How Much Power Does the 2020 Chevrolet Corvette Really Make

[Richard G.]

Lots of speculation on the HP numbers after this Motortrend article. Just interesting enough to pass on.
I believe something was amiss but still entertaining. The additional acceleration (to 60 in under 3 sec) is explained by the wider tires, more traction and better gearing.

How Much Power Does the 2020 Chevrolet Corvette Really Make? We Take it to the Dyno and Find Out

And here is the rebuttal.

https://www.motor1.com/news/378121/2020-chevrolet-corvette-dyno-test-exclusive/

I for one thought HP was dead in the 80's and would never come back. Certainly not to the level we see today. Even at 495 hp and 470 lb-ft the new Corvette promises to be a great car. I did drive 2019 Grand Sport that a friend just purchased. What a wonderful car and a thrill to drive. Best thing, the sound (optional exhaust) and the way the automatic shifts.


Rick

[Duke W.]

Re: How Much Power Does the 2020 Chevrolet Corvette Really Make

The second article draws a good case of why the test numbers couldn't be true. On a naturally aspirated engine peak torque is basically a function of displacement and compression ratio, and max BMEP can be easily calculated from peak torque.

As to why, the full context of the test data was NOT provided, which happens all the time on the Web when guys report dyno test results. For example, what kind of dyno was used and what, if any correction factor was applied to the observed data.

In my experience Dynojet inertia type chassis dynos give fairly accurate and consistent results (Mustang dynos typically read lower), and test data from different times and places can usually be correlated by applying a consistent correction factor and the default is "SAE net", which is what manufacturers use to quote advertised horsepower at the flywheel. However, sometimes the old "SAE gross" is applied, and for an engine with an efficient exhaust system the difference is about 10-12 percent, and this would account for the higher than expected numbers. SAE gross is still used today by dyno shops that test engines on lab dynos. The output data whether tabular or graphical should always state the type of correction factor used, if any, to "correct" observed results to a common datum.

Like I said I run into this on the Web all the time. Guys don't provide full context and end up comparing apples and oranges.

MT Editor-in-Chief Ed Loh lives half a block away from me, so I will question him on the test procedure.

Duke

[Michael J.]

Re: How Much Power Does the 2020 Chevrolet Corvette Really Make

Well, the bottom line for me is, until I see a verified dyno test that shows it north of the 755 HP my '19 ZR1 has, I have no interest.