The Devils turned in a solid team performance with Todd Kurtz leading the way on a 15-point maximum.
The 23-year-old Australian overshadowed his younger brother Brady, who had an impressive debut for the Devils, scoring nine (paid 10) points from his four rides despite taking a couple of heavy falls in his first two races.
Team manager Lee Trigger said: “It was a bit of a worry seeing Brady go down and he wrote off his bike when he came off in heat six. But he used his second bike in the re-run and has gone away happy.
“It is good to have a number one, who can win heat one for us. He and Kyle Newman started off with a 5-1 which set us on our way.
“I thought Todd was superb for us all evening, but generally it was an all-round team effort. They all packed in the points and I believe we have a formidable line-up at home, which is also capable of picking up some points in away matches as well.”
Plymouth: Brady Kurtz 9+1 (4 rides), Kyle Newman 6+1 (4), Jack Holder 8+2 (5), Todd Kurtz 15 (5), Sam Simota 9+1 (4). Reserves: Stefan Nielsen 9+1 (5), Ellis Perks 0 (3).
Workington: Ricky Wells 4+1 (4), Rasmus Jensen 7+1 (5), Kenneth Hansen 4 (4), Mason Campton 3 (4), Claus Vissing 13 (5). Reserves: Adam Roynon 3 (3), Matt Williamson 3+2 (5).