This article will explain all you need to know about the 799 heads.
The type of cylinder mounted on an engine plays a significant role in determining its performance.
However, some cylinder heads are built to minimize the engine’s horsepower. On the contrary, some cylinder heads boost the engine’s performance due to their unique architecture and design.
The 799 head is one of them; kindly read on as we discuss the 799 cylinder head and what makes it a perfect fit for your porting needs.
So, I’ll provide a complete analysis of the 799 heads to help you determine what makes them a perfect fit if you need to port your cylinder.
What Are 799 Heads?
Some of the newest cylinder heads available on the car components market are 799 heads.
They are the ideal option for a porting job since they provide good performance with more horsepower.
The most recent model uses the semi-permanent mold technique to create these 799 heads. The aluminum heads of the 799 heads can endure high temperatures.
Aluminum is a great material since it is strong but lightweight. In terms of triangle casting, they are comparable to 2004 LS2 heads, but unlike the 243 heads, they don’t need to be cleaned.
Users of 799 heads can employ vacuum and pressure testing to check the valve seating of the 799 cylinder heads. It aids in ensuring the dependability of the cylinder head’s channel. Truck engines with 5.3L and 4.8L displacements were the LS engines built with 799 heads.
The LS 799 heads advanced architecture and cathedral-shaped exhaust port enabled them to provide remarkable truck engine performance.
799 LS Heads Specifications
Ported 799 heads ensure high-quality performance and efficiency. However, before porting, you should make yourself aware of the specifications.
For instance, the 799 cylinder heads come with a smaller combustion chamber than its counterparts. So porting to 799 LS heads would mean milling the cylinder heads to cover up for the bigger size of the former combustion chamber.
#1. Material Make.
The 799 heads have an aluminum build that can withstand high temperatures. Aluminum is a good material of choice because it is lightweight yet durable.
#2. Intake Port Shape.
The intake port forms the final part of the air induction system in an engine. It connects the intake manifold with the cylinder heads.
The 799 LS heads have a cathedral-shaped intake port. The shape is designed to increase airflow and power.
#3. Exhaust Port Shape.
The exhaust port in an engine is just as important as the intake. It is responsible for removing the spent gases from the cylinders.
The 799 LS heads have a D-shaped port. Typically, the D-shaped port helps increase the flow of exhaust gases.
#4. Combustion Chamber Size.
The combustion chamber is the space in the cylinder where the air/fuel mixture is ignited. The size of the chamber can affect power and efficiency.
The 799 LS heads have a smaller combustion chamber of 64cc. The configuration allows for a higher compression ratio, resulting in more horsepower.
#5. Intake Valve Size.
The valves are responsible for letting air and fuel into the cylinder and the exhaust from that combustion out of the cylinders. The size of the valves affects the performance of an engine. The 799 LS heads have 2.00-inch intake valve.
#6. Exhaust Valve Size.
The exhaust valve is responsible for expelling the burnt gases off the combustion chamber of an engine after the power stroke.
Therefore, the size of the exhaust valve is an essential factor in determining how much power an engine can generate. The exhaust valve should ideally be 85 percent of the size of the intake valve.
The 799 LS heads have a 1.55-inch exhaust valve size.
#7. Intake Port Volume.
The intake port volume indicates the total amount of air that the engine can pull into the cylinders during the intake stroke. A larger port volume results in more power, decreasing fuel economy. The intake port volume for 799 LS heads is 209 cc.
#8. Exhaust Port Volume.
The exhaust port volume specifies the total amount of exhaust gas that can flow out of the cylinders during the exhaust stroke. The exhaust port volume for 799 LS heads is 74 cc.
#9. Compression.
In an internal combustion engine, the compression ratio is the ratio between the volume of the cylinder and combustion chamber at their maximum and minimum values.
In other words, compression ratio can be defined as the ratio of the volume of the cylinder and its head space when the piston is at the bottom dead center (BDC) and to the volume when the piston is at the top dead center (TDC).
799 cylinder heads have a compression ratio of 9.5:1.
What engine has 799 LS Cylinder heads?
The aluminum 5.3-liter truck engine has 799 heads. The 799-cylinder head distinguishes the 5.3L from other engines due to the compression ratio. In addition, the 799 heads deliver increased power output on the 5.3-liter truck engine.
Although the cylinder heads were made originally for the 3.90-inch bore, they fit perfectly on 5.3L and 4.8L blocks (3.78-inch bore). 799 heads on 5.3 engines are a perfect fit.
Problem Of 799 Heads
The size of the combustion chamber is the major challenge with swapping to 799 heads. Since the cylinder heads come with a smaller combustion chamber, you will have to mill the cylinder heads to a minimum of 0.025 to cover up for the former bigger combustion chamber size.
Inasmuch as porting to 799 heads comes with an advantage of increased horsepower due to increased compression, you must ensure to consider both the pros and cons before swapping the cylinder heads.
