I was handling by shobu zukiri raptor katana and thinking about how robust and strong it was. It has some pretty heavy duty dimensions 13" grip, 30" blade , 7.6mm thick and 2lbs 11oz weight. I was wondering if period swords had similar dimensions or if they were generally smaller and of slighter build. Also in terms of strength and cutting ability were they similar or are modern swords so much more capable. I would assume modern swords are superior but how much more?
The swords were generally smaller, because the japanese people were smaller. That's not to say there weren't large ones made. I've seen 300 year old tanto that was 3/4" thick (perhaps they were ancient "stridersama" family

Geometry varied from period to period and smith to smith, as did depth of the sori. One thing I've learned about japanese swords is there seems to be an exception to every rule.
Modern steel and heat treating are vastly superior to what smiths used in the past- which is point of contention for many a cool-aid drinker. They did the best with what they had, and did it very well. Remember, I'm not speaking of craftsmanship as I think some of the old swords still haven't been matched ( ofcourse that's my opinion based on my artistic taste)
Take a look at this site; http://www.nihontoantiques.com/
and find other stores that sell authentic nihonto, most give dimentions.