This smells of a set-up, but I will bite!
B'ville and Eldora are very close in speed, with a slight edge to B'ville. But, the real issue would be the safety differences between the two. The guard rail at B'ville is dangerous at best, and to add the speed of sprints or the weight of SC cars would create a serious safety concern? The safety features at Eldora are first class. The Big E also always has a Life-flight on the grounds because of the distance they are from a major trauma center.B'ville is along way from a trauma center. Eldora has a catch fence along the front stretch that was designed to withstand the impact of a 1500lbs. car, the catch fence at B'ville is not on the same level.
So, is B'ville to fast, no, USAC boys are the best in the game at what they do. Is B'ville to fast with the safety issues, absolutely!!