5.7 HEMI Camshaft Upgrade Guide - Best 345 HEMI Cams (2024)

The 5.7 HEMI is a great engine that has plenty of potential in NA form. Its Hemi design allows for excellent airflow that really wakes up with a more aggressive camshaft. We briefly discussed cam upgrade kits in our 5 best 5.7L V8 mods guide. Now it’s time to dive in-depth into cam upgrades from top to bottom. In this article, we discuss 5.7 HEMI camshaft upgrades including benefits, cost, lifters, springs, and plenty more.

5.7 HEMI Camshaft Upgrade Guide - Best 345 HEMI Cams (1)

About 5.7 HEMI Camshaft Upgrades

Camshafts are much more complex than your typical bolt-on mods like headers, intakes, and exhaust systems. There are important topics like duration, valve lift, and lobe separation. With the 5.7 HEMI camshafts, there are also differences in MDS vs non-MDS cams as well as VVT.

In the next couple of sections, we will iron out all of the basics you should understand before buying a 5.7 HEMI camshaft kit. Afterwards, we’ll move on to the benefits of cam kits and list a few excellent options for the 5.7L V8.

*VVT cams and non-VVT are not interchangeable, so 2003-2008 and 2009+ have different fitment.

MDS vs Non-MDS HEMI Cams

Most 2006+ 345 HEMI engines use MDS (Multiple Displacement System) technology. Cars with a manual transmission as well as HD 2500 and 3500 trucks do not use MDS. There are certain differences with the cams, and you cannot swap an MDS cam into a non-MDS HEMI. You can, however, use non-MDS cams in 5.7L V8s with MDS given you do the following:

  • Custom tune to disable MDS
  • Use non-MDS lifters
  • MDS solenoid delete plugs (optional)

In fact, most aftermarket camshafts do require deleting the multi-displacement system. Texas Speed & Performance (TSP) offers a complete kit to delete MDS on the 5.7 HEMI. This includes the MDS delete plugs, non-MDS lifters, and all the gaskets, seals, and bolts that should be replaced. You’ll still need proper tuning to account for the change, but that’s necessary for cam upgrades anyway.

There are a couple of cam options that will keep MDS such as swapping to a 392 HEMI camshaft. A few aftermarket cam upgrades that work with MDS are available, too. However, it’s generally best to delete the system for the best performance and reliability.

Cam Upgrade Specs

It’s common to see cams referred to with a bunch of numbers that look very confusing. For example, the TSP Stage 3 NA cam shows as: 223/232 .582/.582 113+3. What the heck do all these numbers mean? It’s a very fair question, but worry not. Let’s look through all of the numbers and explain the meanings:

  • 223/232 = valve duration @ 0.050″ lift
  • .582/.582 = valve lift
  • 113+3 = lobe separation angle (LSA)

*Specs for the stock 5.7 Eagle VVT with an auto trans are 186/208 .499/.493 115.

Valve Duration

The first numbers represent valve duration for the intake and exhaust valves, respectively. Duration is measured at 0.050″ of valve lift, which is the industry standard. Anyway, this is the amount of time – measured in degrees of crank rotation – that the valve is open.

Ultimately, valve duration tells you how long the intake and exhaust valves are open. The longer the valves stay open the more air & fuel you can fill in the cylinder. This is especially important at high-rpm where valves are opening and closing very quickly. Generally, more duration is better for top-end power while less duration helps low-end torque.

Modest 5.7 HEMI camshaft upgrades usually go with a duration around 214/222. More aggressive cams will come in around 226/235. All else equal, higher duration will lead to bigger peak power gains at the cost of minimal torque gains down low (or potentially even losses in torque).

Valve Lift

Next up is valve lift. Lift is the distance the valve opens from its seat; the numbers are for the intake and exhaust respectively. The further the 5.7L V8 HEMI valves open the more air is flowing in and out of the cylinder.

