Should i foam it ??

What I found out, was the only function it performed was holding the foam in place. It was not structurally attached to the boat

Umm, I'd be curious as to who said those bulkheads, or wood frame between the stringer provided no structural support. ??? I could be windtalk'n here but I think they are suppose to help minimize flex as well as adding support to the stringers. Of course, I'm no engineer and I haven't stayed at a holiday inn express lately, so I could just be talk'n out my whazoo ::)