NASCAR in the last twenty years has been in the driver safety arena, it's like they're engineered to be giant bumper cars.