Home | Auto Detailing | 243 Heads – Meaning, Features, Problems and Important

243 Heads – Meaning, Features, Problems and Important

February 21, 2024 | Victor Lukasso

This article will give you all you need to know about the 243 Heads, including their features, advantages, and importance.

Head porting helps improve a vehicle’s power gain, mainly when its professional mechanic carries it out.

One of the good features of cylinder heads like the 243 heads is that it allows enough ventilation and fuel to get into your car’s cylinder, providing faster combustion and smooth exhaustion.

The 243 Head is one out of the seven different versions that General Motors produced the LS engines.


This post will show you why the 243 cylinder heads are one of the best to select from.

What are 243 Heads?

Cast flash commonly happens while casting cylinder heads out of iron or aluminum alloy. This flaw develops due to metal leaking from cast joints and contact between the substance and the mold’s base while it’s still molten.

The cylinder valve seat and other cuts that were necessary for the cylinder head layout are milled out using CNC machining once the foundation material for the cylinder head is created. A rough cylinder head is produced when the design is finished.

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Fluid passes through the head area and into the cylinder utilizing the valve throat as a channel, depending on the condition of the cylinder head.

The cylinder head must be machined to reduce the number of rough patches or minor constraints that can impair the fluid flow into the corresponding cylinder to achieve an adequate fluid flow that yields maximum performance.

The finer intake and quicker discharging from reduced fluid flow turbulence will increase power output. The 243 head porting is crucial for this reason.

The 243 cylinder heads from GM are third-generation cylinder heads created for performance applications, V8 trucks, SUVs, and vans. They are frequently known as LS6 heads.

The cathedral-shaped inlet ports and D-shaped exhaust on the 243 cylinder heads contribute to better air and fuel intake, smooth burning, and quicker exhaust. Improved horsepower is produced. As a result, they are leading to greater effectiveness.

Features of the 243 Heads

Some notable features of the 243 heads distinguish them from other cylinder heads.

These features contribute significantly to its ability to fit into different engine models.

Weight  26.0 lbs   
Material  Aluminum    
Intake Port Shape  Cathedral   
Combustion Port Shape  D Shaped   
Intake Port Volume  210 cc   
Combustion Port Volume  75 cc   
Combustion Chamber Volume  65 cc   
Valves  8   
Cylinders  4   
Drivetrain  OHV, 16 Valves of 2 per cylinder   
Price  $300   
Cylinder Block     
Rotating assembly     
24x Ignition System     
Horsepower  20 HP   
LS engines with 243 Heads  Engines built from 2001 – 2006 has 243 heads   
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Common Problems with 243 Heads

Over time, particles that can clog the fuel filter may accumulate in the fuel tank. To overcome this issue, it would be necessary to clean the fuel system with a fuel cleansing system frequently.

Are 243 Heads any Good?

The 243 head has better casting and a narrower chamber for more excellent compression. They flow more smoothly and can generate more than 5% of their horsepower from flow alone.

Buying new 243 heads is ideal for the porting job if you want to undertake cylinder head porting on your car. Power production increases when the 243 heads are combined with a firm can and an excellent valve lift. If searching for 243 heads for sale, please get in touch with a local dealer or order online.

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Did the 5.3 come with 243 heads?

Of course, today’s 5.3 and 4.8 both have 243 heads that are factory-designed. 243 heads were included in the LS6 engine produced between 2001 and 2006. You can determine the 243 heads on the 5.3 by examining the three-digit stamping next to the valve cover.

The Sierra 1500 and Silverado from GM produced between 1999 and 2013 had 243 heads. The cylinder heads carried by vehicle engines allow them to generate such high power levels with excellent productivity and effectiveness.

What’s better? 243 or 706 heads

Experiments have proven the 706 cylinder heads are more effective in output production than the 243 heads.


The 243-cylinder head is the ideal option if enhanced horsepower with exceptional power output is what you’re after. In the meantime, you must speak with a skilled vehicle mechanic well-versed in porting jobs.

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Meet Victor Lukasso, the owner of V. Auto Basics. Through this blog, Victor Provides Insights on the latest tips, maintenance, repair, and techniques in the automotive world.