The only thing I could find in any of the PDX literature was "Any video equipment must be rigidly and securely mounted, metal-to-metal. The stewards and instructors have the discretion to request that cameras and other equipment be removed if they feel it is blocking the driver’s vision or encouraging inappropriate or unsafe driving." So, it will ultimately be the tech inspector's call. I would definitely bring it - the worst that could happen is you would have to run without it.