Structural Foam for chassis stiffening

Absolutely,,,,,I appreciate everyone's input but can't contain my eye rolls & face palms after reading from the misinformed and self-identified "experts" preaching fire and brimstone,,, lol.

Moving on:

This method of quantifing torsional rigidity seems reasonable.

1. Level car on 4 stands with tires off
2. Add Ballast to left rear corner to allow removing stand from right front.
3. Measure chassis height at right front and zero dial indicator
4. Add known mass to unsupported rf (F) and record deflection(d).
5. Measure distance to nearest side stand(L)

Torsional rigidity is founder by finding the torque applied to the chassis and dividing the angular deflection.

K^2 = F × L/tan(d/L)

Repeat test for the other side.