It is unknown how much power this thing is making, but from the way it launches away from the camera, we're going to go with "a lot." The YouTube clip claims this is the Stage 10 tune, but who knows. Granted, the drivetrain probably can't take everything this Frankensteined engine could theoretically put down, so there's likely some kind of electro-wizardry at play limiting output until it at least hooks up. And if traction control still exists somewhere in there it might be helping keep the tires from melting. Chances are some part of the driveline will grenade itself if you try this too many times.
Even if it doesn't add any meaningful power output beyond the RS7 Performance's already plentiful 605 ponies, we can't bring ourselves to care. The high-pitched sound of the exhaust from those heat-wrapped pipes jutting out like the horns of a crazed antelope are simply priceless. Thank you, Russia.