frame connectors

famous bob said
no way can a 3 sided, (body thickness piece of metal) welded to the underside of the floor, be as strong as a 4 sided-1/8 wall, 2" square tube stuck in side the rear frame-and cut up into the floor area-and welded the full length of the floor cut-and then welded to the trans cross member. think about it.

You're ignoring how much stiffer it makes the floor pan, and how much these unibody cars base their torsional rigidity on the floor pan. Even the torque boxes make a big difference, and what do they do? just reinforce the corners of the "box" between the rockers, frame and floors. Even the frame rails on these cars aren't much thicker than the floor pan. 16 gauge. That's it. The floor is what, 18 gauge? For the weld-to-floor, contoured style connectors you have to look at the entire structure, which is how the uni-body was made to begin with. Plus for a lot of the torsional calculations the cross sectional area is a more important factor than the wall thickness (same idea as a tubular sway bar), and the contoured style connectors have some areas where the cross section is larger than a 2x2" square tube.

Like I said earlier, neither type of subframe connector is clearly better than the other. You'd need a whole lot of high level, scientific testing to prove one way or another which style was "best", and that's never going to happen. Truly, I think the limit with these chassis' is not the type of connector, but how much the chassis as a whole can be improved by adding any kind of connector. There's a point where it doesn't matter what you do for frame connectors, you could weld in railroad track if you wanted, the chassis wouldn't get better (it would just bend somewhere else). And with these unibody's I think the limit for improvement of the chassis is more important than the construction of the frame connectors. Either style of connector will probably get you pretty close to the maximum amount of improvement you can get out of the chassis by adding a frame connector.