They were among five people in a yellow Skoda Fabia which crashed on Bromley Lane, at around 8.50pm on Tuesday.
Two others, a teenage boy and a teenage girl, are in a critical condition in hospital.
The three young people killed were pronounced dead at the scene, which was near the junction with Standhills Road.
A police car was nearby when the crash happened but West Midlands Police was today unable to clarify whether it had been chasing the Fabia when the crash happened.
The force previously said officers had seen the vehicle but not spoken with the people inside or pursued it, before changing the statement to say "it is not known if there was any interaction with the Skoda" and that the role of the police car is being investigated.
A police car was pictured being removed from the scene on Tuesday night on a low loader.
The families of all of those involved have been informed. The road was closed overnight, but has now reopened.
Devastated family and friends visited the scene this morning to lay flowers and pay their respects. One floral tribute read: "I love you with all my heart. I couldn't darest think how much people would be missing you."
More tributes said: "RIP brother. Never forget our memories. Rest easy. RIP Lucy you will be missed by us all."
While another added: "Rest easy my beautiful best friend. Grew your wings too early, I will miss and love you so much."
Neighbours and residents in the area of Bromley Lane have spoken of their shock after the tragic accident. One resident, who wished to remain anonymous, said: "It is so sad. We heard all the sirens and flashing blue lights last night. It's really not good.
"It's just horrific, so awful for their families."
Simon Mahal said: "The only thing I heard was a big bang and I shouted to my daughter to see if she was OK. We opened the door and I did not see the car at first, I had a quick look around and then my daughter pointed out the car.
"We went over to see if they were ok, but the police came and we moved out of the way. The emergency services were there for a long time and there was lots of them – they closed the road."
Another resident said: "We didn't see anything happen but we heard a massive bang – I looked out the window and saw the car in the tree. We ran down to see if there was anything we could do to help but the police were there in seconds so we let them carry on.
"The emergency services were here for hours – they cleared the road at around 5am on Wednesday.
"It is awful and they are only teenagers, I can't believe it."
Christian Evitts added: "All we heard was the bang and then we saw the police. By the time we got out there the police were already there. The police told us to go back into the house. They were here for a really long time.
"They were still clearing the road this morning [Wednesday]. They were removing the lamppost this morning. It's terrible what has happened."
Sergeant Dean Caswell, who is leading the investigation, said: "This is a tragic time for the families of those involved, and we have specially trained officers who will be supporting them through the difficult time ahead.
"The investigation is at a really early stage, and we're trying to establish exactly what happened and why.
"I'd urge anyone who saw the Skoda driving in the area last night, or who may have captured anything on dash-cam footage, to get in touch with us as soon as possible."
West Midlands Ambulance Service was also at the scene, sending six ambulances.
A WMAS spokeswoman said: "Crews arrived at the scene to find a car had hit a tree, with five patients involved.
"Sadly, it soon became clear nothing could be done to save the driver of the car, a man, and he was pronounced dead at the scene.
"Despite best efforts of staff, two teenage girls who were back seat passengers in the vehicle were also confirmed deceased at the scene.
"The front seat passenger, a teenage boy was treated for life threatening injuries at the scene before being conveyed on blue lights and sirens to the Major Trauma Centre at Queen Elizabeth Hospital for further treatment.
"The final back seat passenger, a teenage girl, was treated for potentially life-threatening injuries and was also conveyed on blue lights and sirens to Queen Elizabeth Hospital in Birmingham for further treatment.
"Our thoughts go out to the families of all those involved at this time."
Anyone with information is asked to get in touch with the police via Live Chat at west-midlands.police.uk, quoting log 4469 of October 13.