TA offers replacement main bolts that are far superior in strength over OEM main bolts. These high performance main bolts are forged from 8740 chrome moly and include such desirable features as generous under-head radius and rolled threads for the utmost in reliability. These bolts provide a normal rating of 170,000 psi, and are 100% less prone to fatigue as compared to stock bolts because of the unique process of rolling the threads after the heat treating process.