Home | Auto Detailing | 706 Heads – What is so Special?

706 Heads – What is so Special?

February 21, 2024 | Victor Lukasso

This article covers all you need to Know about the cylinder head called the 706 heads.

The fundamental components of an engine – cylinder heads – are crucial to the effective functioning of a vehicle. Choosing the proper cylinder head for your car is also vital since it determines the engine’s performance and endurance.

Although many cylinder head options are on the market, only a few offer dependability and efficiency at a reasonable price. Given this, Chevy 706 LS Heads ensure a durable engine build for your vehicle.

All-new stainless swirl polished 2.00, 1.57 valves, new fasteners, spring seats, and valve seals are included with Chevy 706 Heads, along with new springs for up to.650 lifts.


The heads have been cleaned, taken apart, and pressure checked, and all valve stems have been changed per the manufacturer’s standard.

Among several cylinder heads, the 706 is a reliable performer that maintains the proper combustion ratio. These rebuilt cylinder heads provide substantial power gains at a reasonable price, thanks to the improved combustion chambers and high-velocity port technology. If you have the money, you may upgrade the 706 LS heads with bigger valves for superior efficiency.

Recommended:  317 Heads – All you Need to Know

Continue reading, as we’ll show you further specifications that make the 706 cylinder heads unique.

706 Heads Specs

High-performance cylinder heads like the Chevy 706 LS Heads provide a ton of power at an unbelievable cost.

They are the most cost-efficient and efficient remanufactured cylinder heads available, and they may be used to produce 4.8L, 5.3L, or even 6.0L LS engines.

Their tiny cross-section reveals a high-velocity, smaller-volume, excellent-flow runner design.

The LS 706 cylinder heads, which have been on the market for a while, are ready to use immediately and produce high-performing engines.

Numerous dyno tests have demonstrated the performance. The ported 706 heads also work with various Chevrolet-built automobiles of multiple models.

How to Cast 706 Cylinder Heads

The LS 706 Heads were installed on several Chevy models and paired with the powerful LM7, LR4, and LM4 5.3 engines. These cathedral-port factory high-geared cylinder heads have been rebuilt by an engine specialist at a significantly lower cost, making them the best available cathedral-port factory heads. The details are as follows.

  • The intake valve size is 1.89, while the exhaust valve size is 1.55.
  • 197 cc for the intake and 69 ccs for the exhaust ports.
  • 61.5 cc in the combustion chamber
Recommended:  6 Signs of a Cracked Cylinder Head

Why Cast 706 Heads?

  1. Most powerful, economical, and efficient
  2. Superior in terms of dependability and performance to 862 heads
  3. Excellent flow that outperforms 317 heads and is appropriate for various designs
  4. Have more restricted chambers that prevent compression loss
  5. Abundant and easily accessible in the market

Continue reading as we compare the 706 heads with other cylinder heads.

862 vs 706 Heads

The Chevy 706 LS Heads are superior to the most popular 862 heads, sand cast, and produced using semi-permanent molds (SPM). Although the SPM approach is more reliable, porting 862 heads eliminates their distinction. However, porting is expensive; therefore, casting 706 heads in stock form is the best option.

706 Heads vs 317 Heads

Due to their better ports, 317 heads are frequently preferred over 243 and 799 heads, two more expensive models. However, the bigger 71.06cc combustion chambers of 317 heads will reduce performance, particularly on a normally aspirated engine. Also, with their superior ports, 317 heads experience a net horsepower loss due to this compression loss.

Recommended:  How to Put a Piston in a Cylinder Without a Ring Compressor

Even with their slightly bigger valves, the 706 heads were equivalent to 20 horsepower and 15 pound-feet more than the 317 heads, according to dyno tests on an LM7 5.3L. Milling the 317 heads down is possible, but the process is expensive.

Despite possessing narrower valves than 317 heads, 706 heads are highly effective at maintaining the perfect compression ratio.

706 Heads vs 799 Heads


The preferred cylinder heads of the present period are the 706 heads. They work well and offer the best value for your money while standing out from other heads.

The efficiency of the cylinder heads and the injection system significantly impact the hp, torque, and accelerator response of a vehicle.

Therefore, LS 706 heads are the best option for a high-performance car.

As an Amazon Service LLC Program Associate, V. Auto Basics earns from qualifying purchases. See Our Affiliate disclaimer.


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.