which size slicks

yes, they will work as slicks but for a high hp maybe in the 450+ area i would just use a dedicated pair of slicks for the track, the good thing about Nittos is they are not as soft as some drag radials so they are lasting guys around 10K to 15K and they don't pick up and toss as many rocks and garbage at your quarter panel. Also i fully expect these tires to last 10K on my ride where my BFG T/A's were bald in about 6K. If you like to do burnouts, and fishtails go with street tires, if you like to leave the light like you were shot out of a canon go with a drag radial.