It's just not a good match. A lot of the performance comes from the actually wheel width. For instance, a 7.5" wide rim is a *really* nice match for a 205 tire. 225 is still alright but not as good, 235 is OK and 245 is pushing it. A better match for a 225 is an 8.5" wide and 235 would still be VERY nice. With our SHOs we have a limited amount of space so most people just go with 7-7.5" rims with 235 and sometimes 245 tires as a compromise.
The 6 inches of the slicers is grandma width. 6 inches makes for a performance match on a 185 tire. For the SHO, a 225/55-16 is a good tire for the slicers. It's still a grandma rim, but it's cost effective. Any bigger tire is just going to be crap on those rims. If you want to upgrade the performance after that, it only makes sense to do it right and get a 7 or 7.5" wide rim and take your picks of 225 (for 16" rims) or 235,245 (for 17" rims).
Oops, sorry. You were talking about drag racing and I was talking about handling. I know nothing about drag racing. I'll shut up now.
Rick