Hi everyone, I have a graph here but it's in increments of X=0.25 and Y=25 I'd like to change mimic this graph and change the increments to X=0.5 and Y=25 but I'm not sure what the equation is...

For all the math experts here, does anyone know how to find the equation just by looking at the graph? It's a "dyno sheet" of a car.

Thanks in advance!