Anyone know the approximate time for getting from a standard charge of 240 mi, to a range charge of 260 miles using a 40 amp 14-50 and using a Supercharger?
14-50, just under an hour. Supercharger no idea, but my understanding is the it tapers off as the battery reaches full charge, so it may not be much faster.
If you simplify by assuming charging rate is linear, 37 minutes to go from 240mi to 260mi. Charging Model S | Tesla Motors
On the official Tesla forum a member posted various Supercharger charging times. It demonstrated that at high state of charge the Supercharger is no faster than a High Power Wall Connector (HPWC). For example, at a beginning state of charge of 74% it took 39 minutes to add 38 rated miles, or an average charging rate of 58 miles of range per hour to go from 74% to 88%. So assuming the average rate is no more than 58 miles of range per hour, a reasonable estimate would be around 25-30 minutes to go from 90% (240 miles) to 100% (265 miles) with a Supercharger. An HPWC would do about the same. A 14-50 would take about twice that time, as you stated, about an hour. Larry