[Bob]

If they are the Motorsport (Ford Racing) 1.72 ratio roller rockers they are a good upgrade. They will reduce friction in your valve train, and will also add about .015" lift to your stock cam. While not a huge performance increase, it's worth a little horsepower, and every little bit helps. As posted above, you will need to get some new valve springs to go with the rockers, as the stock ones wont last long with the added stress. Crane makes a very good set of performance springs, retainers and keepers that come in a kit to fit the stock heads. I ran 'em when I had stock heads with the same rockers your looking at.