The youths, who cannot be named for legal reasons, left their victim seriously hurt following he brutal attack in Monument Street on February 1 this year.
Today the pair, who were 16 at the time of the attack but have since had their 17th birthday, were jailed.
Peterborough Crown Court heard how one of the youths smirked as he plunged the knife into his victim.
Claire Matthews, prosecuting, told the court: "On the evening of Saturday, February 1, the victim went to purchase drugs from one of the defendants in the city centre. He (the victim) had received text messages saying the defendant had stock.
"He went to meet the defendant at Monument Street.
"He saw the first defendant with another youth, who was the second defendant.
"There was a dispute of some kind, and the first defendant produced 'a large Rambo style knife.'
"He was then stabbed in the face by the first defendant, and trapped against the wall and punched by the second defendant. He was then stabbed multiple times by the first defendant."
Covered in blood, the victim managed to crawl to a near-by house, where he was given first aid and an ambulance was called.
He was taken to Peterborough City Hospital, where he needed a blood transfusion after losing 'a significant amount of blood', after suffering seven stab wounds, with his chest, face, arm and leg all injured.
While in hospital he was able to pick out the knife-man in an identity parade, while a few months later, in June, he picked out the second youth in another parade.
When arrested, both youths made no comment in interview.
The victim told police that the first defendant 'smirked and smiled' as he plunged the knife into the victim's body during the brutal attack - although the second defendant 'looked scared' when he saw blood spurting out.
The first defendant also admitted leading police on a high speed chase through the streets of Peterborough after stealing a car on January 2.
He had stolen the keys of a Renault on New Year's Day, driving the car away from the victim's home. The following day he was spotted in the stolen vehicle on Bourges Boulevard by police, and started a high speed chase - reaching speeds of up to 70mph in a 30mph zone.
His car eventually came to a stop, and after initially running from the scene, he surrendered to police - but then told officers he didn't care he had been caught and 'I'd do it again and next time I'd ram you.'
He also admitted stealing a bike from Peterborough Railway Station this summer.
Defending the first defendant, Mark Shelley said: "He has been in custody since his arrest, and during lockdown was in his cell for 23 hours a day - this would be hard for anyone, let alone a 16 year-old."
Gavin Irwin, defending the second defendant said the youth wanted to gain an apprenticeship following his release from custody, and was am intelligent young man - although there was an 'underlying lack of maturity.'
Judge Enright jailed the first youth for seven years for the stabbing, and gave him a 12 month detention and training order for the driving offences, to be served consecutively. He was also given a two year driving ban, with an extension period of three years and four months, to take into account his jail sentence.
The second youth was given a four year custodial sentence.
Both youths pleaded guilty to one count of wounding with intent, with the first youth also pleading guilty to possession of a knife in a public place, dangerous driving, an aggravated offence of taking a vehicle without consent, driving otherwise in accordance with a licence, driving without insurance, failing to stop, and theft of a bicycle.
The Peterborough Telegraph applied to have reporting restrictions lifted to name the two youths, however Judge Enright rejected the application.