Cylinder heads are vital for engines as they affect the engine’s performance. They impact the airflow, power, efficiency, reliability, etc. Among all known cylinder heads, the 799 and 862 are commonly used in GM vehicles. But if you compare 799 vs 862 heads, which one is likely to turn out better?
The 799 heads are usually used in high-performance GM vehicles. These heads have larger ports and valves compared to many other LS heads, and they are reliable if you need to increase engine horsepower and performance. On the other hand, the 862 head is commonly used in GM truck engines, but they do not perform as well as the 799 because of their smaller ports and valves.
The 799 and 862 heads are similar in some ways while also having many differences. You can find more about them in the rest of the article.
799 Vs 862 Heads: Comparison Table
|Compatible Engine||4.8L, 5.3L, 5.7L, or 6.0L||LR4, LM4, and LM7|
|Intake Port Shape Design||Cathedral||Cathedral|
|Exhaust Port Shape||D-Port||D-Port|
|Exhaust Valve Diameter||1.55 inches||1.55 inches|
|Exhaust Port Volume||74 cc||70 cc|
|Intake Valve Diameter||2.00 inches||1.89 inches|
|Intake Port Volume||209 cc||200 cc|
|Combustion Chamber Volume||64 cc||61.15 cc|
|Cost||More expensive||Less expensive|
799 Vs 862 Heads: Detailed Comparison
Both 799 and 862 heads are the essence of high-performing engines. But they have certain feature differences that make them perform slightly differently than one another. So let’s see the detailed comparison of the two to understand their differences or similarities more clearly.
It is a good thing that both the 799 and 862 heads are made of high-quality aluminum. Because the perk of this material is that it is robust, durable, and can withstand high temperatures. Moreover, aluminum is an ideal choice to ensure the product made from it is lightweight.
The 799 head is designed and made to be compatible with high-performing LS engines, such as 4.8L, 5.3L, 5.7L, or 6.0L, etc. These vehicles require maximum airflow, making the 799 head an ideal choice. On the other hand, the 862 head is compatible with LR4, LM4, and LM7 and such engines where low torque is more essential than better horsepower.
Combustion Chamber Volume
The 799 has a combustion chamber volume of 64 cc. It is slightly larger than that of the 862, which is 61.15 cc. It is important to pay attention to this feature when getting cylinder heads for your vehicle because the volume affects the engine’s compression ratio.
Exhaust Port Volume And Valve Diameter
The exhaust port volume plays an important role in the engine’s exhaust airflow. In this case, the 799 has a larger exhaust port volume, which is 74 cc, whereas the 862 has a 70 cc exhaust port volume. However, both 799 and 862 have 1.55 inches of valve diameter.
Intake Port Volume And Valve Diameter
The intake port volume and valve diameter do determine how well the engine’s airflow and power will be. And as the 799 head is made for a high-performing engine, it has a larger volume and diameter of 209 cc and 2.00 inches. On the other hand, the 862 head has an excellent 200 cc intake port volume and 1.89 inches valve diameter, which is almost as good.
The cost of these two types of heads does make a huge difference. Since the 799 is for high-performing engines and also has better features, it is naturally more expensive. On the other hand, the 862 head is a more affordable option.
Pros And Cons of 799 Heads
Here are the pros and cons of the 799 heads-
- Made with durable aluminum
- Lightweight cylinder heads
- Suitable for high-performing engines
- Larger intake and exhaust port volumes increase airflow
- Larger intake and exhaust valve diameters improve performance
- More expensive
- May require modification of some engines to make it compatible
Pros And Cons Of 862 Heads
Here are the pros and cons of the 862 heads-
- Made with durable aluminum
- Lightweight cylinder heads
- Cost-effective option
- Excellent combustion chamber volume increases the compression ratio
- Smaller intake and exhaust port volume
- Smaller intake and exhaust valve diameter
- Not suitable for high-performing vehicles
Frequently Asked Questions
Q. Can I swap 799 heads onto an engine that came with 862 heads?
Yes, one can swap 799 heads onto engines that originally came with 862 cylinder heads. However, depending on the engine type, some modifications may be needed, which can add extra expense.
Q. How much do the 799 and 862 heads cost?
The cost of the 799 and 862 heads vary depending on their models and retailer or suppliers. Nevertheless, the 799 heads are more expensive than the 862 ones.
Q. How long do they last?
The longevity of the heads depends on a few factors, such as their material, usage, build quality, etc. As the 799 heads are made for high-performing and aggressive engines, they go through more stress and maintenance and end up with shorter durability. On the other hand, the 862 heads usually go through less stress and last longer than the 799 heads. Also, Know about how long does fluid film last
Q. What vehicles are the 799 and 862 heads used in?
Both 799 and 862 heads are designed to be compatible with different GM or General Motors vehicles. They usually go in various GM vehicles, such as Chevrolet Silverado and Tahoe, Cadillac Escalade, GMC Sierra and Yukon, etc.
So, after discussing 799 Vs 862 heads, which one should be a better choice? Well, the decision depends on various factors, such as the head’s features and specifications, your vehicle engine type, and whether you want it for on or off-road engines.
The 799 heads, as a high-performer, seems more suitable, but it has a shorter lifespan and is more expensive. And as for the 862 heads, it is cost-effective, more durable, and suitable for street-driven vehicles.
That is why it is best if I leave the decision up to you. Choose wisely!