Hook’s Collard started race one from 13th on the grid and finished an excellent fourth.
Race two did not go to plan for the Hook driver, as he spun out on lap four when sitting in a podium finish.
This meant he started the final race at the Derbyshire circuit 28th on the grid and produced a storming drive to finish seventh.
Odiham’s Foster finished the meeting with another top 10 finish as he came in eighth.
In his first two outings he had to settle an 18th and 15th finish on a very greasy track.
The two drivers are next in action on the first weekend of the May in their home round at Thruxton.