LS Cam Swap Options That Don’t Require Changing Valve Springs

The camshaft inside your engine is a simple piece of your automotive puzzle. Let’s face it, it is a shaft with bumps on it. It’s positioned above the crankshaft and under the intake and is linked to the rotating mass of the crankshaft and pistons via a timing chain and gears. The configuration of those bumps—the technical term is lobes—defines how the performance aspect of the engine is rated (stock or performance-oriented).

By determining when a valve opens, how long it stays open, and when it closes during a single rotation is how the camshaft regulates/develops/determines how much power is made. It also dictates where in the engine’s RPM range this power is “optimized.”

LS Cam

Increasing lift is an easy way to introduce more air into the cylinders, but if the cam holds the valves open longer (add duration), the effect is similar. Duration is measured in degrees of crankshaft rotation. According to Will Vance, the LS engine is very happy with a duration at .050-inch lift of around 230 degrees.

Since we are discussing camshafts, we decided to take a look at Lunati’s latest LS offerings. Lunati has been in the power-making business for decades, which means the folks there have been designing and grinding camshafts longer than I can even remember.

Although all engines require a camshaft, when Chevrolet sprang the LS engine on enthusiasts, the new engine made a drastic departure from the traditional small-block’s breathing characteristics. We asked Will Vance of Lunati if the LS engine requires any specific design and/or lift and duration needs that are different than a traditional small block Chevy.

“Well, yes and no,” he says with a chuckle. “It quite honestly comes down to the efficiency of the LS platform through its head design. In stock form, the LS head flows unbelievably well. These engines really respond to camshaft swaps. Now, a typical old-school SBC with a decent set of heads still only flows so much and will only want ‘X’ amount of camshaft. However, a bone stock 5.3-liter LS engine loves what would be considered a huge cam (when compared to an old-school engine). Generally, the thought process of bigger is better does pretty much apply to the LS engine. Of course, everything has limitations, but the LS platform loves a 230-degree duration—or more—at .050-inch with not much else done to the engine. Again, Not so much they need a specific lobe design, but the heads allow the engine to take advantage of a healthy cam and not be over-cammed.

Unsprung Power

When it comes to cam swaps, the change usually requires an upgrade of valve springs as well. For some enthusiasts, this is a bit tricky as some enterprising hot rodders lack the tools necessary to properly install the springs. Luckily, Lunati has options for these people.

“Our Voodoo Low Lift (LL) series of cams are derived from our ever-popular, tried-and-true lobe design of the Voodoo series of cams,” says Will. “These lobe designs are an asymmetrical design, that has a really fast opening ramp to really pull in some air and build a ton of power while having a softer (not slow) closing ramp, which sets the valve down gently. This allows better valvetrain stability and way more life out of the springs. Basically, it doesn’t beat your valve train to death.”

LS cam

Many enthusiasts are not interested in swapping valve springs, and with the Lunati LL cams, they do not have to.

The Lunati Voodoo LL-series camshafts for 1997 through 2015 engines, is a great entry-level stick that gives improved power while still allowing the use of factory valve springs—any factory LS valve spring. “The LL designation spring is designed for the aftermarket consumer who really wants to take advantage of the LS powerplant they have, yet does not want to get into changing springs,” affirms Will. “This is a bolt-in deal that on average, has seen in excess of 65 horsepower gains.” In any engine, that is a serious increase in power.

According to Lunati, these are the most powerful, factory-spring-compatible camshafts on the market, and blend ease of installation with outstanding performance. The LL springs are available in four stages to allow users to select the best fit for their application and performance goals. The Voodoo LL-series lobes have been optimized to allow engines to spin upwards of 6,200 rpm with excellent dynamics, even—as mentioned—with factory-designed valve springs.

“We offer these in stages to simplify the ordering process of what the customer may need for their application,” Will states. We have four stages of the LL cam, two of which do not require a spring or torque converter change. The third and fourth stage cams are the bad boys of the bunch and do require a stall converter or be used in a manual application.”

Power In Stages

The Stage I hydraulic-roller cam features a good idle, excellent low-end torque, and mid-range horsepower. It is perfect for any truck, SUV, or heavier car, where off-idle responsiveness and great torque between 2,000 and 4,000 rpm is a must. It delivers an advertised duration of 261/273 degrees and an at .050-inch lift duration of 211/223 degrees. It has a gross valve lift of .542/.542-inch and an LSA/ICL of 112/108 degrees. The suggested RPM range is 1,200 to 5,600.

