Fun fact! It's still racist.

Uhmmmm, pretty sure it's worse than that. My understanding of the term is that it comes from cars, where cheaper Asian cars were entering the American market and were called "rice burners" (racistly), and I'm pretty sure from there the concept of decking out a cheap car with spoilers and ground kits and a wild paint job and stuff was called "ricing" because it was a thing in the Asian communities. As in "ricing a car" is "doing what an Asian would do to that car, and you know how they're all about rice"

I'd be happy to be wrong here... but I think that's the history on that word.

I believe ricing roots from the derogatory word for Asian mod cars, known as ricers. Customizing or modding them was the deal.

It is an extension/evolution of the idea of ricing cars. Originally it was something like Race Inspired Cosmetic Enhancements. Basically stuff that makes your car look "racier"/faster, but does nothing for performance.

Edit to add - That is probably backronym to cover up for the mostly racist origination of that term. I can't be sure.

I believe it refers to a similar concept in the car modding scene.