Overview
Brand:
PROMAXX Performance
Manufacturer’s Part Number:
2121
Part Type:
Cylinder Heads
Product Line:
PROMAXX Performance Freedom Series Small Block Chevy Cylinder Heads
Summit Racing Part Number:
PMX-2121
Combustion Chamber Volume (cc):
64
Intake Runner Volume (cc):
225cc
Exhaust Runner Volume (cc):
62cc
Cylinder Head Style:
Assembled
Cylinder Head Material:
Aluminum
Intake Port Shape:
Rectangular
Intake Valve Diameter (in.):
2.080 in.
CNC-Machined Combustion Chamber:
No
CNC-Machined Intake Runner:
No
CNC-Machined Exhaust Runner:
No
Intake Port Location:
Standard
Exhaust Port Shape:
Square
Exhaust Port Location:
Standard
Spark Plug Style:
Straight
Intake Valves Included:
Yes
Exhaust Valves Included:
Yes
Exhaust Valve Diameter (in.):
1.600 in.
Valve Springs Included:
Yes
Maximum Valve Lift (in.):
0.575 in.
Camshaft Style:
Hydraulic flat tappet
Damper Spring Included:
No
Retainers Included:
Yes
Retainer Material:
Steel
Locks Included:
Yes
Valve Stem Seals Included:
Yes
Rocker Arm Studs Included:
Yes
Rocker Arm Nut Thread Size:
3/8 in.-24
Rocker Arms Included:
No
Rocker Arm Nuts Included:
No
Guideplates Included:
Yes
Guideplate Pushrod Size:
5/16 in.
Valve Cover Mounting Style:
Perimeter bolt
Accessory Bolt Holes Drilled:
Yes
Valve Guides Included:
Yes
Valve Guide Material:
Manganese bronze
Valve Seats Machined:
Yes
Valve Seat Machine Style:
5-angle
Valve Seat Material:
Steel
Cylinder Head Color:
Natural
Steam Holes Drilled:
No
Machined for O-Ring:
No
Heat Crossover:
No
Quantity:
Sold as a pair.
Notes:
The larger intake ports on these heads will not accommodate stock or low rise style intakes. Please see the Recommend Parts tab for compatible intake manifolds. Blended bowls with 21-4N stainless steel valves; recommended for 383 c.i.d. and larger engines with hydraulic flat tappet camshafts. Steam holes can be added for 400 c.i.d. engines.
PROMAXX Performance Freedom Series Small Block Chevy Cylinder Heads
PROMAXX Performance Freedom Series small block Chevy cylinder heads offer exceptional quality at an unbelievable price. Manufactured from high-quality aluminum, they are assembled with the finest components. Freedom Series cylinder heads feature one-piece stainless steel intake and exhaust valves, enhanced intake runners, and performance valve springs with steel retainers. They’re available in straight or angle plug designs. Horsepower costs money. With Freedom Series small block Chevy cylinder heads, PROMAXX Performance offers you the opportunity to bolt on the power that you’ve been looking for, at the price you want.