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STS -18X Series Cylinder Heads68cc Combustion Chambers Spread Exhaust Ports 100% CNC Ported
- STS -18X Series Cylinder Heads
- Spread Exhaust Port
- 254cc Intake Ports
- 68cc Combustion Chambers
- 2.140'' Intake / 1.600'' Exhaust Valves
- 1.550'' Dia. Springs - 240# Seat Pressure
- Titanium Retainers
- Angle Plug
- Assembled, 2/pkg.
Cylinder Head Specifications - Intake Port Volume: 254cc
- Combustion Chamber Volume: 68cc
- Valves: 2.140' dia. x 5.290' o.a.l. Intake / 1.600' dia. x 5.300' o.a.l. Exhaust ( 11/32' Stem Diameter )
- Valve Springs: 1.550' Diameter - Open Pressure: 550 lbs.; Closed Pressure: 240 lbs.; Installed Height: 1.950'; Max Lift: .700'
- Spring Retainers: 1.550' 10° Titanium
- Rocker Studs: 7/16'
- Guide Plates: 5/16'
- Valve Seals: 11/32'
- Spark Plug Configuration: AngledFacts and Related Components
- Torque Heads: 70 ft-lb.
- Torque Rocker Studs: 40-45 ft-lb.
- Intake Gasket: Brodix p/n 158-MG1800, Cometic p/n 245-C3250
- Head Gasket: Fel-Pro p/n 375-1003 (350ci) / 375-1004 (400ci) or Cometic p/n 245-C5399 (350ci) / 245-C5403 (400ci)
- Exhaust Gasket: Brodix p/n 158-MG52464 (trim to fit), Cometic p/n 245-C5424 (Spread Port)
- Head Studs: ARP p/n 070-234-4727 (12-point with 3/8' center studs)
- Spark Plug Specs: 14mm Thread, .750' (3/4') Reach, Gasket Seat
- Valve Angle: 18°
- Angle Milling: .0065' per cc
- Flat Milling: .0055' per cc
- Pushrod Slots: 40/60
- Stud Girdle: 40/60 Brodix p/n 158-BR6440
- Rocker Arms: Standard 7/16 Roller Rockers, Shaft System with 40/60 Spacing
- Lifters: Standard
- Pistons: Special 18°
- Pushrods: Special Length
- Intake Face Angle: 10° Standard
- Exhaust Pattern: Stahl only
- Valve Centerline: 40/60
- Spring Pockets: 1.550' Out of the Box, May be cut to 1.625' - No larger or deeper
- Accessory Bolt Holes are Drilled
- Recommended Intake Manifold: Brodix HV 1800 (p/n 158-HV1800) / HV 1801 (p/n 158-HV1801)
Part TypeCylinder Head
BrandBRODIX
Package Height9.6
Package Width13.5
Package Length20.6
Weight72.0 PG
Part CategoryPerformance Parts
Cylinder Head MaterialAluminum
Intake Port LocationRaised
Rocker Arm Nut Thread Size (In.)7/16"-20
Exhaust Valves IncludedYes
Locks IncludedYes
Retainers IncludedYes
Lock Style10 degree
Guideplates IncludedYes
Rocker Arms IncludedNo
Oiling StyleThrough pushrod
Rocker Arm Nuts IncludedNo
Cylinder Head FinishNatural
Valve Seats MachinedYes
Intake Valve Angle18
Maximum Valve Lift0.7 in (17.78 mm)
Valve Seat MaterialDuctile iron
Heat CrossoverNo
Number Of Springs Per ValveDual
Valve Springs IncludedYes
Spark Plug StyleAngled
Valve Seat Machine Style3-angle
Damper Spring IncludedYes
Valve Guides IncludedYes
Cnc-Machined Intake RunnerYes
Intake Valves IncludedYes
QuantitySold as a pair
Valve Stem Seals IncludedYes
Intake Valve Diameter2.14 in (54.356 mm)
Accessory Bolt Holes DrilledYes
Exhaust Port LocationStandard
Valve Guide MaterialPhosphorous bronze
Outside Diameter Of Outer Spring1.55 in (39.4 mm)
Combustion Chamber Volume (Cc)68
Machined For O-RingNo
Exhaust Valve Angle18
Steam Holes DrilledNo
Rocker Arm Studs IncludedYes
Cylinder Head StyleAssembled
Part FitmentSemi Universal
Valve Cover Mounting StylePerimeter bolt
Retainer MaterialTitanium
Intake Runner Volume (Cc)253
Cnc-Machined Exhaust RunnerYes
Cnc-Machined Combustion ChamberYes
Exhaust Valve Diameter1.6 in (40.64 mm)
Vendor Part Number1188100
Package Qty1
Package TypeEA
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