The Guide to LS6 Camshaft Upgrade. Since Chevy installed the LS6 in the C5 Z06 Corvette, it has been a favorite power plant for high-performance projects. From the factory, the powerful 5.7L V8 produces 385-405 horsepower and 385-400 lb-ft of torque. Nonetheless, everyone who has driven one would tell you that they are begging for more. An LS6 camshaft modification is one of the most common engine mods. Upgrading the stock cam to a performance cam enhances peak horsepower, improves the entire power range, and adds a distinct exhaust tone.
This guide will cover upgrading the camshaft on the LS6 engine, which was available in the C5 Z06 Corvette from 2001 to 2005, and in the Cadillac CTS-V from 2004 to 2005. We’ll start with the basics of what a camshaft does and how the stock cam performs, and then we’ll get into why you might want an LS6 camshaft upgrade and how to pick the best one for your build. Finally, we’ll discuss our top LS6 camshaft picks. Let’s get this party started.
LS6 Camshaft Fundamentals
A camshaft is an essential component of an engine’s valve train. The valve train is responsible for controlling the opening and closing of an engine’s intake and exhaust valves, which allow air and fuel to enter and exit the engine. The camshaft’s function is to control when and how long the valves open and close.
A camshaft is, as the name implies, a long shaft with multiple “cams” or lobes on it. Each lobe corresponds to an engine valve, so an LS6 camshaft has 16 lobes. The LS6 has an overhead valve (OHV) valve train and a “cam-in-block” camshaft. That is, the camshaft is located inside the block rather than on top.
A timing belt or timing chain connected to the crankshaft controls the camshaft. As the camshaft rotates, the lobes make contact with lifters, which push up and down on pushrods. The pushrods are connected to the rocker arms, which are attached to the valves themselves.
The valve is pulled down as the pushrods actuate the rocker arms, allowing/expelling air into and out of the engine. As the pushrods and rocker arms return to their original positions, the valve is pushed back up, closing the intake and exhaust ports and preventing air/exhaust from entering or exiting. A set of valve springs guarantees that the valve remains closed when the rocker arm is not pushed down.
That is how an OHV engine’s valve train works in a nutshell. Check out the video below to see an animated representation of an OHV engine.
Specifications for the C5 Corvette LS6 Cam.
Now that we understand the fundamentals of how a camshaft works, let’s look at the various specifications camshafts have and what they signify for engine performance. As previously stated, the camshaft’s function is to control the timing and duration with which the valves admit air and fuel into and out of the engine. The idea is to get as much air and fuel into the cylinder as possible, and then get the exhaust out of the cylinder as rapidly as possible after full combustion.
Duration, lift, and lobe separation angle are the three most typical camshaft specifications. All of these terms refer to the camshaft’s “cams” or lobes. Larger lobes will result in higher lift and duration, and a larger angle between them will result in a larger lobe separation angle (LSA), but we’ll go into that further below.
Explained: LS6 Camshaft Duration, Lift, and Lobe Separation Angle
The duration of a camshaft is normally measured in degrees and is based on the rotation of the crankshaft. A larger duration indicates that the valve is open for a longer amount of time. For consistency, most camshaft durations are stated in 0.050″ crankshaft rotation increments.
So, for example, a common LS6 camshaft duration may be “intake 220° @.050″, which indicates the crankshaft rotates 220° while the intake valves are open. Because all modern engines have intake and exhaust valves, you’ll typically observe two measurements per cam, one for intake and one for exhaust. Because the intake and exhaust cams are normally open for different amounts of time, you’ll observe two different figures.
The amount of valve opening is determined by camshaft lift, which is measured in inches. A typical LS6 camshaft lift is around 0.550” and, like the duration, has intake and exhaust measurements.
The lobe separation angle specifies the angle between the camshaft’s intake and exhaust lobes. An LSA of 0° indicates that they are both facing the same direction and that the intake and exhaust ports open at the same time. The LSA of a standard LS6 camshaft is 114°, which means that the angle between the intake and exhaust lobe centerlines is 114° apart. LSA also determines when the exhaust and intake valves are open, with a larger LSA indicating more overlap.
What Do LS6 Cam Specs Indicate?
So, what does it all mean? A camshaft with a longer duration and greater lift will allow more air into the engine for a longer period of time, allowing it to produce more power. A camshaft with shorter duration and lift will limit the amount of air entering the engine.
The LSA is also crucial because it indicates the car’s drivability. A narrower LSA produces more low-end torque and more peak torque, but at the penalty of a smaller power band, increased cranking compression, poor idling, and higher cylinder pressures, which increases the likelihood of detonation.
A wider LSA will result in less peak torque and less low-end torque, but it will also idle smoother, have less cranking compression, a longer power band, and lower cylinder pressure – all of which lessens the probability of detonation.
