I got an unofficial-official confirmation over the phone that they are allowed to run 125% overdrive which is a significant advantage over their US counterparts. Like I said, 10 pounds of boost and about 400 HP just in the pulley change. Still a great run, because to do it you have to be able to get the car hooked up.
In 2001 NHRA reduced the overdrive due to bad advice from misguided individuals who thought it was going to save the racers some money by lowering boost levels. Instead, the racers were forced to buy 8-10 superchargers to find the best one, spend thousands on coatings, rev the crap out of the engines to replace the lost boost resulting in destroyed engines due to valvetrain failure, etc. And 12 years later it still stinks.