I'd bet he wasn't going any faster than 135 mph, and those cameras aren't designed to measure speeds that high. Hence the false measurement of 147 mph. I don't think that car can go that fast, although we do get some strong winds in Phoenix occasionally and he might have caught a helping wind.
Since C&D lists the stock at 137, perhaps so.
But 135 would still enough to get the lad a ticket or two.