Thanks. Wouldn't have expected that based on the FSM data I have.
The OP can look at Melling VS-150 or Sealed Power VS-510 for a stock replacement spring. 80-90 lbs seat pressure at 1.650" installed height. Coil bind at around .450" lift if installed height is 1.65".
That is the problem with a stockish SBM springs... coil bind comes pretty easily, too easily for any cam of consequence. So a stiffer spring is needed with fewer coils or thiner wire to get a higher lift w/o getting too close to binding. And that leads back to higher seat pressures. I personally would not worry over 120 lbs seat pressure if the spring rate is not too high.
Melling VS1011 is a $2 spring for which coil bind occurs at about .485 lift with a 105-120 seat pressure and a 232 lb/in spring rate. That might work for the OP if the stock springs do not.
https://www.melling.com/wp-content/uploads/2017/03/valve-springs-identification-chart.pdf
