I am totally new to big tires and have a question about what I should set the tire pressure at.

2400lbs SBC vega making roughly 550hp. Ladder bars. 31x14 D05 Hoosiers.

What would be a good tire pressure to start at for testing?

I would say 7 1/2

10

^^^^^^ X2 minimum.

exactly

As high as you can go without causing wheel spin.

Yep 10. I’m 8.5lbs @2005lbs 14x32 D05