Id turn the car off instead of putting itinto neutral, and revving the hell out of the motor. I'd just turn the key off one click. Yeah you loose power steering & power brakes, but the car will still be controllable.

Bottom line, the Bypass valve is faily useless unless you like driving through lakes; it even sucks in some hot, less filtered air from the engine bay. For all the trouble & risks, its really only a "feel-good" mod.