Terrorists who dubbed themselves the Three Musketeers will be sentenced later for plotting a Lee Rigby-style attack.
Two members of the gang, from the West Midlands, sought out infamous Islamic State supporter Anjem Choudary before they prepared to strike police and military targets on British soil.
They were arrested in August last year after MI5 went to bug the car of Naweed Ali, only to uncover a pipe bomb and meat cleaver hidden in a JD Sports bag.
Convicted terrorists Ali, 29, Khobaib Hussain, 25, and Mohibur Rahman, 33, who served time together behind bars, denied preparing an attack.
They claimed the incriminating evidence was planted by undercover police officer Vincent, the boss of a fake firm called Hero Couriers.
Vincent was cross-examined over 12 days and repeatedly rejected the allegations against him. He also described them in a private message as "the usual bollox".
Jurors agreed with him and, after deliberating for more than 22 hours, unanimously convicted the men of preparing terrorist acts, along with fourth defendant Tahir Aziz, 38, who was found with a large sword stashed in his car.
As they were led from the dock on Wednesday, Rahman shouted out: "I hope you're happy with your lies. Lying scumbags."
The Old Bailey trial heard how the trio of convicted terrorists called themselves the Three Musketeers in an encrypted chat on the Telegram messaging app.
Ali and law student turned trainee gas fitter Hussain, both from Sparkhill, Birmingham, were jailed for joining a terrorist training camp in Pakistan while Rahman was in prison for possessing an al Qaida propaganda magazine which contained bomb-making instructions.
Rahman, of High Lane, Stoke, had connections with other extremists, including Choudary, who he is believed to have visited with IS fanatic Aziz last May while the radical preacher was on bail awaiting trial for supporting IS.
Primark salesman Aziz was keen not to be "left behind" but was only brought into the Three Musketeers plot shortly before the arrests.
The gang had tried to evade secret services and police and even attempted to double-deal with an MI5 contact of Rahman's to extract information.
But the authorities were one step ahead of them with an elaborate undercover operation at Hero Couriers, where Hussain and Ali were offered driving shifts.
On August 26, Ali arrived for his first day at the depot and left his Seat Leon at the Birmingham depot before MI5 moved in to conduct a search and "technical" operation.
They found the JD Sports bag in the footwell, containing a partially constructed pipe bomb and meat cleaver with the word "kafir" - meaning non-believer - scratched on it in readiness for the imminent attack.
An imitation gun, cartridges, a 9mm bullet, latex gloves and industrial tape were also recovered.
The defendants were arrested by West Midlands Counter Terrorism officers the same day.
Jurors were told Hussain had previously handled the same type of pipes used for the bomb on his gas fitter's course and his DNA was on the roll of tape.
Mr Justice Globe will sentence the men at the Old Bailey on Thursday morning.
Rahman, from Stoke, will also be sentenced for two further offences after pleading guilty earlier this year to breaching his licence conditions. It followed his failure to notify police of a change of address under requirements of a sexual offences order and an order under the Counter Terrorism Act 2008.