Used 799 Cylinder Head #012
In stock orders typically ship within 1 business day.
Used GM LS 799 Cylinder Head, Cathedral Port
This is a used OEM-style GM LS 799 cylinder head. The 799 casting is a cathedral port LS cylinder head commonly found on later 5.3L GM LS-based engines and is often considered very similar in performance to the well-known 243 casting.
799 heads are one of the more desirable factory cathedral port LS heads. They offer strong factory airflow compared to earlier 4.8L / 5.3L truck heads such as 706 and 862, while still using the factory cathedral port layout.
With an efficient combustion chamber and good OEM airflow, 799 heads are a popular choice for naturally aspirated LS builds, cammed street engines, mild boost combinations and performance upgrades where a factory GM casting is preferred over aftermarket cylinder heads.
Important Condition Information
This is a used cylinder head and condition may vary between individual units. Some heads may be more complete, while others may be missing valves, springs, retainers, seals, bolts, plugs or other small parts.
Some used heads may have cosmetic wear, dirt, oxidation, gasket residue, broken bolts, damaged threads or other defects. Please see the product pictures carefully for actual condition and included parts.
Important Fitment Information
This 799 cylinder head is intended for GM LS cathedral port applications. It is commonly associated with later 5.3L LS engines and may also be used in other LS-based combinations where the chamber size, valve size and cathedral port layout are suitable.
Always compare the casting number, port shape, combustion chamber style, valve size and bolt pattern with your original cylinder head before ordering.
Suitable For
- GM LS 799 cathedral port cylinder head applications
- Later 5.3L LS-based engines using 799-style heads
- 5.3L, 5.7L, 6.0L and compatible LS-based performance builds
- Cammed street engines and naturally aspirated LS builds
- Mild turbo or supercharged LS combinations where this chamber and port style is suitable
- Stock replacement, repair work and performance LS upgrades
Product Details
- Condition: Used
- Casting number: 799
- Type: LS cathedral port cylinder head
- Application: GM LS-based engines with cathedral port cylinder heads
- Common engine applications: Later 5.3L LS engines and compatible LS builds
- Combustion chamber: Approx. 64.5cc
- Intake port volume: Approx. 210cc
- Exhaust port volume: Approx. 75cc
- Intake valve size: 2.00 inch
- Exhaust valve size: 1.55 inch
- Quantity: Sold each
Typical Stock Flow Numbers
| Valve Lift | Intake Flow | Exhaust Flow |
|---|---|---|
| .100" | 62 cfm | 57 cfm |
| .200" | 126 cfm | 108 cfm |
| .300" | 184 cfm | 143 cfm |
| .400" | 224 cfm | 163 cfm |
| .500" | 251 cfm | 176 cfm |
| .550" | 256 cfm | 180 cfm |
| .600" | 257 cfm | 183 cfm |
This is a used internal engine component and may show normal signs of previous use. The cylinder head is sold as pictured, so please review all images to confirm condition, completeness and any visible defects before ordering.
If you are unsure whether this 799 cylinder head is correct for your engine, compare it with your original part before ordering or contact us for guidance.