What is 6 bolt main caps?

Six bolt main caps are a type of engine main bearing cap used in high-performance or racing engines. They have six bolts that hold the bearing cap in place, which increases the strength and rigidity of the engine block. As a result, six bolt main caps provide better support for the crankshaft and reduce the risk of bearing failure at high RPMs and high horsepower levels. Six bolt main caps are typically made of high-strength materials, such as forged steel or billet aluminum, and are often installed as an upgrade to standard four-bolt main caps. The use of six bolt main caps is common in high-performance engines, such as those used in drag racing, circle-track racing, and other forms of motorsport.