rotary engine components engine rotary item no 1 part number 4352-11-301 code req c description apex seal carbon 3 mm width apex seal iannetti model engine type 12a year notes 6 1974-85 requires use of competition apex seal springs part #4352-11-304 1974-85 3 mm width 2 spring design requires use of modified springs 1974-85 includes side piece part #1202-11-302 1974-85 requires use of competition apex seal spring part #zr03-11-c04 3 mm width 1974-85 3 mm width 2 spring design requires use of modified springs included 1974-85 includes side piece part #1202-11-302 3 mm width 1986-95 2 mm width ...