Something’s off with the Corvette C8 power numbers
Known Corvette C8 facts and rumors
The Corvette C8 has some crazy specs and horsepower coming with it if it ever hits the streets. A few expert drivers have had the pleasure of testing the C8 and some weird findings have been made.
So what do we know about the Corvette C8? Officially the C8 is supposed to put out 495hp and 470lb-ft of torque. How is this determined? Using the highest of safety specs and verifications. Specifically, the Society of Automotive Engineers certifies the figures. These figures are obtained using the strictest of protocols. So what are the rumors?
Well, Motor Trend was able to test a pre-production Corvette C8. They were able to keep it for a couple of weeks to really get a feel for the ‘vette. Motor Trend decided to run their own tests on the Dyno to see what the unofficial readings were. Conclusion: GM has REALLY undersold the output on the Corvette C8.
So what IS the real story?
Motor Trends ran the Corvette C8 six times on the dyno. The initial test was run in the fifth of six gears, The ‘vette put out 558hp and 515lb-ft of torque. That’s a lot higher than those touted by GM. Obviously, with that great a difference the guys at Motor Trend decided to make a second run on the Dyno.
The second round, done in sixth gear, produced 558hp and 512lb-ft of torque. Based on their calculations for parasitic loss, the figures would be about 656hp and 602lb-ft of torque. Crazy. That’s a lot higher than the official figures put out by GM.
Officially the C8 is supposed to put out 495hp and 470lb-ft of torque.
The guys decided to do a few more tests to see how the figures would add up. The third and fourth tests were both done in fifth gear. The third comes in at 561hp and 515lb—ft of torque. Taking into account parasitic drain, that means 660hp and 606lb-ft. The fourth test results were 561hp and 523lb-ft of torque, 654hp and 615lb-torque with parasitic drain taken into consideration. Now everyone is wondering exactly how stringent those Society of Automotive Engineers’ tests are. Stricter than a grandmother with chancletas.
These figures are obtained using the strictest of protocols.
Naturally, curiosity peaked, the guys decide to run a few more tests in sixth gear. Those tests result in figures of 478hp and 544lb-ft of torque for the fifth run. Assuming the same parasitic loss as prior tests, these figures would be 562hp and 630lb-ft of torque. The sixth run resulted in 495hp and 470lb-ft of torque, non-parasitic assumptions being 562hp and 640lb-ft torque.
GM was contacted for a response as to why the reported figures were so different from the actual experience of Motor Trends experts. They provided two inter-related reasons as to why that may be. The first is that the Corvette produces more horsepower when it is cold. This didn’t fully explain the higher figures still produced when Motor Trends experts had the Corvette C8 on the dyno.
The second reason is that strict protocols required by the Society of Automotive Engineers causes the car to get hotter than the tests run on the Dyno. This would account for the lower figures put out. As the outputs are certified by the Society of Automotive Engineers it would stand to reason that they operate by the strictest protocols and use the most conservative figures in order to avoid any liability or other issues.
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