Check out this video of the C8 Corvette breaking the 700 Horsepower mark thanks to Extreme Turbo Systems.
Per Extreme Turbo Systems video on YouTube:
Extreme Turbo Systems is continuing to push the boundaries of the C8 Corvette with our proprietary tuning solution and methanol kit. We put down 736 horsepower to the wheels @ 7.5 psi. To our knowledge, this is the first C8 Corvette ever to be tuned and break the 700whp barrier. We have a lot more in store for this platform, so make sure to follow us for more updates!
Here is more information about this C8 Corvette Twin Turbo set up and how they are making 736 horsepower with this prototype system they are still building and not currently for sale.