fine-tune

Verb

• make fine adjustments or divide into marked intervals for optimal measuring
  • calibrate an instrument
    
  • graduate a cylinder
    

• adjust finely
  • fine-tune the engine
    

• improve or perfect by pruning or polishing
  • refine one's style of writing
    

Related words

• Synonyms: 
  calibrate , graduate , tweak , polish , refine , down