Higher lift cams generally offer better power and torque throughout the entire powerband. As such, there isn’t a big tradeoff for hp or tq like there is with valve duration. However, there are several limiting factors in how much lift you should run.

For one, 5.7 HEMI high lift cams require valve spring upgrades. This is something we recommend on the HEMI regardless of lift, and we’ll circle back to this topic in a few moments. There is also other head work that may be needed and other issues with too much lift. Anything over 0.650″ of lift is usually only seen in the racing world.

It’s common to see intake and exhaust valve lift in the .580 to .600 range for many aftermarket cams. Some really high-lift options like the Comp Cams Stage 3 are as high as .632/.619.

Cam Lobe Separation Angle

Lobe Separation Angle (LSA for short) is where things become a little more complex. In the original example, there is an LSA of 113+3. Let’s ignore the +3 for a moment and just look at the 113. LSA is the number of degrees between the peak lift points of the intake and exhaust lobes. This not only effects the powerband but it also plays a big role in idle quality, vacuum, and cam rpm range.

+3 means the cam timing is advanced 3 degrees, which then ties into the intake centerline (ICL). It’s getting a little too technical here, so let’s cut if off there for now.

Anyway, higher LSA is ideal for a wider powerband and also helps top-end power. A lower 5.7 HEMI LSA offers better low-end torque but makes the powerband much narrower. Ultimately, LSA on 5.7L V8 cams usually falls in the 112-116 ballpark and that’s a good range to stick with. If you really want to stray too far away from that we recommend working with a knowledgeable shop or doing lots of additional research.

Other Cam Considerations

Unfortunately, the info for 5.7 HEMI camshaft upgrades doesn’t quite stop there. It’s a big reason why it’s important to work with a reputable HEMI shop or do lots of research before buying cam kits. This isn’t the upgrade you want to simply piece things together with minimal knowledge. Anyway, let’s jump into a few more 345 HEMI cam topics before recommending some of the best cams on the market.

Valve Spring Upgrades

Remember, when talking about valve lift we briefly touched on 5.7 HEMI valve spring upgrades. Higher lift increases the stress on the valve springs. As such, valve springs are a good item to address with high-lift cams – especially cams pushing above 0.550 lift. Most aftermarket cams will exceed that lift.

Valve spring upgrades should advertise a maximum recommended lift. Additionally, cam kits should include valve spring upgrades or the option to upgrade to appropriate springs. For example, the Comp Cams and Texas Speed kits both include proper valve springs for the cam profile.

Phaser Limiter or Lock Kits

One topic that hasn’t come up yet is piston-to-valve clearance. The 5.7 HEMI is an interference engine which means there is some overlap in the area the pistons and valves travel. That can create issues when changing the valve lift and duration. Without addressing this the pistons and valves can contact each other and cause serious damage.

The engine uses cam phasers which are able to adjust camshaft position on the fly. It helps improve fuel efficiency while also delivering a better powerband. All great stuff. However, the phasers have such a large range of movement that bigger, aggressive cams can cause the pistons and valves to collide.

Enter 345 HEMI phaser limiters and lock kits. A limiter – like this one from Comp Cams – will limit the cam phasing to 14 crank degrees (7 cam degrees) to achieve the necessary clearance. There are also lock kits that, as the name suggests, completely lock the cam phasers from making any movement. Limiter kits are generally the best option since some cam phaser movement does help maximize power.

*Only 2009+ VVT HEMI engines use cam phasers, so this isn’t a concern on older non-VVT engines.

Complete Camshaft Upgrade Kits

Last but not least are other parts you may consider replacing while doing the cam install. Many shops have multiple cam options. One option is simply buying a 5.7 HEMI camshaft without any other components. You’d then just need an MDS delete kit with the non-MDS lifters if you just want the basics with a modest cam. Again, more aggressive cams will require additional parts like valve springs and phaser limiter/lock kits.

