They’re great out of the box in “as cast” form. With 235cc intake runners they’ll provide ample flow to keep up with the camshaft/intake combinations of most larger displacement small block Chevy engines. For those who desire optimum performance, World Products offers these heads CNC-ported. With 250cc intake runners and enlarged, 90cc exhaust ports. The CNC ported heads also boast a larger 2.100” Manley stainless steel intake valves, so you can readily see the kind of power these designs will deliver. These are the very same heads World uses on their Small Block Chevy Engines.
They’re available bare, or in three different assemblies that are designed to match your camshaft’s valve spring requirements. A multi-angle valve job and Manley stainless steel valves make the assemblies an excellent value and a real time-saver for engine builders.
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TECHNICAL SPECS
Casting ID Number: WOR-077A
Material: 355-T6 alloy high density aluminum
Valve Seats: Intake (hardened), exhaust (hardened)
Valve Guides: Manganese bronze
Spring Seats: Machined for 1.560"
Valves: Manley stainless steel valves in assemblies
Valve Diameter: 2.080" intake, 1.600" exhaust (11/32" stem) as cast,
Valve Diameter CNC ported: 2.100" intake, 1.600" exhaust (11/32" stem)
Guide Plates: Stock (Special guide plates required for 235cc head, part #830456)
Rocker Arm Studs: Screw-in style
Rocker Arms: 1.5 offset ratio (use of 1.6 ratio may require elongation of pushrod holes)
Intake Runner: 235cc, standard port location
Exhaust Ports: 70cc standard location
Combustion Chamber: 64cc, angled plug orientation
Spark Plug: 14mm .750" reach gasket style. Accel 416 or equivalent
Valve Job: Multi-angle intake and radiused exhaust
Valve Cover Rail: Raised w/ perimeter and center bolt pattern
Valve Angle: Stock 23°
Accessory Bolt Holes: Stock
HEAD FLOW @ .800 LIFT
286 intake, 204 exhaust (Super Flow 1050)
304 intake, 219 exhaust (Super Flow 600)
CNC Ported Head @ .800 Lift
306 intake, 220 exhaust (Super Flow 1050)
329 intake, 238 exhaust (Super Flow 600)
All heads flowed with a standard .750" intake plate, without exhaust tube, and 28" of water.
CLICK HERE FOR COMPLETE HEAD FLOW DATA ON ALL OUR HEADS
MOTOWN 23 DEGREE ALUMINUM
HEAD ASSEMBLY BUYING GUIDE
Use this guide to match your Cam Spring Specs to our Assembled Heads & choose which assembly you need from the choices below. Please Note: Bare Heads contain no Valves. |
-1 Assembled Heads: Hydraulic Flat Tappet Cam
1.250": 100 lbs. @ 1.810", 300 lbs. @ 1.250", coil bind @ 1.200"
MAX LIFT @ .570"
-2 Assembled Heads: Mech. Flat Tappet or
Hydraulic Roller Cam
1.437": 125 lbs. @ 1.850", 340 lbs. @ 1.210", coil bind @ 1.160
MAX LIFT @ .600"
-3 Assembled Heads: Solid Roller Cam
1.550": 200 lbs. @ 1.900", 480 lbs. @ 1.200", coil bind @ 1.150", max lift
MAX LIFT
@ .700" |
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