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AFR 245cc Competition Eliminator SBC Cylinder Heads, 70cc Chambers

AFR 1137
AFR's 245cc "Competition" heads feature 100% CNC ported intake, exhaust & chambers, A356 aluminum castings and high quality components throughout. NPP stands for "no pushrod pinch", and this is AFR's largest 60/40 valve spacing head. These heads require shaft mount rocker arms for all applications and have extra machining for 3/8" pushrod clearance. Component upgrade and machining options are available to customize AFR Heads to your specific build.
Shipping: FREE continental USA ground shipping on ALL AFR Cylinder Heads
Was: $3,099.00
Sale: $2,399.99
Save: 23%
Save: $699.01

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The Best 23° AFR Head Ever Produced!
AFR is proud to introduce the new 245 NPP (no pushrod pinch); best suited for max effort applications, but larger displacement 427+ pump gas engines could consider this head as well. This exciting product represents the best flowing 23° SBC head to date and while flow numbers may reflect a very good 18° head of the past, this head is still a conventional direct bolt on non-raised runner intake port configuration. It will drop on your 23° shortblock as easily as the 227cc or 235cc AFR SBC product and in fact shares identical valve centerlines and rocker stud locations to both of those heads. However, unlike the 227 and 235 cc heads, this product will not accept stud mount style rockers and a shaft mount rocker system with the proper intake offset must be used. This is primarily due to the enlarged and widened pushrod pinch removing that checkpoint in the entrance of the intake allowing AFR to design a port with a more direct shot at the back of the valve that also has a more consistent cross sectional area and velocity profile. In addition, this head comes standard with a 3/4 inch deck, 2.125 intake and 1.600 exhaust. If you are unsure if this is the right AFR head for you, we encourage you to contact us directly to discuss your combination. Dual valve cover bolt pattern is standard.
The exhaust ports are raised .250" over a standard GM L-98 cylinder head.

2.125 valves will require aftermarket pistons notched for valve clearance.

Basic Package Components Part #
100% CNC Ported Combustion Chambers
100% CNC Ported Exhaust Ports
100% CNC Ported Intake Ports
Competition 5-angle Valve Job

8mm Bead Lock Intake Valve, 2.125" x 5.00" long AFR #7253
8mm Bead Lock Exhaust Valve, 1.600" x 5.030" Overall Valve Length AFR #7254
PAC Racing Springs 1.550" OD Solid Roller Dual Valve Spring Pac #1225, 250 lbs on seat, .800" maximum lift, Max RPM 8000-8200 AFR #8001
Manley 10° Steel Retainers 1.500" O.D x 1.120" I.D x .705" I.D AFR #8511
10° Bead Lock Valve Keepers with lashcap recess AFR #9009
Viton Valve Seals .600" O.D x .495" I.D AFR #6612
Hardened Valve Spring I.D Locator 1.550" O.D x .780" I.D AFR #8048
Ductile Iron Intake Valve Seats 2.200" O.D x 1.750" I.D x .375" Deep AFR #9060
Ductile Iron Exhaust Valve Seats 1.696" O.D x 1.325" I.D x .305" Deep AFR #9070
Bronze Valve Guides AFR #9051

Specifications, Features, and Optional Supporting Components
Head Material

A356 Aluminum

Intake Port Volume 245cc
Intake Port Dimension 2.200" H x 1.300" W 7/16 Radius
Intake Port Location
Exhaust Port Volume 80cc
Exhaust Port Dimension 1.465" H x 1.570" W
Exhaust Port Location .250" Raised
Combustion Chamber Size 70cc or 80cc
Valve Cover Bolt Pattern
Perimeter Bolt
Valve Angle 23°
Valve Spring Pocket Diameter 1.580" O.D
Max Valve Spring Pocket Machining

1.680" O.D

Deck Thickness
Minimum Bore Diameter 4.000"
Flat Mill .006" per cc 60cc Maximum
Angle Mill .009" per cc 55cc Maximum
Minimum Cross Sectional Area
2.730 sq. in.
Note:Angle mills might require a .120" Thick intake gasket.
Spark Plug Dimensions 14mm x .750" w/Gasket Seat
Carb EO#
Non Emissions Compliant
Shaft Mount Rocker Arms, T&D .450" offset (requires .180 offset lifters)
Shaft Mount Rocker Arms T&D .550" offset (with standard lifters)
Intake Gasket 1.280x2.090 w/ 3/8" radius, Fel-Pro #1206 AFR #6820
Exhaust Port Gasket, Fel-Pro #1405 AFR #6835
Head Gasket, 350cid Fel-Pro #1004 AFR #6801
Head Gasket, 400cid Fel-Pro #1014 AFR #6802
SB Chevy Head Bolt Kit, ARP #134-3701 AFR #6310
SB Chevy Head Stud Kit, 12 Point Nuts, ARP #234-4301 AFR #6305
Head Bolt Washers, Manley AFR #6320
Suggested Manifold AFR Titan TXR #4801
Suggested Manifold AFR  Titan TXS #4802
Spark Plug Starting Range Autolite 3922
Important: Do not port match you intake manifold to any Fel-Pro gasket as it does not precisely match AFR heads.
Note: Milling head deck will affect flow numbers.


Shipping Information

  • Item Requires Shipping
  • 65.0 lbs.
  • W12.0000” x H12.0000” x L24.0000”
  • This item ships in its own box.
  • FREE continental USA ground shipping on ALL AFR Cylinder Heads

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