ProMaxx Performance 2121 - Patriot Performance SB-Chevy 225CC Freedom Series Heads
ProMaxx Performance#723-2121225cc Aluminum Cylinder Heads
Patriot Performance expanded the Freedom Series heads to include their newest 225cc runner. To achieve the best flowing cylinder heads Patriot performs their 2.08''/1.60'' 5-angle valve job, hand blend the valve bowl area, and mill to exact tolerances. To this they add only the highest quality EV8 2.08''/1.60'' stainless valves, .575'' lift (hyd. flat tappet) springs, steel retainers, 3/8'' studs, bronze guides, and guide plates. These heads are a great addition to engine builds that are 383ci and larger. Note: Due to high intake runner position, most intakes will require 1/8" thick Fel Pro 1266 gasket.
Combustion Chamber: 64cc
Intake Runner: 225cc
Exhaust Runner: 62cc
Intake Valve: 2.02'' or 2.08''
Exhaust Valve: 1.60''
Max. Valve Spring Lift: 0.575''
Spring Pressure Closed: 115 lbs. @ 1.800''
Spring Pressure Open: 310 lbs. @ 1.225''
Retainer Material: Steel
Valve Seal Material: Viton
Valve Guide Material: Manganese Bronze
Valve Job: 5-angle
Uses .750 reach gasket seat spark plugs (Autolite 410-AR3924 Suggested)
Note: Due to high intake runner position, most intakes will require 1/8" thick Fel Pro 1266 gasket.