ARP Rocker Arm Nut - 7/16-20 in Thread - 0.550 in Shank Diameter - 1.200 in Long - Chromoly - Black Oxide - Aluminum Rockers - Set of 16 IH100020 Designed for the general installer

Designed for the general installer and do-it-yourself customer

Chevrolet: Impala 69 - 72 5

0 inch Outlaw muffler and a single 3

3/8" NPT ports

1998-1999 Ford Econoline Super Duty

ARP Rocker Arm Nut - 7/16-20 in Thread - 0.550 in Shank Diameter - 1.200 in Long - Chromoly - Black Oxide - Aluminum Rockers - Set of 16 IH100020 Designed for the general installerA rocker arm adjuster that doesn't require special tools and won't work loose. Threads on the heat treated Perma Loc Adjusters are machined exactly perpendicular to the adjuster bottom. a set screw is also machined flush on the bottom. All of these features help eliminate setting valve lash on a regular basis. ARPs product line contains thousands of part numbers, and has expanded to include virtually every fastener found in an engine and driveline.