Note: 1.7 ratio rocker arms with 7/16" adjusting nuts. The 1991 and later Gen V and VI engines require the installation of 99152-16 7/16" rocker arm studs (no machining required) and factory pushrod guideplates. For applications with over 480 pounds open valve spring pressure, the cylinder heads must be machined for the installation of 99157-16 7/16" rocker arm studs and 13650-1 pushrod guideplates. Street/Strip Rocker Arms 13744-16$251.20 Street/Strip Rocker Arm 13744-1$15.70 7/16" Rocker Arm Studs Set/16 99152-16$99.20 7/16" Rocker Arm Studs Set/16 See Product Info 99157-16$64.00 3/8" Pushrod Guideplates Set/8 13650-1$68.80