(Idiomatic) to make something, especially a machine, better (faster, bigger etc.)
To screw up is to make a mistake or error.
(Physics) To increase the heat energy of an object.
Find another word for hot-up. In this page you can discover 5 synonyms, antonyms, idiomatic expressions, and related words for hot-up, like: soup-up, hop-up, heat-up, screw up and heat.