ST 5.0 Series Cylinder Head
• 171cc Intake Ports
• 55cc Combustion Chambers
• 1.940'' Intake / 1.600'' Exhaust Stainless Steel Valves
• 1.470'' Dia. Springs - 125# Seat Pressure
• Steel Retainers
• Assembled, 2/pkg.
  
  
  Cylinder Head Specifications
• Intake Port Volume: 171cc
• Combustion Chamber Volume: 55cc
• Valves: 1.940' dia. x 4.920' o.a.l. Stainless Steel Intake / 1.600' dia. x 4.940' o.a.l. Stainless Steel Exhaust ( 11/32' Stem Diameter )
• Valve Springs: 1.470' Diameter - Open Pressure: 325 lbs.; Closed Pressure: 125 lbs.; Installed Height: 1.900'; Max Lift: .575'
• Spring Retainers: 1.430' 7° Steel
• Rocker Studs: N/A
• Guide Plates: 5/16'
• Valve Seals: 11/32'
• Spark Plug Configuration: Angled
  Facts and Related Components
• Torque Heads: 100 ft-lb. with 1/2' Studs; 70 ft-lb. with 7/16' Studs
• Torque Rocker Stands: 30 ft-lb.
• Torque Rocker Studs: 40-45 ft-lb.
• Intake Gasket: Fel-Pro 1250 (p/n 375-1250)
• Head Gasket: Fel-Pro p/n 375-1011-1 or 375-1011-2
• Exhaust Gasket: Fel-Pro p/n 375-1487
• Head Bolts: ARP p/n 070-154-3605 (289-302ci); 070-154-3603 (351ci)
• Head Studs: ARP p/n 070-154-4005 (289-302ci); 070-154-4203 (351ci)
• Spark Plug Specs: 14mm Thread, .750' (3/4') Reach, Gasket Seat
• Valve Angle: 20° Intake, 20° Exhaust
• Angle Milling: N/A
• Flat Milling: .0060' per cc
• Valve Centerline: 53/119
• Rocker Arms: Ford Stock 5.0 Standard Non-Adjustable Rockers (Ford Motorsports p/n M6564-B351) for St 5.0 Series; Any Ford Roller Rockers with 7/16' Rocker Studs for ST 5.0 R Series
• Lifters: Standard
• Spring Pockets: May not be cut any larger or deeper than 1.550'
• Accessory Bolt Holes are Drilled
• Recommended Intake Manifold: Small Block Ford
• Air Tube: Stock air tube can be used with minor modifications

Emissions Note:

This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART