IE Tall Boy Billet Steel Main Caps for BMW M5x and S5x

IE Tall Boy Billet Steel Main Caps for BMW M5x and S5x


Item #: IEBEBA2


In high horsepower engines the block can flex resulting in abnormal bearing wear damaging your crankshaft and other high dollar parts in your block. By installing billet main caps, you reduce the flex of the block resulting in a stronger bottom end. When billet main caps alone are not enough, Integrated Engineering offers our Tall Boy main caps to be used with a crankcase bedplate/girdle. These main caps are special because they are designed to work with a crankcase bedplate/girdle. Typically, the installation of those products requires machining small spacers, which go between the main cap and the girdle, bringing it up to the same level as the pan rails. What we have found is these spacers are very difficult to machine to the correct height. Even when done with extreme care, this compromises the installation and results in a warped girdle. Our solution to this problem is our Tall Boy main caps. These stand slightly proud of the pan rail as they come out of the box. They are then machined level with the pan rail, resulting in a perfectly flat surface for the installation of your bedplate/girdle, and the most rigid foundation for your crankshaft possible. In addition, the large profile and high strength material is much stronger and stiffer than the factory main caps. Help protect your expensive investment with these Tall Boy billet main caps.

The Tall Boy BMW M5x and S5x main caps are carefully crafted, in-house, from 1050 steel. They provide extreme rigidity to the main bearing and crankshaft, and a flat foundation for a bedplate or crankshaft girdle installation.

Crafted from 1050 steel
Coated with black oxide for resistance against corrosion
Added strength to bottom end for high horsepower
No spacers required when used with a girdle

If you are not using a girdle, please purchase our standard BMW M5x/S5x billet main caps.

Requires machine work including align bore & hone for fitment.