You don't need to be speeding to be busted for street racing so a cop doesn't need to use a radar or laser to write the ticket. In fact, when you start to rely on them too much you become even more inattentive and more likely to get a ticket. If you actually get pulled over and the cop sees your radar detector, you can kiss any chance of getting off with a warning goodbye.
While you're humming along at above the speed limit with your radar detector issuing no warnings, you can be paced by a trooper on the ground or timed by an airplane.
There's no replacement for good old fashioned common sense and keeping your wits about you. Spend the dough on go fast goodies.
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351W 89 Mustang GT Convertible