Police have named the second teenager who died following a fatal crash on the A14 on Thursday 24 January.
It happened on the eastbound carriageway of the A14 at Bury St Edmunds just before 9pm.
Two cars - a silver BMW and a red Ford Fiesta - were seen on the road when the BMW left the carriageway and collided with a tree.
The driver of the car, 19-year-old Adam Weller from Weeting in Norfolk, was pronounced dead at the scene.
The passenger of the car, 16-year-old Macauley Clements from Ixworth, was seriously injured and was taken to Addenbrookes Hospital but died on Friday 25 January.
The 20-year-old driver from Bury St Edmunds of the red Ford Fiesta was arrested on suspicion of dangerous driving and has been bailed.