I put some Pro Line (Gladiators/rear and directionals/front) on my Traxxas Nitro Sport. I'm practicing on a clay oval track at the LHS. They really hook up well except when the track is wet and then I'm sliding. An experienced racer told me this weekend I needed to use foam tires for the oval. I asked around and nobody at our track was familiar with running foam tires on the nitro cars for the dirt tracks. Do I need foam tires and if so where can I get them to fit the Traxxas Nitro Sport?