body/windshield and steering flex

Previous owner had the center console out. He liked the extra room it gave him, had removed the AC years ago and didnt care about a radio. When I drive the car as stated the suspension has basically zero travel as I've mentioned before. So it rides like a skateboard and every bump is jarring. The suspension issues aside (We're talking about them elsewhere), the steering, dash and even windshield oscillate sideways over the bumps. I think the console being bolted back in place would help, but I do not think they are capable of eliminating this flexion, as I can get some twist and flex in that piece itself using manual force.

So I am seriously considering a brace from the under dash support beam down to the tunnel and behind the console. I think this would stiffen the whole structure. The plan is to make it a bolt in piece so it is removable for ease of access under the dash (on my back of course...lol) and bolted in place, yet heavy duty and as rigid as if I'd welded in a heavy brace.

Has anyone done this? Anyone felt the need?

My car had this same problem and I had the console installed.  The thin section that made up the console face wasn't enough to do much good.  I plan to fab a much heavier brace for that area and add additional bracing to the steel frame that is behind the dash.

The fiberglass firewall is supposed to be anchored to the cowl to form a boxed structure, but mine wasn't.  That may help a little.  What is needed, in my view, is a steel sub structure under and bracing the cowl area.  I hope to go in that direction.

I had originally thought that the chassis was flexing, but after getting a good look at it, I've changed my mind.  The Sebring chassis is a hybrid of a perimeter frame and a backbone chassis and should be fairly rigid.  I plan to try some torsional twist tests when I get the chassis reassembled.

BTW - The movement you described is called cowl shake if you're in the US and scuttle shake if you're in the UK.  It's pretty common in convertibles.

I agree hotrod, I've felt it before in other convertibles, but not to this extent. Right now my plan is a triangle based brace behind the console with 1/4" steel. I imagine the brace will look somewhat similar to a one of the little metal pieces girls played a game of "Jacks" with as a kid. Triangulation provides great strength and can be done with minimal weight. I'll give it some thought as I take measurements, but I think it should be an overall easy fix.