The Low Fuel Alert is now in the Fuel Calculator PRO
Since version 6.07 the warning is no longer a separate overlay: it lives inside the Fuel Calculator PRO, with the same rule as always. A PRO plan feature of Raptor Racing Overlay.
The warning guards against the same thing as before: starting a race with a short tank after qualifying on low fuel. Before the start, if you're about to go out with less fuel than the series lets you load, a red ring pulses around the calculator and a strip says LOW FUEL · NEED and how much you're short. Once you load enough it goes away, and after the start it doesn't come back.
You don't have to do anything to get it: it's on by default in the calculator, and the margin you had picked in the Alert carries over to the calculator on its own. The standalone overlay is no longer in the menu. As always, it only reads iRacing data: you still set the fuel for your pit stop yourself.
The warning in the Fuel Calculator PRO: the red ring around it and, on top, the strip with how much fuel you still need.
Where it is now
In the Raptor Racing Overlay menu, open the Fuel Calculator PRO settings and go to the WHAT SHOWS tab: LOW FUEL WARNING is at the very top. There you turn it on or off with Show the warning, pick which side the strip goes on (Top, Bottom, On the left or On the right; the ring always goes all around) and the margin in Warn when short by: any amount, 5% less (the default), 10% less, 20% less or 40% less. When you change one of those options, the calculator shows the warning for a few seconds so you can see how it looks.
You can also turn it on or off and change its side by right-clicking the calculator, under Low fuel warning. Everything else is in the Fuel Calculator PRO manual.
