[Beertestr]

also my car is showing signs of massive frame twisting on track
aka
cracked the pan hard drop down brace twice

Do you have the panhard bracket tied to the opposite frame rail? Maybe you have binding issues too.

Like any good project you have to start with research.
what do you have and what do you want?

this unassuming chart unlocks the puzzle

What, no Excel sheet... amateur.. This looks very similar to the design sheet I did when figuring out my home brew IRS and new wheels for my 53 F-100.

Nice work for sure on the frame mods. Your engineer friend exercises good judgement. I will be interested to hear if the extra tire is helping or hurting on the AutoX. A friend of mine went to split widths on his Camaro for AUtoX, and the car did not turn as well. THe car became less balanced,and understeered more on turn in, but he was able to get on the throttle earlier.