Quote Originally Posted by joeg View Post
New or old rules I think you can box the feet to raise it. Under the old rules, you need to make certain that the box is welded to a vertical structure and not just sitting on floor shheetmetal.

Multiplanes are expressly allowed under the new rules, but you should still tie it into a vertical structure.

Boxing beats messing with a plugged tube extension, although done properly, that is very safe.
box feet are decidedly legal, but not specifically addressed i the rules, new or old. my concerns are only that there are no well researched rules stating requirements of construction of such a device - if they fail, be it side impact or roll over, the results could be WORSE than being in a car without a cage. same holds true for traditional mounting to plates along existing surfaces, thus the vertical surface rules. the potential for movement is just greater with a box that fails.

I don't want to see them made illegal, particularly in light of the many cars about that have them already and advantages they can bring to overall cage integrity. I just want to see some sensible rules regarding their construction that go over and above the multi-plane and max surface area / linear dimension / plate thickness dimensional limits, as these are all associated with "traditional" building techniques and in no way specifically allow or describe the particular requirements for a boxed foot. the current wording is adequate to claim them as legal, and inadequate to ensure their safe construction.