[Doug Clark]

Bill,

A good part of this exercise from my point of view was to do the whole thing "my way" for what I've thought were the important first principles.
For me torsional stiffness (I worked to a goal of 10,000lb/deg in the model) and occupant protection were the primary goals and I spent a lot (probably too much) of time working on structural analysis to achieve these goals (I hope). The computer model shows the completed frame coming in at 127kg (the last time I weighed it, it was about 10% less than what the model said it should have been) , the completed car I expect to way about 950kg.