I've been checking out the new O.S. 12 TR R-Spec for a while now. So I get ready to buy one, and Tower says, discontinued. I can't seem to find it anywhere. The dealer locator takes me to Tower and a few local shops that don't have them/can't find them either...What happend?

os tz 12, that is what happened, still if you want the r spec, just get the tr and changed the button head to turbo and the cooling head to hyper, and voila, r spec! ah almost forgot add the crankcase body from the tr p turbo.

I'm not sure if they are discontinued yet. Tower listed them as discontinued (they do that when they stop carring something) long ago but they were still available. If you look around you should be able to find an E or R-spec (same thing). OS never showed either one on there site.
Seisick is right about the TR but I wouldn't change the block, only difference is its black. One other thing is the carb is different.

I was only interested because I'd like to be able to compete in a ROAR sanctioned event. However, such events rarely happen, and there aren't engine limits at our track. So..looks like I'll just get a 5 port TR instead.

if i were you, iŽll wait for the tz, chech the thread for the tz, that engine goes hand to hand with the jps and rody according to romuald 31, and stock