Part#: ALL-20314PC
Manufacturer: Chevrolet
Year Range: 03-09
Engine Size: 5.3L - V8
Description: CNC Ported LM4/LM7 706/862 PAIR
Intake - 243CC
Exhaust - 95CC
Combustion chamber - 62CC
ALL Flow data is located in the pictures.
These are CNC-ported heads. They come with the following
New QualCast 21-4N Stainless Steel Swirl Polished Valves
Intake is 2.00 and Exhaust is 1.57
New Qualcast DUAL Springs for up to .650 lift.
New retainers, spring seats and valve seals.
You may look at other LS heads as well for different applications.
For a little less compression try the 243/799 heads: LS1/LS6 CNC Ported 243 Heads & 799 Heads for sale – Allied Motor Parts
For your forced air application try the 317 heads: LQ4/LQ9 CNC Ported 317 Heads .650 Springs 2.02/1.59 Valves PAIR – Allied Motor Parts
Elevate your Chevrolet engine's performance with our meticulously crafted CNC Ported LM4/LM7 706/862 Cylinder Heads. Designed for the 5.3L V8 engine (03-09), these heads surpass OEM standards, offering unparalleled power and efficiency.
Featuring .650 springs and 2.00/1.57 valves, our ALL-20314PC heads are the ultimate upgrade for enthusiasts aiming for superior performance. Whether you're searching for ported 706 heads, 706 ported heads, or high-quality ported 5.3 heads, we have the perfect solution for you.
Explore our range of 862 heads for sale, expertly ported to enhance your engine's capabilities. Our dedication to 706 head porting and 862 head porting ensures that you receive heads that maximize your engine's potential.
At Allied Motor Parts, we take pride in our products and our customers' satisfaction. Our commitment to quality and performance backs our 706 ported heads and 862 heads for sale. We stand behind our products, ensuring you get the best value for your investment.
Trust Chevrolet's legendary quality and our specialized porting expertise to transform your LM4 or LM7 engine. Don't wait—experience the difference with our premium CNC Ported LM4/LM7 706/862 Cylinder Heads today!
Ready to make the leap? Contact Allied Motor Parts today for more Cylinder Heads and Chevy Cylinder Heads options and take the first step towards unlocking your Chevrolet's full potential with our premium ported 706 heads, 706 ported heads, and ported 5.3 heads. Experience the power, efficiency, and reliability that our expertly ported heads provide. Your engine deserves the best—give it the upgrade it needs with Allied Motor Parts.
If you're looking for help or have any questions, our expert support team is available through our contact form, by phone at 866-766-9955, or via email at sales@alliedmotorparts.com. We're dedicated to assisting you every step of the way. For detailed information on cylinder heads, visit our blog section.
Learn more about Chevrolet Cylinder Heads.
This Cylinder Head has a core charge of $200.00 included in the cost. This charge is FULLY REFUNDED upon return. We will include a prepaid label for the return freight.
The cylinder head included in this listing will fit the vehicles listed below. It is also important to review / confirm the fitment notes above to assure the vehicle specifics of the head are correct for your application. If you have any question that this may not be the correct head for your vehicle or need help in locating the correct head, please contact us via phone or email prior to making a purchase.
| MAKE | MODEL | YEAR | ENGINE |
|---|---|---|---|
| Chevrolet | Camaro | 1997-2002 | 5.7L 350Cu. In. V8 GAS OHV |
| Chevrolet | Corvette | 1997-2004 | 5.7L 350Cu. In. V8 GAS OHV |
| Pontiac | Firebird | 1997-2002 | 5.7L 350Cu. In. V8 GAS OHV |
Not sure this is your casting? Call 866-766-9955 with your casting number and your vehicle's year, make and engine, and we'll confirm it before you buy.
Cylinder Head Rebuilding Process
1. Initial Inspection: As a unit comes to our shop, we give it an initial inspection to determine whether there is any reason the head should not proceed to rebuilding. This quickly catches problems such as cracks, casting damage and other conditions that would halt the process for that casting.
2. Teardown: The cylinder head is fully disassembled, which reveals other areas of potential damage to the casting. The parts and the head are separated and go through different cleaning processes.
3. Cleaning: Cast iron heads are cleaned in a thermal cleaning system — baked at 600° to reduce grease and oil to ash, then put through a steel-shot machine for a brilliant finish. Aluminum heads are baked at a lower temperature or put through a high-pressure wash, then glass-beaded.
4. Head Inspection: After cleaning, heads are pressure tested or Magnafluxed to find any cracks. All bolt holes, valve guides, valve seats and other areas are inspected for broken bolts, broken taps, cracked guides and other impairments. Straightness and cam bore wear are also checked.
5. Machining: All heads have guides installed to meet OE conditions and are resurfaced to far exceed factory specifications for surface finish. A three-angle valve job achieves valve seat runout under .001". Valves are ground for a perfect seal between valve and seat.
6. Assembly: New OE-style valve guide seals are installed. Springs are tested for proper seat pressure. Valve seat sealing is vacuum-checked for an airtight fit. Lifters are bled and rebuilt for zero lash after startup. Cams are polished and clearances are checked twice to meet OE oil clearances.
7. Final Inspection: Every head is visually inspected — surface finish, lash, bolt holes and all other areas — to ensure a quality cylinder head.
Questions about our cylinder head services? Call 1-866-766-9955.
Warranty — 12 months from purchase
Match the head before installation. We will not warranty an incorrectly installed head. Call us immediately with any questions or concerns about your purchase.
First 3 months:
- Repair or replacement of the cylinder head.
- Gasket set supplied for reinstallation.
- Labor calculated from book time at $25.00 per hour, up to a maximum of 10 hours.
- Replacement of fluids and filters.
Remaining 9 months:
- Repair or replacement of the cylinder head.
- Gasket set supplied for reinstallation.
- Replacement of fluids and filters.
- No labor is covered.
Warranty is void if:
- The head was improperly installed.
- The head was overheated (heat tab melted or missing).
- The head received insufficient oiling.
- The cooling system operated improperly.
Warranty returns must be sent to Allied Motor Parts uncleaned and fully assembled — any disassembly voids the warranty — and must be accompanied by proof of purchase. There is no warranty on threaded bolt holes after installation.
This warranty is in lieu of any other warranty, expressed or implied, including any implied warranty of merchantability or fitness for a particular purpose.
Here’s why our cylinder heads stand out:
Thorough Inspection: Every head undergoes a complete teardown, cleaning, and detailed inspection for cracks and imperfections.
Advanced Cleaning: Thermal cleaning for cast iron and high-pressure washing for aluminum ensures a brilliant finish.
Precision Machining: CBN resurfacing, triple-angle valve cuts, and guide installations exceed OEM specifications.
Rigorous Testing: Vacuum tests, tension checks, and pressure tests guarantee performance and durability.
High-Quality Components: New seals, plugs, and rebuilt lifters ensure optimal functionality.
Final Assurance: Each head is inspected, stamped, and stored in a climate-controlled environment.
Wide Availability: Over 2,000 cylinder heads for all makes and models, ready for repair or exchange.