lol, is that an extra 6 in there?
Even if it is, a 60 profile on a 335 tire with an 18 inch rim would be a big dia tire. If you want straight line traction, ditch the 18's and get a 15" rim out back. Even a 265 drag slick on a 15" rim will probably grip better than anything on an 18" rim for straight line launch.
The reason is that the sidewall has to be able to flex a certain ratio to the traction patch of the tire to provide optimal grip under parallel loading (if I'm wording this right). If you watch slow motion drag racing shots, you can see their sidewalls bunch up on launch, this is good. A tire on an 18" rim cannot do that because the sidewalls are made too stiff. Of course, tires that provide superb traction from a dig can make it handle like an oil tanker in the corners.