AFR's 227cc "Race Ready" and "Competition" LT4 heads feature 100% CNC ported intake, exhaust & chambers, A356 aluminum castings and high quality components throughout. This head features 60/40 valve spacing and requires shaft mount rocker arms for optimum valve train geometry (can be used with .050 offset intake rockers for drag race only applications).
Included Components | |
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, 2.100" x 5.000" Overall Valve Length | |
8mm Bead Lock Exhaust Valve, 1.600" x 5.030" Overall Valve Length | |
PAC Racing Spring 1.550" OD Solid Roller Dual Valve Spring, 220 lbs on seat, .710" maximum lift, Max RPM 7200-7400 | |
Manley 10° Steel Retainers 1.500" O.D x 1.120" I.D x .705" I.D | |
10° Bead Lock Valve Keepers with lashcap recess | |
ARP 7/16" Rocker Studs | |
Adjustable 5/16" Guide Plates | |
Viton Valve Seals .600" O.D x .495" I.D | |
Hardened Valve Spring I.D Locator 1.550" O.D x .705" I.D | |
Ductile Iron Intake Valve Seats 2.200" O.D x 1.750" I.D x.375" Deep | |
Ductile Iron Exhaust Valve Seats 1.696" O.D x 1.325" I.D x .305" Deep | |
8mm Bronze Valve Guides .502" O.D x 2.100" O.A.L |
227cc Race Ready Head Flow Chart | ||||||||
.200 | .300 | .400 | .500 | .550 | .600 | .650 | .700 | |
Int | 148 | 210 | 261 | 296 | 304 | 312 | 315 | 318 |
Exh | 114 | 155 | 204 | 220 | 225 | 229 | 233 | 237 |
227cc Competition Head Flow Chart | |||||||||
.200 | .300 | .400 | .500 | .550 | .600 | .650 | .700 | .750 | |
Int | 152 | 212 | 265 | 300 | 312 | 319 | 324 | 327 | 329 |
Exh | 120 | 167 | 214 | 230 | 234 | 238 | 241 | 243 | 245 |
Test conducted at 28" of water (pressure) on Superflow 1020
Bore Size: 4.155", 3/4" radius plate exhaust, 1 7/8" curved pipe
Specifications & Features: | |
Material |
A356 Aluminum
|
Intake Port Volume |
227cc
|
Intake Port Dimension |
2.200" H x 1.290" W 5/16 Radius
|
Intake Port Location |
Stock
|
Exhaust Port Volume |
80cc
|
Exhaust Port Dimension |
1.430" H x 1.540" W
|
Exhaust Port Location |
.250" Raised
|
Combustion Chamber Size |
65cc or 75cc
|
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
|
Warning: Do not machine spring pad any deeper. | |
Deck Thickness |
.750"
|
Minimum Bore Diameter |
4.000"
|
Flat Mill |
.006" per cc 60cc Maximum
|
Angle Mill |
.009" per cc 55cc Maximum
|
Note: Angle mills might require .120" Thick intake gasket. | |
Minimum Cross Sectional Area |
2.340 sq. in.
|
Spark Plug Dimensions |
14mm x .750" w/Gasket Seat
|
Carb EO# |
Non Emissions Compliant
|
Recommended Components: | |
1.5 T&D Shaft Mount w/ .450" off-set | |
1.6 T&D Shaft Mount w/ .450" off-set | |
1.6 Stud Mount Rocker Arms, Hardland Sharp .050 offset | |
1.5 Stud Mount Rocker Arms, Hardland Sharp .050 offset | |
Intake Gasket | |
Important: Do not use your AFR gasket as a template to port match your intake manifold as one AFR gasket is used for many AFR runner volumes. | |
Exhaust Port Gasket, Fel-Pro #1405 | |
Head Gasket, LT1 Fel-Pro #1074 | |
SB Chevy Head Bolt Kit, ARP #134-3701 | |
SB Chevy Head Stud Kit, 12 Point Nuts, ARP #234-4301 | |
Head Bolt Washers, Manley | |
Stud Girdle AFR Offset | |
Suggested Manifold |
GM LT4 or Edelbrock LT4
|
Spark Plug Starting Range |
Autolite 3922
|
Item# | Description | Qty. | MSRP | Your Price | ||
---|---|---|---|---|---|---|
1076 |
227cc SBC LT4 Race Cylinder Head |
$2,459.46 |
ADD TO CART
|
|||
1126 |
227cc SBC LT4 Race Cylinder Head |
$3,170.43 |
ADD TO CART
|
Footnotes
AFR Small Block Chevy
General Recommendations for AFR Cylinder Heads:
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