Dread overtaking Rolls-Royce with current car (7)
I believe the answer is:
ferrari
'car' is the definition.
'dread overtaking rolls-royce with current' is the wordplay.
'dread' becomes 'fear' (synonyms).
'overtaking' means one lot of letters goes inside another (a word 'takes over' another set of letters).
'rolls royce' becomes 'rr' (short for Rolls Royce).
'with' says to put letters next to each other.
'current' becomes 'I' (physics symbol).
'fear' placed around 'rr' is 'ferrar'.
'ferrar'+'i'='FERRARI'
(Other definitions for ferrari that I've seen before include "Italian racing car company" , "Italian sports car" , "Type of racing car" , "Sports car brand" .)