The question no-one was asking

I found a torsional stiffness value of 2,650 lb.ft/degree quoted from the 1963 Pressed Steel Fisher report, in the Porter book. That puts our gain in the range 3.3 - 3.6x. I’ll round that to 3.5x for simplicity.

The same report gives a bending stiffness of 0.040 inches for a 1,000 lbf load placed between the axles. We got 0.016 inches, an increase of 2.5x stiffness.

The above were achieved without glass installed, because of timing constraints. I expect the windshield will give a useful gain once bonded in place.

Below is the setup for the torsion test - rear structure attached to a beam bolted to the floor, load applied to front structure.

1 Like