The Stage II camshaft is great in high performance 4.8, 5.3, and 5.7-liter applications with automatic transmissions or vehicles weighing over 3,500 pounds. As Will alluded, this is the largest LL grind that can perform well with a stock converter. The advertised duration rolls over at 269/281 degrees, while the at.050-inch duration comes in at 219/231degrees. Valve lift is .542/.542 inch and the LSA/ICL is 113/109 degrees. The recommended RPM range is 1,500 through 6,200.

LS Cam

The Voodoo Low Lift cams are derived from the lobe design of the Voodoo series of cams. The lobe designs are asymmetrical with a fast opening ramp and a softer closing ramp.

If looking at the Stage III stick, this hydraulic-roller cam is best suited for use in modified 5.3 and 5.7 or larger displacements with a manual transmission or a 3,000-plus stall converter. This is the best all-around performance Voodoo LL cam for modified applications, especially those that will see time on the drag strip. The advertised duration is 277/289 degrees while the At .050-inch lift numbers are 227/239. The gross valve lift measures just slightly more than ½-inch, at .542/.542-inch. Finally, the LSA/ICL is 114/110 degrees. The recommended RPM range is 1,800 through 6,200.

Those who feel the Stage IV camshaft is the right choice, need to consider that this cam is best used in highly modified 6.0-liter or larger applications with manual transmissions or automatic cars with a 3,000-plus stall converter. It is ideal for budget-friendly race cars and serious street applications. The advertised duration lingers for 285/297 degrees while duration at .050-inch is 235/247 degrees. Valve lift opens for .542/.542-inch, and the LSA/ICL is 115/111 degrees. This cam is designated to be right at home in an RPM range of 1,800 to 6,200.

Springing Into Action

If you’re not worried about changing valve springs or needing other mods, then you might want to check out the Black Magic line of LS camshafts. Like the LL-series cams, these are derived from the lobe design utilized in the Voodoo series of cams. Again, with a really fast opening ramp and a softer closing ramp, the Black Magic can deliver better valvetrain stability.

LS cam

Curious about which cam is right for your LS? The folks at Lunati have put together this easy-to-understand graph that should help.

“The Black Magic cams all require a spring swap as well as other mods,” Will affirms. “These camshafts are catered to the more hardcore street/strip and all-out race applications. Like our LL cams, these are also available in stages to help simplify the process of what the end-user needs.”

Again, the same lobe technology is used here, but with no lift limitations. This allows enthusiasts to achieve some really serious horsepower numbers. Looking at the chart above will really give you some insight into fitments.

Stage I is designed for mild 4.8- and 5.3-liter “junkyard” turbo builds using small turbochargers. It can be used with a basic LS6-style spring and will make great power with 15 psi or less boost. Advertised duration: 264/269 degrees, duration at .050-inch 212/218 degrees, and valve lift measures .552/.552-inch. The LSA/ICL covers 113/111 degrees.

Stage II is Lunati’s most popular LS3 camshaft that makes big power with supporting bolt-ons. It has an aggressive idle quality. Cars with an automatic will require a stall converter for good drivability. The advertised duration is 275/291 degrees while duration at .050-inch hangs on for 225/238 degrees. Valve lift is a stout .612/.585-inch, and the LSA is 113/110 degrees.

According to Lunati, you will definitely wake the neighbors with the Stage III camshaft. This is well suited for use in a lightweight car with a two-speed automatic. In a 5.3- or 6.0-liter engine where you are pushing hard or utilizing a large turbocharger(s) with minimal backpressure, this cam is a great choice. The advertised duration comes in at 285/290 degrees and duration at .050-inch is 230/235 degrees. Valve lift is a hefty .609/.610-inch, and the LSA/ICL is 115/110 degrees.

The Stage IV is perfect for a max effort 5.3, 6.0-liter, or larger engine spinning to 7,000 rpm. Advertised duration is 289/294 degrees and duration at .050-inch rolls in at 234/239 degrees. Valve lift: .612/.610-inch, and LSA/ICL is 114/109.

It’s never been easier to make more horsepower with an OE application. Whether you’re just getting into the LS world and like the aspect of an easy cam swap or you’re a seasoned enthusiast who isn’t going to shy away from a more in-depth upgrade, the new Lunati camshafts will allow anyone to customize their engine and create the perfect combination in their hot rod.

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Randy Bolig

Randy Bolig has been working on cars and has been involved in the hobby ever since he bought his first car when he was only 14 years old. His passion for performance got him noticed by many locals, and he began helping them modify their vehicles.
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