Pictures more from the side of tire, would better see the sidewallbulb.

Goal of determining pressure is to get a deflection so heatproduction a cycle, that wont overheat the tirematerial.

Knowing this you can also measure the goal directly.

My estimation is that with 100% used of loadcapacity for the pressure the tire deflects 20% of the free flexible part of the sidewall. With 90% used about 15%

Your section hight is 7.12 inch, I calculated that for your sizes.

Free flexible part is about 1 inch less, 0.5 inch for the part in the rimmedge, and 0.5 inch treath.

So 6.12 inch free flexible

20% of that 1.224 inch.

15% is 0,918 inch.

Lesser deflection then 0.9 inch gives discomfort, to my opinion.

You have a nice flat waterlevel garage-floor, I see on the pictures.

Most acurate way is to measure first from bottom rimmedge to top of tire.

Second from top rimedge to the floor.

Difference is the deflection.

You will see that if you pump up all 4 tires to 50 psi, that deflection is different for all 4 tires.

Can even be that deflection rear left is higher then RR, and front FrR more then FL.

More deflection at same pressure means more weight on tire.

So you can use the tires as a not that acurate weightscale.

My expectation is rear lesser deflection then front, if car is empty, because less weight on rear then front.

Also made spreadsheet for that, but only in Dutch, but will add 2 pictures

On those I measured from top ring in the centre, to the ground, and bottom of ring to the wood I pkaced on top of treath.

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