The sportsmans are the best for racing to give you the height at a light weight.
In a std. radial tire, there isn't much available that's 27" tall anymore. 10 years ago there would be a ton of 75 series tires, but they don't make too many nowadays.
To get 27" tall with a 70 series tire, it has to be 215 wide. The real problem with this set up is a 27in radial tire is nearly 30lbs each.
By going with a 25" tall tire like a 195/60 you can save nearly 20 lbs for the pair.
The 205/70 is 26.6" tall and mid 20's for weight so that might be a good compromise.