My VW based TD had P165/80R-15 tires on OEM VW “Baja Bug” rims. Same as the tires that came on the VW.
Experimenting with tire pressures, I used ride, cornering and the tread pattern in sand to determine what I eventually ended up with.
Keep in mind, my OEM VW suspension was correctly modified for spring rate front and rear.
I started with 24 lbs per tire rear/22 front…ride too harsh, center tread left deeper pattern in sand, cornering was OK.
I went to 22/18 and things got better in the ride department, more of the tread was meeting the road and the cornering got even better.
I went to 20/16 and the front tires left a great pattern in the sand, rode better, the rear tires left a deeper tread pattern almost even across, but the rear tires started a slight squeal under hard cornering.
I went to 20/14 and it seemed to be great all around. The ride and cornering were good, no more rear tire squeal and an evenly deep tread pattern in the sand.
About a month later, I got to scale the car at a buddy’s race shop. A pound of air in the tires made a 16 pound change in the wheel that got the extra air. I went back to my orgininal 20 rear/14 front and it was the best we could get the car for balance.