Originally Posted by saxman
we've been talking on the california sol board about the possiblity of using an expanding foam injected into the frame rails on our cars. This is a rather common modification among the old ford mustang owners... basically consists for using a two part expanding foam thats meant for chasis reinforcement being applied into the hollow frame rails, reinforcing them from flex. On the del sol's especially, the flex that causes the problems is from the front to the back of the car, not side to side, so all of these pillar bars, floor braces, etc are worthless
also, keep in mind adding braces isn't necessarily better. I ran at a test and tune day at the track(autox, not drag) and was consistently running about a second and a half faster WITHOUT a rear strut tower bar than with it in.