[Grovlet]

I would think if he stays off the go-go pedal, and fills it up with Premium he'll be fine.

Octane Booster probably won't help, as most of them only raise the octane 1/10th of a point, so you'll need to add way to much to make it matter.....

It's really not worth the effort to drain the tank, just need to keep it from detonating by driving it easy until you can run through the 'Regular' gas.