You must balance performance and drivability for all three LS6 specs: duration, lift, and LSA. If you’re building anything for the track that doesn’t need the smoothest idle or the best drivability, a greater duration and lift cam with a moderate LSA would suffice. A more moderate duration and lift cam with a wider LSA will work best if you still require daily driver performance and want to create some extra power.
LS6 Cam Specifications for the C5 Corvette
During its production run, the LS6 employed two distinct profile camshafts. The LS6 debuted in 2001 with a cam that had an intake/exhaust duration of 204°/211°, lift of 0.525″/0.525″, and a 116° LSA. The LS6 used a cam with an intake/exhaust duration of 204°/218°, lift of 0.555″/0.551″, and a 117.5 LSA from 2002 to 2005.
As you can see, the second LS6 cam was significantly hotter due to increased exhaust duration, increased lift, and a somewhat wider LSA. The new hotter cam contributed to the performance boost of 20 horsepower and 15 pound-feet of torque.
When Should I Replace My LS6 Cam in My C5 Corvette?
By far the most common modification is the installation of an LS6 camshaft. A camshaft is more than just a simple bolt-on to boost horsepower. It is a modification to the internal engine that significantly alters how the car functions and handles.
To get the most out of a camshaft modification, you need have at least an improved cold air intake and long-tube headers. These will improve the engine’s ventilation, allowing it to breathe better and perform more efficiently.
The amount of performance added by cam upgrades might vary greatly. Lower profile cams will provide 20-30 horsepower, whereas large cam sets can offer up to 100 wheel horsepower in the correct situation. Keep in mind that the larger the cam, the worse the drivability and idling.
Selecting the Best C5 Corvette LS6 Cam
Now, considering the duration, lift, and LSA criteria we discussed previously, let’s get into ideal LS6 camshaft sizing for your project. For budget builds and those wishing to preserve a largely stock handling profile, cams with a duration of 214°-225° and an LSA of 112°-115° should be considered. Looking in the 226°-240° range with an LSA between 112°-114° will probably be optimum if you want a little more horsepower while still maintaining good drivability.
If you’re seeking to crank up the power and obtain some significant horsepower, and you’re ready to give up some low-load drivability, anything 241° and larger with an LSA between 110°-112° will do. Lift for an aftermarket LS6 camshaft should be in the 0.550″-.615″ range. Higher horsepower builds will typically require more lift, although this is not always the case.
In general, the factory cam will create 400 whp with bolt-ons (cold air intake, headers/exhaust), and cams ranging from 214° to 225° will add 25-50 whp over stock. Cams between 226° and 240° will add 50-75 whp above stock, while cams bigger than 241° will add 75+ whp.
Remember that camshaft performance is governed by duration and lift, thus duration alone will not provide the complete story. While the argument rages on, most individuals believe that lift determines performance rather than length. However, most cams are discussed in terms of duration rather than lift, which is why we provided the above information.
Camshafts are among the most difficult LS6 upgrades to perform. Many folks require 2-3 cam swaps before they find a suitable mix of duration and lift. As previously said, it modifies the way the car drives, which can be both beneficial and negative.
Rest of the LS6 Valve Train Upgrade
You will need to update the LS6 valve train regardless of how hot of a camshaft upgrade you choose. You will need to upgrade to firmer valve springs nonetheless, as the factory springs are hardly adequate. COMP 918 and 921 valve spring improvements, Manley’s Nextek, and Crane Duals are among the most popular LS6 valve spring modifications.
Pushrods will come next. While upgrading the pushrods is not required, it is highly recommended – even with moderate cam changes. The stock pushrods have been observed to flex under heavy loads, indicating that calamity is just around the horizon. Investing in stronger aftermarket pushrods is a low-cost way to ensure maximum performance.
You can also update the rocker arms as a precaution, which is appropriate for higher horsepower builds (800+). Using a rocker arm with a higher ratio than stock can enhance lift/duration and overlap, resulting in more power. Many customers additionally purchase the Trunion Rocker Arm kit, which transforms the rocker arms to roller bearing rocker arms and improves reliability.
Because the factory ones are known to fail, upgrading the timing chain is pretty much typical for any cam upgrade. Many people upgrade the lifters as a precaution while upgrading the cam and pushrods.
With these enhancements, your cam swap will be a breeze. Early LS1 engines also require a new oil pump, but the LS6 has an updated one that eliminates the need for one.
LS6 Pistons with Flycutting
You may need to fly cut the LS6 pistons for increased valve clearance depending on the size of your camshaft modification. Fly cutting is the process of creating pockets on top of the pistons to allow the valves to go down further. Fly cutting is required on long duration, high lift, and low LSA cams. Cams more than 240° on the LS6 will likely necessitate fly cutting.
Advantages of an LS6 Camshaft Upgrade
The following are the top LS6 camshaft upgrade advantages:
- +25-100 horsepower at the wheels
- wheel torque +25-100
- Broadened power band
- Exhaust has a distinct “chop-chop” sound.
