Matt McKeown, 52, from Plymouth, reached 44mph (70km/h) two weeks ago - but the record was not official.
"I have to submit all the evidence for Guinness to ratify, but it should be official in a few days," he said.
"It should have been faster, so I'll definitely be coming back for another attempt."
Mr McKeown used a modified second-hand Chinook helicopter starter engine to power the shopping trolley, which has been stabilised with go-kart wheels.
"We've also put an after-burner on, which in theory could have taken the speed up to about 80mph (129km/h), but it didn't work, so I'm disappointed."
The record attempt had to be carried out twice in opposite directions and Guinness World Records will accept the average speed.
"Our top speed was 50mph (80 km/h), but the average was 45.5mph (73km/h), so that's what they'll take," Mr McKeown said.
"The truth is I'm never going to be happy with how fast I've gone, so I'll always keep trying to do better."
The current record of 42mph (68km/h) was set by a Tesco shopping trolley in 2011 for Guinness World Record Day.
A man has beaten his own record by riding a jet-propelled shopping trolley at 45mph (72km/h) at Elvington Air Field in North Yorkshire.