Ephraim was on target as Rangers eventually found their feet to hit five past Exeter after a goalless first half in their Carling Cup first-round clash.
Jim Magilton's side now head back to the south-west to take on Plymouth looking for their first Championship win and Ephraim expects another tough test.
"We'll need to start well. Plymouth is never an easy place to go and we'll need to be much better than we were in the first half at Exeter," he said.
"The gaffer really got stuck into us at the break on Tuesday. We knew we weren't playing to our usual high tempo and he reiterated that in no uncertain terms. But to be fair to the lads, we responded with a display full of quality and class in the second half.
"We'll need to show that again at Plymouth for the whole 90 minutes on Saturday."