Johnny Garness shot to the top of the opening practice timesheets as he beat Amanuel Brinton to the best lap by 1.634s.
Carter Brown was third quickest, just ahead of Rhys Stephenson with Matthew Ruisbroek fifth.
Honda British Talent Cup, Thruxton, FP1:
1. Johnny Garness (MLav VisionTrack Academy)
2. Amanuel Brinton (Mortimer Racing/Victoria House Academy) +1.634s
3. Carter Brown (MLav VisionTrack Academy) +1.705s
4. Rhys Stephenson (Rocket Racing) +1.775s
5. Matthew Ruisbroek (Microlise Cresswell Racing) +1.894s