Kier Armstrong emerged the fastest at the end of Friday as he stormed to a best lap of 1min 30.677secs to beat Franco Bourne by just 0.015 secs.
Aaron Silvester was third in a second session which was considerably quicker than the first, with Seth Crump fourth and Kam Dixon fifth.
Pirelli National Junior Superstock Championship with MotoNovo, Brands Hatch, combined practice.
1. Kier Armstrong (Lincolnshire Racing Mulisha) 1min 30.677s
2. Franco Bourne (Marvel HCL Motorsport) +0.015s
3. Aaron Silvester (A&J Racing) +0.055s
4. Seth Crump (Seeeeeth) +0.261s
5. Kam Dixon (RK Racing) +0.405s