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Top Street Performance

Chevy Small Block Straight Plug Flat Tappet Assembled Aluminum Cylinder Head

Chevy Small Block Straight Plug Flat Tappet Assembled Aluminum Cylinder Head

SKU: JM4120S

$605.00
$605.00
Shipping calculated at checkout.

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Top Street Performance (TSP) is committed to providing high-quality performance parts while complying with emissions regulations. This product is designed for use on vehicles that comply with federal emissions regulations. It is the customer’s responsibility to verify that this part is legal for use in their state or local jurisdiction. Check with your local emissions authority before purchasing.

Product Details

Features

  • 198cc intake runners improve Small Block Chevy airflow
  • 64cc chambers support efficient combustion and power
  • Straight plug design fits many traditional SBC setups
  • Fully assembled aluminum construction saves installation time

Description

Upgrade your Gen I Small Block Chevy engine with a fully assembled aluminum cylinder head designed to improve airflow, combustion efficiency, and horsepower potential. Featuring 198cc intake runners, 64cc combustion chambers, and 2.020" intake / 1.600" exhaust valves, these performance cylinder heads are built for street performance, muscle car, hot rod, restoration, street/strip, and bracket racing applications.

The optimized intake runner and combustion chamber design help increase airflow compared to many factory castings, supporting improved throttle response, stronger torque production, and greater horsepower potential throughout the RPM range. These Small Block Chevy aluminum heads are an excellent choice for 350 Chevy, 383 stroker, and other Gen I SBC performance builds seeking improved breathing and reduced weight.

Constructed from lightweight aluminum, these cylinder heads help reduce front-end weight while dissipating heat more efficiently than traditional iron heads. The assembled design includes valves, springs, retainers, locks, and seals, helping simplify installation for compatible flat tappet camshaft combinations.

Whether you're building a street-driven 350 Chevy, a torque-focused 383 stroker, or upgrading a classic muscle car or truck, these assembled aluminum cylinder heads provide the airflow capacity, durability, and performance-oriented design needed for serious Small Block Chevy engine builds.

 

Cylinder Head Technology
Designed with 198cc intake runners, 64cc combustion chambers, and 2.020" intake / 1.600" exhaust valves, these assembled aluminum cylinder heads are engineered to improve airflow and combustion efficiency in Gen I Small Block Chevy applications. The straight plug configuration maintains compatibility with many traditional Small Block Chevy header and spark plug arrangements while the aluminum construction helps reduce weight and improve heat dissipation.

Performance Benefits
The performance-oriented runner and chamber design help increase airflow into and out of the combustion chamber, supporting improved throttle response, stronger mid-range torque, and increased horsepower potential. Aluminum construction also helps transfer heat more efficiently than cast iron, making these cylinder heads a popular upgrade for street performance engines, muscle cars, hot rods, and street/strip combinations.

Specs

Assembled Yes
CNC Ported No
Combustion Chamber Style Heart
Combustion Chamber Volume 64 cc
Deck Height Standard
Deck Thickness Standard
Exhaust Crossover No
Exhaust Port Height 1.400 in.
Exhaust Port Location Standard
Exhaust Port Shape Square
Exhaust Port Width 1.400 in.
Exhaust Valve Diameter 1.600 in.
Exhaust Valve Material Stainless Steel
Finish Natural
Grade Type Performance
Guide Plate Material Chromoly Steel
Intake Port Height 2.100 in.
Intake Port Location Standard
Intake Port Shape Rectangle
Intake Port Width 1.180 in.
Intake Runner Volume 198 cc
Intake Valve Diameter 2.020 in.
Intake Valve Material Stainless Steel
Material Aluminum
Push Rod Diameter 0.3125 in.
Quantity Sold Individually
Spark Plug Style Straight
Valve Angle 23.0 deg.
Valve Guide Material Bronze
Valve Seat Material Steel
Valve Spring Retainer Material Steel
Valve Springs Included No
Valves Included Yes
Weight 19 lbs.

Engine Fitment

COMPATIBLE WITH
CHEVROLET SMALL BLOCK V8 GEN. I
• 4.3L / 262 in³
• 4.3L / 265 in³
• 4.4L / 267 in³
• 4.6L / 283 in³
• 4.9L / 302 in³
• 5.0L / 305 in³
• 5.0L / 307 in³
• 5.4L / 327 in³
• 5.7L / 350 in³
• 6.6L / 400 in³

COMMON VEHICLE APPLICATIONS
Chevrolet Camaro
Chevrolet Chevelle
Chevrolet Nova
Chevrolet El Camino
Chevrolet Impala
Chevrolet C10
Chevrolet C/K Series Trucks

NOTES
• Fits Gen I Small Block Chevy engines only (1955–1995)
• Straight plug design for traditional SBC applications
• Designed for flat tappet camshaft combinations
• Fully assembled with valves, springs, retainers, locks, and seals
• Verify engine component compatibility and clearances before installation
• Not compatible with LS, LT, or Big Block Chevy engines
• Cylinder head sold individually (purchase quantity of 2 required for complete engine).

Q&A

Will these cylinder heads fit a Chevy 350?
Yes, these heads are designed for Gen I Small Block Chevy 350 applications.

Can these heads be used on a 383 stroker?
Yes, they are compatible with Gen I Small Block Chevy 383 stroker combinations.

Are these cylinder heads fully assembled?
Yes, they include valves, springs, retainers, locks, and valve seals.

What size intake runners do these heads have?
They feature 198cc intake runners.

What size combustion chambers do these heads use?
These cylinder heads feature 64cc combustion chambers.

What valve sizes are included?
They include 2.020" intake valves and 1.600" exhaust valves.

What is the benefit of a straight plug design?
Straight plug heads are compatible with many traditional Small Block Chevy header and spark plug configurations.

Are these designed for flat tappet camshafts?
Yes, this version is intended for flat tappet camshaft applications.

Can aluminum cylinder heads improve performance?
Aluminum heads can improve airflow, reduce weight, and dissipate heat more efficiently than comparable iron castings.

Are these suitable for street performance builds?
Yes, they are designed for street performance, muscle car, hot rod, street/strip, and performance rebuild applications.

Do I need to verify piston-to-valve clearance?
Yes, clearance should always be checked during engine assembly.

Are these compatible with LS engines?
No, these cylinder heads are designed for Gen I Small Block Chevy engines and are not compatible with LS platforms.

Emissions Notice

This product is legal for off road use and non pollution controlled vehicles (1965 & older); however, it has not been tested or approved by the California Air Resources Board (CARB) for highway vehicles in the state of California. By purchasing this product, buyer agrees it will not be used on pollution controlled vehicles in California, or in a state with similar emissions regulations.