A group of masked bikers lured a builder to a fake meeting to intimidate him with a blowtorch and an axe.
The five men were trying to terrify the 55-year-old victim into paying £40,000 to his former fiancée, Exeter Crown Court heard.
The man escaped, and was chased for about 500m during the incident in February 2018.
The five gang members were sentenced to a total of 14 years for false imprisonment.
The court heard how the victim was conned into going to a fake meeting with a client at a house on Axtown Lane, Yelverton, but was instead intercepted by the five men as he pulled up at the property.
He tried to drive off but got trapped in a dead end, where a BMW blocked him off. Three men in balaclavas jumped out of the car and surrounded his Fiat before smashing his windows with rocks.
He managed to get out of the car, hitting one attacker and pushing away another, before running to a nearby home where the police were called.
As well as an axe and a blowtorch, officers found pliers, screwdrivers, a hammer, scissors, cable ties, rope, chains, two pillow cases, two cans of petrol, and rolls of plastic sheeting in the back of the group's vehicle.
They had fled the scene, but four of them were arrested on the M5 as they tried to return home.
- Jez Ball, 56, from Totnes, Devon, was sentenced to four years in prison
- David Bird, 58, from Swadlincote, South Derbyshire, was sentenced to two years and four months in prison
- Stephen Cooper, 58, from Swadlincote, South Derbyshire, was sentenced to two years and eight months in prison
- Robert Haywood, 56, from Burton-upon-Trent, Staffordshire, was sentenced to two years and eight months in prison
- Dean Ramsell, 44, from Coalville, Leicestershire, was sentenced to two years and four months in prison
Judge Timothy Rose told them: "This had been planned for at least two weeks - you went about the execution of what amounts to an extremely serious criminal offence of false imprisonment".