The forces of higher rpm and power-adders can overwhelm main bearing caps and fasteners, causing the caps to walk, fastener threads to fatigue, and your main web to crack! Speedmaster™ main cap girdles dampen the harmonics that caused the main caps to move in the first place and effectively tie all five main caps together for enough brawn to produce big horsepower capabilities with a stock block!. Speedmaster™ has designed these main cap girdles to reinforce the alignment of the main caps in high performance applications and counter the limited webbing and weaknesses of those stock blocks.