Firepower rhymes with:
airpower, airpower, brainpower, horsepower, manpower, seapower, willpower, airpower, belflower, bellflower, brainpower, cauliflower, coneflower, cornflower, eisenhower, fillauer, hightower, horsepower, hufbauer, icenhower, landauer, manpower, mayflower, safflower, seapower, sunflower, wallflower, wildflower, willpower, zembower
Firepower sounds like:
faerber, farber, farberware, farver, ferber, fervor, firfer, forebear, forever, frappier, furber, furfaro