I am really surprised this didn't kick up

crackedback said
So what happens to all the spot welds in the flexing areas? hmmmm Those flexing areas would have the same "work hardening" problems as well, would they not?

No full frame.... think bean counters and cost. That is another reason they were not full frame. Use the other structures that are required to carry load instead of a full frame. Lighter body means less material.

I've seen NON HP cars have door closing and alignment issues, no broken windshields either. Jack up the right front and see how long it takes to lift the left front... no twisting there. These cars are flex monsters.

Everything is a trade off. Show me a lo-po car that has the spot welds torn out of it from a set of connectors. Connectors make everything a bit more solid.

Exactly!!!

That's what I was talking about earlier too. Yes, you can get fatigue hardening if you make the chassis too stiff. But you can also get work hardening if it's flexing too much. Both can lead to cracks and failures, and the untrained observer won't know the difference between cracks caused by the chassis being too stiff and cracks caused by the chassis being too flexible for the materials it's made out of. That's the problem with Tony's video, he never even considers the increased loads or what that means for increased chassis flex.

And without a finite element analysis based on the loads being applied, no one is going to be able to say with 100% certainty what is right. I know for a fact the factory engineers never considered suspension loads like what I'm putting into my car with my 275/35/18's. Not even close. And I know from my own engineering background that the chassis must be stiffened to handle that load. Have I done the "right" amount of stiffening? Again, even I couldn't say with 100% certainty because I haven't done the structural analysis needed. But I DO know that leaving it stock was not the appropriate answer, even on a car that primarily sees street use. So I'm left with making an educated guess, using torque boxes like the factory did to tie the frame to the rockers. Using subframe connectors to stiffen the body and distribute some of that increased load away from the rockers, so they see loads closer to what was originally intended. Adding a tubular radiator support to tie the ends of the frame rails together, and using forward braces (J-bars) to tie the firewall to the shock towers and the ends of the frame rails, triangulating that entire section. Is that too much? Is it not enough? I can't tell you 100%. I know it was far better than doing nothing, because the increased suspension and torque loads were well above and beyond what the car was originally designed for.