What spring rate should I set with stock springs and an 8CM camshaft

[1951 Ford F3]

I am having a hard time deciding on valve springs for a Merc rebuild. I just ordered an 8CM camsahft from Delta. The specs are 208 effective at .050 with a .338 lift.

I ordered some Isky 185 G springs, but they are way to stiff. I then ordered a fairly nice valve rebuilt kit, however, the springs tested at 26 pounds installed height and less than 100 at coil bind. Needless to say these are tractor springs.

So, I want to keep the rest of the kit, but need good stock valves that are at least 60 pounds at 2.00 installed height or (1.940)

I saw that Van Pelt has a nice valve rebuild kit and also stock springs that are about 50 pounds at 2.125.

I could just regrind my original valves and reuse the springs

What say yee