Well, I don't know anything about the Tohatsu, but when I raced Mercs and Konigs, I found that I gained speed if I waxed the deck, vacuumed out all the dirt and gravel, mopped up all the coagulated oil, went on a diet and dropped ten pounds, shaved my arm hairs, and drove with my mouth closed, but then, I've had a few beers, so don't trust me.