In 1951 he travelled abroad, with Peter Bell's 2-litre E.R.A., to finish 3rd overall in the Susa/Mont Cenis hill-climb and 4th overall in the Aosta/Grand Saint Bernard hill-climb. With a Cooper 500 he also competed in the German Freiburg hill-climb where he was runner-up in the 500 cc class to Stirling Moss. Wharton won the Freiburg event outright in the E.R.A. on 5 August, climbing the 7.4 miles of the Schauinsland Pass, in 8 minutes 5.33 seconds. On 19 August he was fastest at the Vue des Alpes hill-climb, with a time of 3 minutes 57.8 seconds. He won the British Hill Climb Championship every year from 1951 to 1954, and remains the only driver to have won four successive BHCC titles. Other successes with ERA R4D included winning the Brighton Speed Trials in 1954, 1955 and 1956.