When a Ferrari goes up in smoke, you might get a lick of flame, a bad smell, and that's about it for the first twenty minutes. When a fully-fueled race car goes up in flames, it's like Satan himself is fighting his way out from under the hood. And a Viper at Sebring just went up like that.
This is what we experts in the business call a "holy crap raging inferno." The car goes from a few wisps of smoke to all-out hellfire in less than a minute, and that's partially because of how much fuel was still in the car since it was near the start of the endurance race.
Protip: if you ever see smoke anywhere near your car, pull over safely, and then get the hell away from there as fast as you can.Just like Ben Keating, the driver, nicely did. Your car could do its best impression of a fire tornado. You're welcome for that helpful hint.
UPDATE: And this is what the remnants look like afterwards: