dandecicco said:
I know a good rocker needs to connect to the sub frame and pinch seam as all designs and discussions indicate that. But, out of curiousity, why can't some thick (like 3/8 x 5 x 3 or similiar) angle iron just bolt right onto the stock lower rocker pannel and run from wheel well to wheel well?
Even if it went up past the door openings it could be cut to shape. It seemes like it would be strong enough to at least use a high-lift on if not drag accross some rocks and not bend or tweak the uni-body.
Just wanted to know if anyone knows exactly why this is bad to do.
Thanks, Dan
The concept you describe (if I grasp the concept correctly) is much like cutting out the factory rocker panel and welding in rectangle tube for a replacement, but instead scabbing angle iron on the outside of the factory body panels (with no cutting)?
The problem with angle iron is a combination of things. Angle iron offers little resistance to bending (it's beefy, for the weight, but it pales in strength compared to similar weight per foot rectangle tube). The attachment to the factory body panels is not over much surface area (they are thin line and point loads), and it's not tied into the structure of the factory unitary body (it attaches to the skin of the body, the part that dimples and crushes). Another issue reducing the strength of this configuration is the taper between the XJ rocker panel and the pinchweld seam needs to be managed (either taper the long web of the angle iron, or bridge the gap to tie into the standing seam). The last issue is the factory pinchweld standing seam needs reinforcement (how many
Members found this out... too late).
Yes, angle iron can be made to work, but you must keep the vertical web of the angle iron attached for the full length below the doorsill (welded or bolted). In addition to this doorsill attachment, you need to tie in the horizontal web of the angle to the pinchweld seam and reinforce the standing seam at the pinchweld. Combine the 3x6 angle iron under the doors with rectangle tube along the pinch weld seam (1x3 or other) to reinforce the bottom of the door sill torquebox and bridge the tapered body issue, and you will have something that works.
The drawback of this configuration is the angle iron reinforcement does not extend outboard of the door sill, and will not provide much side impact protection. Adding another 1x3 rectangle tube, one that sticks outboard of the door sill angle can offer more side protection (with the added weight penalty).
Does this make sense?