The additional power is by far the most significant advantage of a camshaft modification. Depending on the cam profile you select, you can add 25-100 wheel horsepower and torque to your build. While some argue that cams only make a difference at the upper end, this is simply not true. In general, the entire power spectrum will become wider. On huge cams, where some low-end torque is lost, the top-end curve is still more beneficial.
Cams are excellent enhancements for naturally aspirated engines, but they can also be useful in forced induction builds. For the correct turbo construction, well-designed and tuned cams can boost spool while retaining more peak power.
The characteristic exhaust note produced by cams is another “benefit” of an LS6 cam modification. While small cams will maintain the exhaust sounding reasonably stock, larger cams will provide the well-known “chop-chop” sound. Most cam swaps on LS engines sound amazing, especially via long-tube headers.
Tuning the LS6 Camshaft ECU
Finally, we will discuss ECU tuning for your camshaft modification. Smaller cams can be used without tuning, but the larger the cam, the more difficult it is for the ECU to compensate. If the ECU is unable to compensate, the engine will struggle to idle properly and will misfire.
It is a good idea to get your ECU adjusted after upgrading your cam to enhance performance while guaranteeing reliability. You don’t want to spend $600 on a cam upgrade simply to have an undriveable car.
Top 3 LS6 Camshaft Upgrades for the C5 Corvette
The following are the top three LS6 Camshaft upgrades:
- Motorsports at Livernois
- Cams COMP
- Texas Performance and Speed
1) LS6 Cam Upgrades by Livernois Motorsports
The Stage 2, Stage 2R, and Stage 3 Camshafts from Livernois Motorsports are first on our list. Livernois Motorsports is a well-known name in the LS engine construction market. They’ve been making LS6 parts since the engine was produced by GM, and they have a great reputation for quality.
For the LS6, Livernois Motorsports provides three distinct camshafts: Stage 2, 2R, and Stage 3. With a duration of 232°, lift of 0.595″, and LSA of 114°, the Stage 2 cam is intended for modest street builders who want some extra horsepower. The Stage 2R cam from Livernois trades drivability in exchange for a length of 236°, lift of 0.602″, and LSA of 113. The Stage 3 cam sacrifices drivability as well. It has a short duration of 224°, but a larger lift of 0.612″ and an ideal LSA of 114.
For moderate builds, we recommend the Stage 2 cam. You can go to Stage 2R and 3 if you’re ready to trade drivability for power. Despite having a longer duration, the Stage 3 has much more lift and will most likely provide you with the greatest horsepower. All of them are excellent selections that may be combined with their LS6 cylinder head for maximum performance.
2) LS6 Cam Upgrades by COMP Cams
COMP camshafts are our next recommendation for LS6 camshafts. COMP cams is yet another industry-leading camshaft producer with a strong reputation. Some of the most powerful LS builds on the market today feature a variety of COMP cams. They have an enormous range of LS6 cams for almost any build.
COMP cams for the LS6 range from moderate to aggressive. Their lower profile cams have a duration of 216°/220°, a lift of 0.525″/0.532″, and an LSA of 114. Their best performance cams have a duration of 238°/240°, a lift of 0.605″/0.609″, and an LSA of 112. COMP has six different LS6 camshafts with durations between those two.
The COMP cams are best suited for intermediate builds aiming for 425-500 wheel horsepower naturally aspirated. The larger cams will begin to sacrifice drivability, but this should not be too severe. These cams deliver excellent mid-range and top-end performance.
3) LS6 Cam Upgrades from Texas Speed and Performance
Texas Speed and Performance is our ultimate recommendation for an LS6 cam modification. TSP hasn’t been around as long as Livernois or COMP, but they have a solid reputation for quality.
TSP, like COMP Cams, offers a wide range of camshafts, some of which are designed for both naturally aspirated and boosted applications. Most TSP LS6 camshafts have a lift of at least 0.600″, indicating that they all provide some performance. Their moderate cams will gain you 20-35 horsepower, while their most powerful cam sets will gain you 75+ horsepower. To assist you with sizing for your build, they provide small, mild, and max effort cams categories.
The TSP is suitable for almost any build level. Their smaller cams will offer adequate power increases while keeping drivability. Their larger cams will provide plenty of power, but drivability will suffer as a result. Overall, regardless of build, the TSP cams are great choices.
Related : The Guide to Upgrading the Chevy LS3 Intake Manifold
Summary of LS6 Camshaft Upgrades
Upgrading the camshaft on the LS6 is a great performance upgrade that results in significant horsepower gains. Of course, as previously stated, this is not a little tweak, and it has a significant impact on how the LS6 operates. Still, on the appropriate builds, improved cams will make a huge impact in your power band.
We looked at various potential camshaft options for your LS6 build in this article. When selecting your cams, keep our sizing guidance in mind, but it’s also a good idea to speak with the camshaft manufacturer directly. Explain your power goals to them and collaborate to locate the optimal cam for your setup. Our recommendations will help you locate what you’re searching for, whether it’s something light and steetable or something massive and race-only.