na that Isky Todd has and the 928 go in at around 1.950 and are around 145 seat and 345 open just depending Indy always sent out 928's and we would shine the retainers and locks in race engines--the 928 could not keep up with a 650 solid or a hot 590 with lots of RPm so Todd found this Isky that works much better in race application ask him part number I can't remember 145 345 or little higher works with lite retainers like Titanium or lite steel Comps