RS Motorsport :: Classic Speed Restored

I have an F2000 Van Diemen that we did the head on and fitted a Kent FR32 cam kit to. On the weekend before my second race it popped No.1 and 4 inlet and No.3 exhaust valve stem seals. Pushed them back down and clipped on and now it is running fine...albeit only in the garage. Anyone heard of this?..I also fitted 2mm oversize Burton valves at the same time.
Thanks
R

Its a controlled class Roger..you aint supposed to do that..but as I use it for sprints and hillclimbs and Confedration Against Motor Sport wont lift the cut off years..I am in no mans land..I can see me in 30 years time still in the same place...
R