Tariq Khwaja's and Venelin Mihaylov have both been locked up after police dogs found the cannabis in Khwaja's car after the pair were stopped by officers on the M6 near Stafford.
The search came after the pair were spotted loading a large amount of the drug into the car at Khwaja's home, where a search later revealed cannabis plants behind a false partition wall in an upstairs bedroom.
Khwaja, aged 45, was jailed for nine years at Stafford Crown Court, while 33-year-old Mihaylov, who was said to have played a lesser role, was jailed for 15 months.
Both entered guilty pleas before their trial was due to start on April 9.
The court heard that officers stopped a black Vauxhall Insignia being driven by Khwaja near Junction 14 of the M6 northbound at Stafford on February 13 last year.
Mihaylov was in the passenger seat after Khwaja, who was employed as a gas fitter, was given the hire car by his employers.
Police dogs searched the vehicle at Doxey, near Stafford, and found 'skunk' cannabis worth £263,348 in a large cardboard box marked as ‘fragile’ and two laundry bags.
The box contained 10 packages of professionally heat-sealed plastic bags with an inner layer containing almost 10kg of cannabis, with an estimated street value of £100,000.
One laundry bag contained 7.9kg of cannabis, with an estimated street value of £80,000, while the other bag contained just over 7kg with an estimated street value of £70,000.
Deals of cocaine were also discovered in the car.
Both men’s addresses were then searched and at Khwaja’s house officers found a professional cannabis working ‘grow’ behind a false partition wall in an upstairs bedroom.
Twelve healthy cannabis plants were growing beneath lamps, with a yield valued at £12,000.
A further £3,464 in cash was seized from Khwaja, whose fingerprints were found on a plastic pot and a black bag found in the rear of the car.
Messages found on Khwaja’s mobile phone revealed that he had been street dealing both cocaine and cannabis from as far back as January 2015.
Khwaja, of Parkhill Road, Sutton Coldfield, was sentenced for possession with intent to supply cannabis and cocaine, conspiracy to supply cocaine, and producing cannabis.
Mihaylov, of Broome Avenue, Great Barr, was sentenced for possession with intent to supply cannabis.
Sentencing on Wednesday, Recorder Coke described how Khwaja had been involved in three separate drug dealing businesses.
He detailed the effects that his drug dealing and others like him had on users, their families and society.
“These were serious offences and therefore deserved a serious sentence." he said.
Detective Inspector Lesley Fowler, of Staffordshire Police, said: “This was a significant operation involving the movement of cannabis and other drugs across the West Midlands region.
“We’re glad that Khwaja and Mihaylov will now serve time for these offences. We are working hard with our colleagues from West Midlands Police, and other Forces, and will not tolerate offenders coming into Staffordshire to peddle drugs.”