I just bought a cam with about a .700 lift I was wondering what valve springs I should use? The afr ones that came with my heads are only good to .680

 

Ask the company you got the cam from.

 

The above is good advice. If you expect anyone to take an educated guess though, you should post the complete cam specs, supporting components used (especially rocker ratio), valve sizes, and desired/expected rpm range.

Rich

 

264/271 685/656 108lsa
jesel sportsman rockers 1.6
crower hippo solid lifters
comp cams hardened pushrods

valves are: Intake Valve, 2.080" x .050" long, AFR #7018
Exhaust Valve, 1.600" x .050" long, AFR #7057

rpm range will be like say 7200 rpm max and not likely under 4800
converter is a 5200 ati 8" race converter in the th400

 

Mine has K-Motion springs. I don't which ones.

 

Something in the low 200's on the seat and mid 500-600# open ought to be good.

Rich