Engines and Components› Cylinder Heads and Components

Manley Performance

Manley Chevrolet Small Block Intake Valve Kit - 2.125in Head Dia. 5.110in O/A Length, 0.3110in Stem

$490.07

SKU: M004 12320-8

In Stock
In Stock
Ships by Jun 20
Free Shipping
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Advanced — 4+ hours

Description

The Manley Performance 12320-8 is a set of eight Race Master intake valves. These valves are constructed from NK-842 Stainless Steel for durability, with chrome stems and hard tips for longevity. They feature swirl-polished under-head areas and machined combustion faces to optimize airflow.

Fitment

Fitment Guaranteed

Don’t gamble
on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandManley Performance
Part NumberM004 12320-8

Videos

Manley Performance Factory Tour - Pistons, Connecting Rods, Valvetrain Manufacturing | RS Garage

Manley Performance Factory Tour - Pistons, Connecting Rods, Valvetrain Manufacturing | RS Garage
Valve Springs: How to Choose, Set Up & Install Them Right (For Your BUILD!)

Valve Springs: How to Choose, Set Up & Install Them Right (For Your BUILD!)
How to Install Valves & Springs on a LS 799 GM Cylinder Head with Michigan Motorsports

How to Install Valves & Springs on a LS 799 GM Cylinder Head with Michigan Motorsports
Understand THIS Before Buying Valve Springs | Valvetrain Terminology 101 - Jays Tech Tip

Understand THIS Before Buying Valve Springs | Valvetrain Terminology 101 - Jays Tech Tip
One Reason To Put Larger Intake Valves In A Head

One Reason To Put Larger Intake Valves In A Head
How To Lap Valves, Spring Height Micrometer, and Reface Valve Stems [EXPLAINED]

How To Lap Valves, Spring Height Micrometer, and Reface Valve Stems [EXPLAINED]
Why You NEVER ATTEMPT To Use RTV Gasket Maker Without Doing This First!!

Why You NEVER ATTEMPT To Use RTV Gasket Maker Without Doing This First!!

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

View Full Return Policy