Aluminium AC Cobra Chassis

[albanycobra]

I would question your test rig in that the pivot point is below the chassis at front and therefore as you apply load that you are not going to get a true torsion only result. If you were to break down the chassis to simple form the lower plane of the chassis is simply being twisted as its at close to the pivot height, but the upper plane of the chassis is being subjected to a parallelogram type load. If you were to raise the front pivot point you might find you get even higher test results than your current readings as many chassis simply have heavier material in the lower frame rails which would now be subjected to the parallelogrm effect as well..

JACMAC you need to read the NCOP12.LT (National code of pratice) test procedures.. There you will find that the machine in question is set up and tests the chassis exactly as per Government guidelines. Yes they have pictures.

http://www.infrastructure.gov.au/roa...s_3Feb2006.pdf

Maybe the machine does not make sense but that is how they want the chassis tested. My guess is they started like that and now keep it the same so apples can be compared with apples.