How Much HP Can A 5.3 LS Make?

By Chris Thatcher

Updated Feb 18, 2024

In 5.3 LS Feb, 2024

People talk all the time about their next LS build or doing an LS swap, while others sit there wondering what is so great about the LS platform. It’s plentiful since it’s been the engine platform for millions of vehicles, which also means it’s relatively cheap and there are tons of companies making aftermarket parts and mods.

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    On top of it all, LS engines such as the 5.3 are easy to work on, even for those without serious experience. This is why the 5.3-liter engine is an incredibly popular engine to put in everything from sport trucks to 2nd generation Camaros and even late 70s LS-converted Novas.

    Where We Buy
    We highly recommend using eBay as it provides a secure platform, ensuring protection against scams.
    If you're looking for a used LS Engine to buy, honestly, we buy from eBay. I cannot tell you how many times I have bought a junkyard LS from a local "reputable" Junkyard and got screwed with a bad motor and then they wouldn't warranty it. I buy from Ebay because typically the vendor is more accountable because they don't want bad reviews, they also provide a decent warranty, and worst case, Ebay and Paypal can get involved if necessary.

    Some even swap LS powerplants into Jeep Cherokees, so they are one of the most useful and versatile engine platforms out there

    But just how much horsepower can a 5.3 engine make? We’ve got the answer for you, as well as beginner, intermediate, and advanced mods to get big hp from your next LS project.

    How Much Horsepower From 5.3 LS Engine?

    5.3 LS

    At factory settings and with barebones, stock outfitting the 5.3 L should make about 320 horsepower. This number is not generally seen, however, and most real-world testing puts the 5.3 LS closer to 315 hp.

    With some relatively simple upgrades, you can see an extra 100+ hp, and with some more extreme mods you may see 1,000 hp or more for a short time. If you're asking how much power or how much boost, this is a good place to start.

    What Are Some Bolt-On Options For Easy HP On A 5.3 LS?

    If you are looking to put some easy horsepower mods on your 5.3 liter, you should probably look at bolt-on modifications. These are mods that you can do with tools most people have on hand, and with only a minimal time and experience requirement. The mods in this category can be completed in 30 minutes to 2 hours.

    Performance Cold Air Intake

    Putting a performance cold air intake on your 5.3 LS can add anywhere between 15 and 30 extra horsepower. They work by helping to deliver a much cooler and denser air charge to the intake.

    Underdrive Pulley Kits

    Underdrive pulleys can provide another 15 horsepower since they cut down on the drag put on the engine before it ever reaches the transmission. They also create less wear on the belts and bearings, lowering maintenance needs.

    Fuel Injector And Air Intake Upgrade

    Fuel Injectors are responsible for the supply of fuel to the air intake on top of the cylinder head, and so upgrading your fuel injectors and a good tune can provide a significant improvement to the fuel and power curve.

    Long Tube Headers

    They may seem intimidating, but on the LS engines, headers can be swapped out relatively easily. You will need a gasket and high-temperature sealant, but opening up your exhaust creates less backpressure for your engine, allowing it to run more freely.

    How Do You Maximum Engine Speed?

    For getting how much HP you want (100 hp or more) out of your mods, you will need a little more time, a bit more experience, and in many cases a solid bit of extra change.

    These upgrades will take several hours or more, and will require specialized tools and knowledge of the replacement and tuning process. The power output very well might affect your fuel consumption and exhaust system.

    Upgraded Aluminum heads

    Cylinder heads are one of the most important parts of an engine and choosing the right one can make all the difference in terms of performance and reliability. Upgrading to 799, 243, 317 or any aftermarket LS cylinder heads can add more horsepower

    Mild Cam

    The cam determines the intake and exhaust cycle duration, and running a more aggressive cam can lead to pulling in more fuel and air prior to combustion.

    Engine Tune

    When changing camshafts, the timing of the engine will often need to be adjusted to account for the longer or shorter valvetrain action. A professional tuner can adjust the fuel and air trim levels to increase horsepower significantly.

    What Are More Extreme Ways To Boost HP?

    Want more power solutions on your stock 5.3 l? A few mods can go a long way.

    If you’re still hurting for more ponies, you can get extreme. Leveraging one or more of these mods can easily put your hp above 600, and in some cases they can push you over the 1,000hp mark, requiring things like an improved rear end and transmission.

    The parts alone for these mods can reach several thousand dollars and can take more than a day to get installed and tuned to perfection.

    Forced Induction

    Putting a supercharger or turbo setup on your LS can increase horsepower and lb ft of torque levels, often resulting in increases of several hundred peak power horsepower. Other components will need to be upgraded to be able to handle the power that is created by these mods.


    For the true adrenaline junkies out there, you can even stuff some nitrous into your 5.3. While this may create an additional 100-500 hp peruse, it is short duration and incredibly hard on the engine itself. Engine components such as pistons and crank should be upgraded to handle the surge of power.

    How Much Power Does A Stock 6.0 LS Have?

    Surprisingly the 6.0 LS is larger than the 5.3 LS, but it has a lower stock hp rating and puts out 300 hp @ 4,400 rpm. There is a larger potential for upgrading and expanding the stock 6.0 than the 5.3 LS, but in their stock form, the 5.3 is a little stronger.

    Horsepower From A 5.3 LS

    Now that you know what kind of hp a 5.3 LS can make, you will be well-prepared for your LS project. You should also have plenty of ideas for how to get the power you want from the engines you love.