I've used these flywheel bolts on Fords and Chevys for years with no issues. If you're replacing a clutch its a good time to replace the flywheel bolts, especially if the engine sees high performance use and has some mileage on it. Most engine fasteners should really only be reused 3 times, and in my experience high performance cars go through clutches, meaning that these bolts are removed and installed fairly frequently. Once the engine isn't stock there's no reason to risk using the stock bolts to hold it together.