Our Dart Windsor bare block features four-bolt main caps on crankshaft journals two, three, and four. As you shall see, the outer main-cap bolts are splayed and enter the block at an angle for enhanced strength. The Dart casting is far more robust than a stock or Sportsman block in many critical areas, particularly the support webbing around the main journals. This block arrived with a 4.125-inch bore ready to go. We'll need to install freeze plugs and cam bearings to begin.