The two quickest Corvettes to lap our figure-eight course ( Grand Sport and Z06 / Z07 ) tied at 22.3 seconds . Our editors often say the 2017 Grand Sport was the best-balanced Corvette ever , with the grip of the Z06 / Z07 but an ability to put its power to use that the Z06 / Z07 lacks . Its impressive lap proves this . We expected a similar lap time from the ZR1 duo . However , in a case of bringing a pair of howitzers to a knife fight , they only managed to circle our racetrack in a bottle in 22.7 and 22.9 seconds . Why ? It ’ s simply too difficult to use all of the power in a parking lot , and there ’ s twitchiness to it that previous Corvettes didn ’ t suffer . A mere week after the infamous and unfortunate Detroit Grand Prix pace car wreck , test driver Kim Reynolds said : “ Brakes are killer — you can drop the hammer at virtually the last second . Turn-in feels like lateral suction , but after that there ’ s a bit more understeer than I ’ d like . Midcorner grip is great , then exiting , the tail walks ( using third gear ). It steps out in a digital way — just pops out a notch very quickly , and you have to respond very modestly to it to avoid a “ tank slapper .” Tremendous power — wow wow wow .” So besides this tendency to “ walk the tail ,” there wasn ’ t as much lateral grip on the skidpad portion , either . Where the Z06 / Z07 sustained 1.17 g and the Grand Sport 1.18 g , the ZR1 pair managed 1.07 g and 1.11 g . It ’ s not much difference , but it all adds up .
Like a Pro a car parked on the side of a road © Motor Trend Staff What the ZR1 was built to do was set records at real racetracks . Luckily , we ’ ve got “ the fastest track in the West ” at our disposal , and a tame race car driver , too . Randy Pobst has set and reset the lap record for production cars at Willow Springs , so he knows his way around . Having recently set a production car lap record in a 2019 Corvette ZR1 at Road Atlanta , he knows his Corvettes , too . Did the ZR1 set another record at the “ Big ” track ? Sadly no , but it did outpace the last Z06 he drove there by a significant 1.3 seconds . In order , the top five spots currently belong to a 2018 Porsche 911 GT2 RS ( 1:21.08 ), 2018 McLaren 720S ( 1:21.75 ), 2018 Lamborghini Hurac n Performante ( 1:22.53 ), 2015 Porsche 918 Spyder ( 1:23.54 ), and 2017 Ford GT ( 1:23.69 ). In sixth place by a mere 0.01 second , the 2019 Chevrolet Corvette ZR1 with the ZTK package made a 1:23.70 lap . With Chevrolet on hand to support the effort and three sets of tires sacrificed in the process , it was the best that car could do that day . The “ low-wing ” car was just 1.15 seconds behind , its 1:24.85 earning 11th place overall .
When asked to compare the ZR1 to the Z06 , Pobst said , “ The ride is more compliant , especially in the most aggressive mode . Brakes are still strong — as always , world class . The [ ZTK ] wing does add high-speed stability . Even the ZR1 without the aero package is better-balanced [ than the Z06 / Z07 ] in high-speed corners .” However , he followed up with , “ While the car has a big bump in power [ over the Z06 ], it ’ s still twitchy trying to accelerate in the lower gears . And that ’ s the ‘ Vette ’ s great downfall .”
When asked about how the ZR1 handled the duress of making three or four hot laps in succession , Pobst said , “ Happily , greatly improved cooling keeps both intake temps — as a result of the larger supercharger and intercoolers — and engine coolant and oil temps to more survivable numbers . I saw stable readings under 220 for water and under 275 for oil . Still rather high , but much better than the pegged readings of the poor Z06 .”
32