in my very limited experience, passion vine does well in sunny spots,... I've seen it doing well in zone 9-10, so it would probably be ok in 8, too? ( http://davesgarden.com/guides/pf/go/53806/ ) I wish I could give you more info... sorry!

Passiflora adores sun and heat so your site should be no problem. Water regularly, deep soaking not shallow. They flower more with fertilizer and some liquid iron.

Enjoy the butterflies - they are the sole food of the Gulf Fritillary!

I don't know about 'Ruby Glow', but my experience with other Passifloras indicates afternoon shade wherever the summer highs go much over 100 F. Good luck! : ]