looking for roll bar application question

SpareParts said

I have heard something about that but idk how much of a factor it is when you consider a car may race for years with an 8.50 cert cage then later in life say they want to update to a faster cert they typically just build off of the existing cage, I would think if the stress and fatigue were truly a problem they would remove the old bars. Not saying anybody is right or wrong, just a thought.

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I can not find where I seen it. Spoke to a friend earlier today that did some fab work for a while. He told me that the problem with a cm cage is indeed they become brittle, if there is any movement in them at all. He mentioned that he did see something a while back in the SCORE rule book about not using chrome moly in the cab of trucks in certain classes....He also told me that chrome moly tubing is not any lighter than mild steel, when you compare apples to apples. He said that the reason a moly cage is lighter than a mild steel one is because the material is thinner. He priced out some projects for folks, he said that the moly cage, depending on how elaborate, was often more than double a mild steel one, thanks to the tig welding....

For a bracket car he just kinda chuckled when I asked him about using chrome moly....he said it is far cheaper to just use a mild cage and run the half tenth slower from the extra 50 pounds or so that the mild steel cage will bring....