These are forged rocker like was available with the car, but these come in a 1.5 ratio. The stock rockers came in 1.3 ratio. Going to 1.5 ratio gets you more lift on your valves meaning more air in and out of the engine. More air in and out of the engine means MORE POWER! These are a cheaper alternative to roller rockers. Some racing classes don't allow roller rockers either, this could be a way to get the extra lift without technically breaking the rules. Isn't racing all about finding ways to get an advantage within the rules?