GM Performance Cylinder Head, Assembled, 118cc Combustion Chambers, 325cc Intake Ports, 110cc
Part Number:GMP-12562920
GM Performance Cylinder Head, Assembled, 118cc Combustion Chambers, 325cc Intake Ports, 110cc Exhaust Ports, GM, 454/502, Each (PART #GMP-12562920)
These GM Performance High Output crate engine cast iron cylinder heads are designed for use with the Gen V and Gen VI design, 454 big block V8 crate engines. They feature a 118cc open combustion chamber with 2.18 in. intake valves and 1.88 in. exhaust valves with rectangular intake ports. The cylinder heads use 3/8 in. rocker arm holes for standard stud-mount type rocker arms.
SPECIFICATIONS |
|
| Brand | GM Performance |
| Manufacturer's Part Number | 12562920 |
| Part Type | Cylinder Heads |
| Product Line | GM Performance High Output Crate Engine Cast Iron Cylinder Heads |
| Combustion Chamber Volume (cc) | 118 |
| Intake Runner Volume (cc) | 325cc |
| Exhaust Runner Volume (cc) | 110cc |
| Cylinder Head Style | Assembled |
| Cylinder Head Material | Cast iron |
| Intake Port Shape | Rectangular |
| Intake Valve Diameter (in.) | 2.180 in. |
| CNC-Machined Combustion Chamber | No |
| CNC-Machined Intake Runner | No |
| CNC-Machined Exhaust Runner | No |
| Combustion Chamber Style | Open chamber |
| Intake Port Location | Standard |
| Exhaust Port Shape | Round |
| Exhaust Port Location | Standard |
| Intake Valves Included | Yes |
| Exhaust Valves Included | Yes |
| Exhaust Valve Diameter (in.) | 1.880 in. |
| Valve Springs Included | Yes |
| Maximum Valve Lift (in.) | 0.600 in. |
| Outside Diameter of Outer Spring (in.) | 1.487 in. |
| Damper Spring Included | No |
| Number of Springs Per Valve | Single |
| Retainers Included | Yes |
| Retainer Material | Steel |
| Locks Included | Yes |
| Lock Style | 10 degree |
| Valve Stem Seals Included | Yes |
| Valve Stem Seal Style | Positive stop |
| Rocker Arm Studs Included | No |
| Rocker Arm Nut Thread Size | 3/8 in.-24 |
| Rocker Arms Included | No |
| Rocker Arm Nuts Included | No |
| Guideplates Included | No |
| Valve Cover Mounting Style | Center and perimeter bolt |
| Accessory Bolt Holes Drilled | Yes |
| Valve Guides Included | Yes |
| Valve Guide Material | Bronze |
| Valve Seats Machined | Yes |
| Valve Seat Material | Steel |
| Cylinder Head Color | Natural |
| Steam Holes Drilled | No |
| Oiling Style | Through pushrod |
| Machined for O-Ring | No |
| Heat Crossover | No |
| Remanufactured | No |
| Quantity | Sold individually. |
| Notes | Will not fit GM Mark IV cylinder blocks. Will not work on L29 engine. |
