Yep, I appreciate that, and you're right in everything you've said just then, and I didn't overlook it, but I'm assuming most people fall under one of these two categories:
- Either they're building an FIA compliant cage, which doesn't have that provision. It's black and white in saying no alloyed metals, with no
BS we'll-crumble-under-pressure-when-begged-to disclaimer like what CAMS have done with that provision you've quoted.
- Don't want to spend thousands of dollars going through the certification process...
If someone wants to build a non-FIA compliant cage,
and go to the expense of getting CAMS to approve a 4130 cage, then they must be nuts.
I'm know the FIA is still homologating cages with T45 due to it's reduced requirement for localized heat treatment after welding (pretty sure most
WRC and R2/3 cars run T45 now), but I'm almost 100% sure (though don't quote me) that they won't certify 4130 anymore, due to the known problems with cracking when not properly heat treated post welding. If CAMS in their infinite wisdom want to continue to approve 4130 against the FIA regs which they basically copied in the first, then that's their prerogative, but I'll personally never get in a car with a 4130 cage having seen the catastrophic failures that can occur with them...