If I am not mistaken, I think they are 8". But you can definately run 245/50/16, because that is what I run on my Sport rims. It may take the tire guy a little bit to get it on because it fits the width of the rim like a glove. IDK if you can go any wider or not.
'97 Laser Red T-bird w/ Option66S - 125,000 miles, stock except for 3.73s Best ET 15.6 @ 88.3 '94 Electric Red T-bird LX V-8- 212,000 miles- SOLD 2005 Ebony Black Excursion Limited 6.0 Diesel STUDDED
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- Henry Ford
"Opportunity is missed by most people because it is dressed in overalls and looks like work."
- Thomas A. Edison
You can definitely run a 245 or even a 255 series tire on the 16x7 MN12 wheels (Sport, SC, and 7-spoke XR7 wheels). Heck, I actually have a set of 28x11.50-16 ET Streets on a pair of the 7-spokes for my XR7. I wouldn't go quite that wide on a street tire though.
I ended up with 245/50-16 and the fender gap isn't too big plus it bumps up my gear ratio to about 3.40 (from 3.27) due to the smaller radius. The 245's give awesome grip (summer tires) at the track as you can see from the lead i got on the turbo 240 i was racing on the weekend (although he did end up beating me by 1.5sec ET though lol)