I learned that valueable lesson again tonight; you get what you pay for. Torque box reinforcements. When you buy the "on sale" house brand, they are all but worthless. At first I just thought the provided bolts were too long, and dug up my own shorter versions.
Turns out the backing plate as well as my floor were just caving in before the bolts/nuts felt any sort of tight.
I mean, I bet I wasnt hitting 20-30 ft lbs of torque on them and ended up bottoming out the threads on the provided bolts before I realized what was happening. Wouldnt you think that plate would be strong enough NOT to bend so that you could torque those bolts to say 40-50 ft lbs thus holding your torque boxes tightly against the bottom of the car? I mean if the whole thing can give that easily, how much added strength is it really giving your upper torque boxes?
Point to this story is if you buy this style of bolt in reinforcements, do yourself a favor and throw away the cheap long backing plates and cut yourself some thick plates that wont cave in when a skinny kid like me tightens down bolts with a 3/8 ratchet. Now I get to spend more money on thick metal plate and redo these PITAes.
End rant.
Edit: For the record, there are also no torque specs anywhere in the installation instructions. Might be handy to know.