Proflow Cylinder Heads, AirMax 290, Aluminium, BB Chevrolet, Bare

Proflow does not sacrifice quality for a low price--you get both with our aluminium cylinder heads. The lightweight heads are cast from A-356 aluminium alloy with a large choice of engine, for SB & BB Chevrolet, LS Chev Holden Ford SB 289-351W, 302, 351 Cleveland 2V & 3V & BB FE, and Chrysler SB & BB. They have phosphorous bronze valve guides, and ductile iron valve seats for use with unleaded gas. They're also end-milled and drilled for accessories. The fully assembled heads have stainless steel valves, high performance valve springs, 7 degree valve locks, rocker arm studs, and guideplates. Perfect for your Mild or High performance Hot Rod.

Specifications & Features:
Material A356.2 Aluminum
Intake Port Volume 290cc
Intake seat size 2.25 OR 2.30
Exhaust seat size 1.88
Intake Port Dimension 2.030"H x 1.830"W x1/2 Radius
Intake Port Location Stock
Exhaust Port Volume 135cc
Exhaust Port Dimension 1.770"H x 2.010" W
Exhaust Port Location .375" Raised
Combustion Chamber Size 112cc
Valve Cover Bolt Pattern Perimeter Bolt
Valve Angle 24/4 Int, 15/4 Exh
Valve Spring Pocket Diameter 1.725" O.D
Max Valve Spring Pocket Machining 1.750" O.D
Deck Thickness .750"
Minimum Bore Diameter 4.250"
Flat Mill .006" per cc/ Maximum 102cc
Angle Mill .009" per cc/ Maximum 97cc
Note:Angle mills might require a .120" Thick intake gasket.
Minimum Cross Sectional Area 2.895 sq. in.
Spark Plug Dimensions 14mm x .750" w/Gasket Seat
Intake Valve Seat Machine Style: 5-angle
11/32" Intake Valve, 2.250" x 5.500" O.A.L
11/32" Nail Head Exhaust Valve, 1.880" x 5.450" Overall Valve Length
Racing Springs#1940 1.550" O.D. Hydraulic Roller Dual Valve Spring, 175 lbs. on seat, .725" maximum lift, 473lbs @ .600 lift, Max RPM 6500-6700
Racing Spring 1.550 O.D. Solid Roller Valve Spring, 220lbs on seat, .710" Maximum Lift, Max RPM 7200-7400 (upgrades available)
Manley 10 Steel Retainers 1.500" O.D x 1.120"I.D x .705" I.D
10 11/32" Valve Locks with lashcap recess
ARP 7/16" Rocker Exhaust Studs
ARP 7/16" Rocker Intake Studs
3/8" Guide Plates
11/32" Viton Valve Seals
Hardened Valve Spring I.D Locator 1.550" O.D x .780" I.D
Intake Valve Seats 2.450" O.D x 1.950" I.D x .375" Deep
Exhaust Valve Seats 2.000" O.D x 1.580" I.D x .375" Deep
11/32" Intake Bronze Valve Guides .502" O.D x 2.10" O.A.L
11/32" Exhaust Bronze Valve Guides .502" O.D x 2.25" O.A.L
Recommended Components:
Intake Port Gasket
Important: Do not port match your intake manifold to Fel-Pro gasket as it does not precisely fit the heads.
Exhaust Port Gasket
Head Gasket, Fel-Pro #1047 (Mark V and VI)
Head Gasket,, Fel-Pro #1017-1 (Mark IV)
Head Bolts, ARP 135-3703 (Mark IV)
Head Bolts, ARP 135-3707 (Mark V)
Head Studs, ARP 235-4713
Head Bolt Washers, Manley
Stud Girdle
7/16 Stud Mount Rocker Arms - 1.7 Ratio (For Optimized Geometry)
1.7 Shaft Mount Rocker Arms Aftermarket
Suggested Manifold Victor Jr
Suggested Manifold RPM Performer
Spark Plug Starting Range Autolite 3924