The best car Consumer Reports has ever tested

Tesla (TSLA) just made Consumer Reports history.

The product testing agency on Thursday gave the new, high-performance P85D version of the automaker's Model S a rating of 100—a perfect score—calling it "the best-performing car that Consumer Reports has ever tested."

"It really blew up our system," said Jake Fisher, the head of automotive testing for Consumer Reports. "It actually scored above 100 in our system before we had to make some changes to account for this car."

Initially, the P85D Model S scored 103 points when Consumer Reports measured the car's acceleration, braking, handling and other key performance characteristics. Fisher and his team then modified their scoring model to make the P85D fit into a 100-point scale.

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When asked about the rating from Consumer Reports, Tesla spokeswoman Khobi Brooklyn said, "The Model S being the first car to receive 100 out of 100 points is truly a testament to our commitment to continually give our customers enhancements in range, performance and value, and ultimately a better driving and ownership experience."

The glowing review comes just two years after Consumer Reports gave the base model version of the Model S a near perfect score of 99 out of 100. At the time, that was the highest rating ever for a vehicle.

So what did Tesla improve with the high-performance Model S?

A big change is the addition of a second motor, giving the P85D dual motors and turning the single-motor, rear-wheel drive Model S into an all-wheel drive electric car that is more responsive and efficient.

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