However, we highly recommend doing things right and opting for a complete 5.7 HEMI camshaft kit – especially on older HEMI’s. The Comp Cams Master Cam Kit includes the cam, lifters, phaser limiter, pushrods, valve springs, spring seats, valve seals, and more. This is all great stuff to replace/upgrade while installing a cam.

It’s also a good idea to replace things like the head gaskets, valve cover gaskets, and any other simple and inexpensive parts. These items shouldn’t add any labor costs and ensure a reliable setup for the longer-term.

Full kits aren’t always necessary but cams are an expensive and complex upgrade in the first place. If you’re spending all the time and money it’s best to do things right. It may be OK to cut corners, save money, etc. on smaller upgrades. 5.7 HEMI cams aren’t that, though. If a shop is doing the install then cams can cost $2,500-4,000+ all in. It’s not something you want to do the wrong way and have to go back and do it all over again. Do it right the first time.

Benefits of 345 HEMI Cam Mods

  • 30-70+ horsepower
  • 10-30+ torque
  • Better powerband
  • Sounds

All the 5.7 HEMI camshaft upgrade benefits revolve around performance. Aggressive cams designed for top-end power can show gains of 70+ peak horsepower. However, too big a camshaft can result in less daily drivability due to worse low-end performance.

Fortunately, the right HEMI cams can offer great peak power gains while improving the entire power curve. It’s not unrealistic to pick up 30-50whp up top while also seeing gains on the low-end and mid-range. These cam options offer a great balance and wide powerband for street use and daily driving.

Cams also deliver some awesome sounds. It’s hard to not appreciate the sound of a cammed 5.7 HEMI. Cams are expensive so we wouldn’t recommend cams for sound alone, but it’s a nice added benefit on top of the performance gains.

Best Camshaft Kits

Phew. That was a lot of info to cover and it could even be several times longer if we got into all the nitty gritty technical details. Hopefully it paints the picture that a 5.7 HEMI camshaft upgrade is a serious mod that might not be for everyone. Fortunately, we’ve done all the research to compile a list of some of the best 5.7 HEMI cam kits and upgrades.

Please note – this is by no means an exhaustive list of the best 5.7L V8 cams. There are tons of options out there and certain cams may be better or worse depending on specific goals and needs. We’re simply focusing on a few popular cams that are highly tested & proven, deliver great quality & performance, and come from reputable brands in the HEMI cam market. Here are some of our favorite 5.7 HEMI Cams:

  • 5.7L V8 Comp Cams Stage 2 Master Cam Kit
  • Texas Speed 5.7 HEMI Camshaft Upgrade Package
  • 345 HEMI Greene Racing Cam Kits

An Upgraded Cam Might Be The Best Bang-For-Buck Mod For The 5.7L HEMI

The 5.7L HEMI is a stout performance engine that is capable of plentiful airflow thanks to the HEMI design. A more aggressive camshaft can really wake up the 5.7L V8 with impressive power and torque gains. However, cams are a complex and serious upgrade so ensure you understand the basics before moving forward (or work with a knowledgeable shop).

A few considerations before choosing a camshaft include:

  • MDS vs non-MDS (& delete kits)
  • Cam specs/profile
  • Valve spring upgrades
  • Phaser limiter/lock kits
  • Other parts to upgrade/replace

It may seem overwhelming at first, but 5.7 HEMI camshaft upgrades are easy to understand with some reading. Hopefully, the bulk of the article above was a good starting point to get you going on a cam upgrade.

Texas Speed and Comp Cams are by far the most popular 5.7 HEMI cam kits. They’re both high-quality, excellent kits with different stages to accommodate various goals and needs. The Comp Cams stage 2 or TSP stage 3 are great options for aggressive cams that retain low-end performance and deliver great peak gains. Any larger cams are typically best suited for racing applications where daily driving isn’t a big concern.

5.7 HEMI Camshaft Upgrade Guide - Best 345 HEMI Cams (2024)
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