Valve Springs for GM847 and 1.6 Rockers?
 

can anyone suggest a good valve spring for the GM847 cam w/ 1.6 rockers? i'm currently looking at the CC987 and CC985 springs. will either of these be enough for this cam? this is for a track car that will be spinning to 6900 RPM. my heads are able to take a spring up to 1.450" OD. any help appreciated. TIA.