Possible Clues:

• Prefix for 'charger' or 'jet'
• This charger improves a car's power
• Charger improves a car's power
• Knocks back old type of champagne with one of those efficient types in a car
• Fish minus tail in souped-up car
• Looking back, love type of champagne that has something similar to 21 across under the bonnet
• Dragster booster
• Sports car engine type
• Engine enhancer
• Prefix for jet or charger