If you’re contemplating 799 heads vs. 706, they offer more advantages compared to 706 heads, irrespective of the common challenge with 799 heads.
Choosing the Right Cylinder Heads
For many people, selecting suitable cylinder heads can be pretty tricky. For example, should you opt for the Chevy 799 heads, or are the LS 243 cylinder heads better?
Are the 799 heads on LS1 interchangeable? If you’re uncertain, here are a few factors to consider before going for 799 heads.
#1. Engine Displacement.
The first thing you’ll want to consider is the engine displacement, also known as cc. The 799 heads cc are smaller compared to its counterparts because of its smaller combustion chamber.
It plays a significant role in selecting suitable heads because it will ultimately determine the compression ratio.
While large combustion chamber reduces the compression ratio, smaller combustion chamber produces more power due to increased compression ratio.
#2. Cylinder Head Material.
The material of the cylinder heads is another essential feature. Many ported 799 heads are made from aluminum, which is a good choice because it’s both solid and lightweight. However, you may also find some heads made from cast iron.
These are usually reserved for larger engines because they can handle the increased displacement and power. But, they are also much heavier than aluminum heads, which can negatively affect performance.
#3. Porting and Polishing.
Another factor to consider is whether or not the heads have been ported and polished. Porting and polishing help improve airflow by opening the intake and exhaust ports. You’ll want to consider it if you’re looking for increased performance.
However, it’s important to note that porting is a delicate process. If it’s not done correctly, it can decrease performance.
#4. Type of Vehicle.
You also need to consider the type of vehicle you have. If you’re going to be driving on the street, you won’t need as much power as someone who will be racing their car.
You’ll also want to consider how often you drive and what kind of conditions you’ll be driving.
For example, if you only drive on the weekends, you can probably get away with a less powerful engine. However, if you’re planning to drive in hot weather or at high altitudes, you’ll need an engine that can handle harsh conditions.
#5. Compression Ratio.
Finally, you’ll want to take the compression ratio into account. A higher compression ratio means more power with less fuel in the cylinder and fewer exhaust gases. But, it also means more heat inside the engine.
Keep the above-mentioned points in mind when choosing the right cylinder heads. Take your time and compare your options before making a decision.
Is 799 Heads Any Good?
Yes, they’re one of the best cylinder heads you can purchase in the automotive aftermarket.
In comparison, the 799 heads surpass the 706 heads emission by 20 CFM, a cathedral, and a D-shaped port design. Also, the decreased combustion chamber gives room for higher compression and horsepower.
FAQs.
Q: What CC are 799 heads?
The 799 head cc is pretty smaller compared to some others. This is because the cylinder heads come with 64cc combustion chambers. It is vital to note that combustion chamber size plays a significant role in either increasing or reducing the compression ratio.
While a smaller combustion chamber increases the compression ratio, the bigger one reduces the compression ratio. The implications differ for both scenarios. An increased compression ratio results in more power output.
Meanwhile, a reduced compression ratio results in a cooler burning temperature. This automatically leads to inefficient combustion with reduced power output.
Q: Are 799 heads Cathedral Port?
Of course, the 799 heads are designed with a cathedral shape intake port. They come with smaller chambers compared to some of their counterparts with rectangular ports. The compression ratio of 799 heads can cause a leap in a vehicle’s power output.
The power output can swing up to around 3 – 4 percent, delivering about 25 horsepower (hp). This can positively impact a vehicle’s engine performance and efficiency.
If you are considering a porting job on your vehicle, 799 head is a perfect choice, at least for the guaranteed power output that results from the kind of intake port it features.
Q: What year do trucks have 799 heads?
799 heads came on trucks manufactured around 2005 and above, as well as newer models of 5.3 and 4.8-liter trucks, come with 799 heads. However, Chevy unveiled the L20 4.8-liter engine, which had the 799 cylinder head in 2010.
The L20 4.8-liter engine had an A on the VIN. It was actually the 8th digit of the vehicle identification number. The 799 heads have been amazing on the 4.8 and 5.3-liter truck engines since inception. You may want to check out for your next porting job.
Q: What LS engine comes with 799 heads?
5.3L and 4.8L truck engines are LS engines designed with 799 heads. The cylinder heads perform amazingly on the truck engines. They are built with sophisticated architecture, including a cathedral-shaped port with smaller combustion chambers.
The smaller combustion chambers help to reduce the compression ratio, which in turn boosts combustion efficiency for increased power output. 799 heads are known for leaping power output by 3 to 4 percent, which automatically leads to a horsepower boost up to 25 hp.
Final Words
A lot has been unveiled, about 799 heads. The cylinder heads are designed to offer increased horsepower due to the increased compression, which results from the smaller combustion chamber.
However, ensure to consider the pros and cons of swapping your current cylinder heads to 799 heads before a porting job. Meanwhile, some vehicle enthusiasts and professional auto mechanics opine that swapping to 799 heads is worth it.