And, if you weighed enough to need to add a psi or 2, just based upon your weigh, you'de have to be a big guy, who would already have needed to upgrade the suspension, and be pushing double average rider weight/or rider and passenger, 300lbs+
But, again, there are so many variables, and you will not be trying to calculate tire pressure based on rider weight, but rather with correct suspension setup and where and how you'll be riding.
Carry a tire guage, check the psi at stops, make adjustments, try them, repeat, this is the best way, trial and error in Your real riding environment.
You can set it and forget it, but you'll never get the best or safest handling that way, and the psi should be checked before every ride.
90° valve stems work great for this!