Hub has two .250" dowel pin locating slots in it for a starter hub or fuel pump/oil pump drive mandrel to be run out the front of it if needed. This hub also can be used to help the racer build a support for their engine such as a Pontiac or Ford where sometimes a manufactured crank support is not available off the shelf.
Hub measures 2.300" from pulley surface to bearing shoulder, overall end to end is 3.200". Bolt flange is 1.00" thick from pulley surface to bolt mounting surface.