Fixes for a flexy flyer?
 

I have a 78 911SC that was converted in germany from a Targa to a convertible in 1982. I am currently in the process of restoring and up dating the car. While to car is in pieces I thought I would try to stiffen up the body some if I could.

Does any one know of successful techniques to stiffen the center tub of a 911? I know there is a guy that make a kit to stiffen up 914's along the inner rockers. Does anyone have a kit like that for 911? What about seam welding the floor pans and the inner and outer rockers?

I already have a roll bar that ties into the logitudianls and a front strut brace.

The car is a street driver and will not be used on the track. It is getting an upgrade to a 993 Varioram motor and coil over suspension as well.

Does anyone have any suggestions?

May want to start here: http://forums.pelicanparts.com/porsche-911-technical-forum/259557-structural-reinforcement.html?highlight=reinforcement

Seam welding won't hurt, but I have yet to drive a 911 that has been treated in such a manner and therefore cannot say with any certainty to what degree it would help.