STS BR 7 273 Series Cylinder Heads
• 273 cc Intake Ports
• 72 cc Combustion Chambers
• 2.250 in. Intake / 1.614 in. Exhaust Valves
• 1.350 in. Dia. Springs - 180 lb. Seat Pressure
• Steel Retainers
• Assembled, Pair
  
  
  Cylinder Head Specifications
• Intake Port Volume: 273cc
• Combustion Chamber Volume: 72cc
• Valves: 2.250' dia. x 5.200' o.a.l. Intake / 1.614' dia. x 5.230' o.a.l. Exhaust ( 8mm Stem Diameter )
• Valve Springs: 1.350' Diameter - Open Pressure: 430 lbs.; Closed Pressure: 180 lbs.; Installed Height: 1.810'; Max Lift: .700'
• Spring Retainers: 1.290' 7° Steel
• Valve Seals: 8mm
  Facts and Related Components
• Torque Heads: 11mm STUDS - 85 ft-lb. WITH OIL / 8mm STUDS - 26 ft-lb. WITH OIL
• Torque Rocker Studs: 22 ft-lb.
• Intake Gasket: Fel-Pro p/n 375-1208-3 (.060), GM p/n 809-19172113
• Head Gasket: Fel-Pro p/n 375-1185-041 (4.175 bore) or GM p/n 809-12582179
• Exhaust Gasket: Fel-Pro p/n 375-1440
• Head Studs: ARP p/n 070-234-4319 (under cut studs)
• Spark Plug Specs: 14mm Thread, .750' (3/4') Reach, Gasket Seat (NGK R5671A)
• Valve Angle: 12°
• Flat Milling: .0060' per cc
• Dowell Shift: Standard
• Pushrod Slots: Standard
• Rocker Arms: LS7 style
• Lifters: Standard
• Intake Manifold: LS7 or Equivalent
• Valve Centerline: Standard
• Spring Pockets: 1.350' out of the box, May not be cut any larger or deeper
• Accessory Bolt Holes are Drilled

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