A cost effective choice compared to re-worked factory heads, our 205cc package features fully CNC ported intake and exhaust runners, and combustion chambers. Recommended for street, street/strip and towing applications with displacements up to 383 cubic inches, operating at or below 6300 RPM. A minimum 3.900" bore size is required to clear the supplied 2.020" valve. These heads are legal for use on 2005 and older emissions controlled vehicles, under CARB EO #D-250-4.
*LSX bead locks and aftermarket bead locks are not interchangeable. GM made their bead lock radius and depth different. AFR locks are the same as GM LSX.
| 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, 2.020” x 4.900" Overall Valve Length | |
| 8mm Bead Lock Exhaust Valve, 1.600” x 4.900" Overall Valve Length | |
|
PAC Racing Spring 1.290" OD Hydraulic Roller Dual Valve Spring, 140 lbs on seat, .600" maximum lift, Max RPM 6300-6500, less than 235* duration, upgraded spring #8019 recommended for higher RPM & larger cams |
|
| 7° Titanium Retainers 1.245" O.D x .885" I.D x .655" I.D | |
| 7° Bead Lock Valve Keepers | |
| Viton Valve Seals .600" O.D x .495" I.D | |
| Hardened Valve Spring O.D Locator 1.380" O.D x .570" I.D | |
| 205cc Competition Flow Chart | ||||||
| .200 | .300 | .400 | .500 | .550 | .600 | |
| Int | 147 | 214 | 249 | 284 | 296 | 301 |
| Exh | 111 | 150 | 209 | 225 | 230 | 233 |
Test conducted at 28" of water (pressure) on Superflow 1020
Bore Size: 3.900", intake 3/4" radius plate exhaust, 1 3/4" curved pipe
| Specifications & Features: | |
| Material |
A356 Aluminum
|
| Intake Port Volume |
205cc
|
| Intake Port Dimension |
3.275"H x 1.120"W x5/16 top 3/8 bottom
|
| Intake Port Location |
Stock
|
| Exhaust Port Volume |
84cc
|
| Exhaust Port Dimension |
1.415" H x 1.710" W
|
| Exhaust Port Location |
Stock
|
| Combustion Chamber Size |
66cc
|
| Valve Cover Bolt Pattern |
Center Bolt
|
| Valve Angle |
15°
|
| Valve Spring Pocket Diameter |
1.510" O.D
|
| Max Valve Spring Pocket Machining |
1.525" O.D
|
| Deck Thickness |
.750"
|
| Minimum Bore Diameter |
3.900"
|
| Flat Mill |
.006" per cc 58cc Maximum
|
| Minimum Cross Sectional Area |
2.185 sq. in.
|
| Spark Plug Dimensions |
14mm x .750" w/Tapered Seat
|
| CARB E.O. |
#D-250-4
|
| Recommended Components: | |
| Intake Port Gasket |
GM or FAST
|
| Exhaust Port Gasket |
GM#12558573
|
| Head Gasket |
Cometic 3.930 .040” or AFR #6846
|
| Head Bolts (97-03) |
ARP 134-3609 or AFR #6330
|
| Head Studs (97-03) |
ARP 234-4110 or AFR #6331
|
| Head Bolts (04+) |
ARP 134-3610 or AFR #6334
|
| Head Studs (04+) |
ARP 234-4317 or AFR #6335
|
| Head Bolt Washers, Manley | |
| Suggested Manifold |
FAST 90mm, 92mm, or 102mm
|
| Spark Plug Starting Range |
NGK TR55
|
| Sku | Description | Qty |
|---|---|---|
| 8017-16 | (Set of 16) AFR 8017 - 1.290" OD Hydraulic Roller | 1 |
| 9007-16 | (Set of 16) AFR 9007 - 7 Degree Valve Lock 8mm | 1 |
| 6612-16 | (Set of 16) AFR 6612-16 - SBC, SBF, LS1 Valve Seal | 1 |
| 8042-16 | (Set of 16) AFR 8042 - OD Spring Cup 1.380 OD x 1.300 ID x .570 ID | 1 |
| 7207-8 | (Set of 8) AFR 7207 - LS1 8mm Solid Stem Intake Valve 2.020 x 4.900 OAL | 1 |
| 7228-8 | (Set of 8) AFR 7228 - LS1 Solid Stem 8mm Exhaust Valve 1.600" x 4.900" | 1 |
| 8512-16 | (Set of 16) AFR 8512 - 7 Degree Titanium Retainer 1.250 OD x .885 ID x .655 ID | 1 |
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