The Silvertop con-rods are really solidly constructed and with bolts weigh in at 506 grams each (with no bearings). The Blacktop was equipped with thinner, lighter and weaker rods which are 485 grams Each individual. The two are easily interchangeable and use precisely the same fasteners for the key bearing https://toyota-4a-ge69811.full-design.com/considerations-to-know-about-jdm-toyota-4a-ge-73942607