Stock stamped steel rocker arms are not durable enough to handle the more aggressive loads of current performance camshaft profiles and valve springs.
Ratios will also vary considerably on stock rockers from one to another, that coupled with the added heat and friction of the stock type pivot robs power.
Scorpion Racing Products rocker arms are fully CNC machined for ratio accuracy and strength. The roller bearing centerless ground fulcrum and roller tip lowers friction and heat and subsequently increases Horsepower!