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["As Cast","cylinder heads","Factory Mast","Hydraulic","LS","ls3","medium bore","W\/ Stainless Valves","W\/ Titanium Valves","W\/ Valves"]
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Cathedral/LS3 Small Bore | Factory Mast | As Cast | Cylinder Head - Pair w/ Valves
Description
Description
COMING SOON TO PRE-ORDER
Introducing one of the first 5.3 Liter LS3 cylinder heads designed for use with the LS3 intake without adapters. Optimized for 3.780 bore diameter.
***Download the Tech Sheet Here***
We launched our Factory Mast product line to deliver an economical product line for our customers.
You have come to love the "Black Label" Cylinder heads, but now you can get the same quality at a lower price without SACRIFICING performance.
Manufactured using permanent mold technology, this casting is simply an amazing surface finish and quality.
Mast refuses to compromise on materials and methods that may jeopardize longevity, performance, and quality. When buying Mast Cylinder heads, you are getting the highest level of quality and performance on the market.
Full Send, no compromises, no shortcuts, ever.
Dimensional Specs
Bore Size: 3.78 0 (+)
Weight: 28.5 lbs.
Intake Valve Size: 2.040"
Exhaust Valve Size: 1.570"
Valve Stem Diameter: 5/16"
Valve Length: 5.450"
Valve Angle: 11 °
Valve Spring Pocket Diameter: 1.580"
Valve Spring Install Height: 1.800"
Head Stud Size: .4375"
Valve Guide OD: 0.565"
Valve Job Type: 5 Angle
Air Flow & Performance Criteria
Intake Max. Flow: 312 CFM @ 6.000"
Exhaust Max. Flow: 223 CFM @ 8.000"
Intake Average Flow: 229 CFM
Exhaust Average Flow: 168 CFM
Intake Seat Material: High Chrome Alloy Steel
Intake Port Volume: 256cc
Exhaust Port Volume: 99 cc
Standard Chamber Volume: 64cc
Port Type: As Cast
Materials
Cylinder Head Material: A357-T6 Aluminum
Intake Valve Seat Material: High Chrome Alloy Steel
Exhaust Valve Seat Material: High Chrome Alloy Steel
Deck Thickness: .750"
Rocker Stand Type: Mast Billet
Guide Material: Bronze
General
Rocker Stand Type: Mast Billet
Rocker Stands Included: Yes
Rocker Stand Dowels Included: Yes
Uses Stock Rocker Bolts: No
Rocker Bolts Included: No
Rocker Arm Type: OE LS3 1.7 or Aftermarket
Head Bolt QTY: 6 Bolt Style
Valve Cover Rail Height: + ½ inch
Can use OE Valve Cover: Yes
Custom Options Available
Head Assembly
Custom Chamber Size
Chamber Softening
1/2" Head Studs
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