Use the heavier springs. Neither one is particularly extreme- - - - -I'm accustomed to running triple spring setups with 300+ pounds of seat pressure on round track race engines. If you ever happen to get into an over-rev situation and float some valves the soft springs might allow some valve/piston contact and bend a few valves. That soft spring pressure might not seal the valves properly under compression, also.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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