6.1 HEMI camshaft
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6.1 HEMI Cam Kit Upgrade Guide

Chandler Stark

Meet Chandler

Chandler is an automotive expert with over a decade of experience working on and modifying cars. A couple of his favorites were his heavily modded 2016 Subaru WRX and his current 2020 VW Golf GTI. He’s also a big fan of American Muscle and automotive history. Chandler’s passion and knowledge of the automotive industry help him deliver high-quality, insightful content to TuningPro readers.

From 2005–2010, the 6.1 HEMI V8 was the top of the class for Dodge performance. Dodge put it inside the likes of the Charger/Challenger SRT-8 and Chrysler 300C SRT-8, and even the Grand Cherokee and Magnum SRT-8s, too. Depending on the model and year, it produced 420-425 horsepower and 420 lb-ft of torque. For its time, it was one of the fastest cars on the road. Yet, with the newer 6.4 HEMIs producing more than 480 horsepower stock, the 6.1 can feel a little sluggish and underpowered. That’s why one of the top mods for increasing horsepower and torque is a 6.1 HEMI cam kit upgrade. With just a cam swap, you can easily add serious horsepower and torque and transform the engine’s power band.

Read on to find out the best 6.1 HEMI cam kit upgrades to give you the best performance. Make sure to check out our other content for your build, including our 6.1 HEMI engine guide, intake manifold upgrade guide, 6.1 HEMI supercharger guide, and common engine problems guide

6.1 HEMI Cam Kit Upgrade Basics

6.1 HEMI camshaft
6.1 HEMI camshaft from Comp Cams

First, let’s talk about 6.1 HEMI cams, what they do, how they work, and the potential reasons for upgrading them. The camshaft is part of the valve train, which is responsible for allowing air to move in and out of the engine. On an overhead valve engine, like the 6.1 HEMI, the camshaft is actually located inside the cylinder block.

The 6.1 HEMI cam is controlled by a timing chain, which makes it spin. The camshaft has several lobes or “cams” on it, and each lobe corresponds to a different valve. As the timing chain spins the camshaft, the lobes push up and down on lifters, which in turn actuate pushrods. The pushrods are connected to rocker arms, which sit in the cylinder head.

As the lifters and pushrods move up and down they actuate the rocker arms, which control the opening and closing of the valves. Valve springs surround the valves, keeping them closed until the rocker arm pushes them down. The 6.1 HEMI has 16 valves, one intake and one exhaust for each cylinder, and one camshaft. The single camshaft is responsible for controlling all 16 valves, and the 6.1 does not use variable valve timing or multiple displacement systems. 

Upgrading to a performance camshaft is a great way to increase both horsepower and torque, and it can also shift the power band to the left or right, too. The purpose of upgrading the camshaft is to increase how much the valves open and how long they stay open. By opening the valves more and keeping them open for longer, the engine can breathe in a substantial amount more air. More air means more power, sometimes as much as 50+ horsepower on the 6.1 HEMI.

Camshaft Duration, Lift, and Lobe Separation Angle

When looking at 6.1 HEMI cam kits, you’ll see a lot of different numbers thrown at you. The most common specs are valve duration, valve lift, and lobe separation angle. Here’s what all of those mean and how they affect performance. 

First up is valve duration. Valve duration is measured in degrees and is based on the rotation of the crankshaft, which controls the camshaft. A higher valve duration means that the valve is open for longer, thus it is able to let more air in/out. The 6.1 HEMI stock camshaft has durations of 221°/225°, with the first number covering the intake valve and the second the exhaust valve. Usually, duration values are measured at 0.050” lift, which is considered the industry standard.

Speaking of lift, that’s the next measurement you will typically see for a camshaft. Lift is measured in terms of inches, and tells how much the valve actually opens. Higher lift means the valve is open wider, allowing for more air to enter/exit the engine. Stock HEMI valve lift is 0.571”/0.551”, which is pretty exceptional.

Finally, there is the lobe separation angle (LSA). The LSA determines the specific angle between the intake and the exhaust lobes on the camshaft. A greater LSA means the lobes are further apart, and a smaller LSA means they are tighter. Typically, with a wider LSA you will give you more top-end and mid-range power at the expense of low-end torque. A narrower LSA will instead give you higher torque, but usually also greater cylinder pressures and worse idle. 

Stock Camshaft Specifications

For a stock camshaft, the 6.1 HEMI uses a pretty aggressive stick. The stock cam duration is 221°/225°, and the lift is 0.571”/0.551”. That is both more duration and higher lift than you would typically see from a stock camshaft, but again this was powering the SRT-8s.

This has both good and bad implications for a 6.1 HEMI cam kit upgrade. On the one hand, 6.1 HEMI cam upgrades are still very popular and will net some good performance gains. However, due to the construction engine, you can only upgrade the camshaft so much. 

Limitations will prevent you from putting on too big of a camshaft with too much lift and duration, without making several other costly internal upgrades or retarding the camshaft, which hurts performance. Still, you can get some decent gains on the stock cylinder heads, though you may need to upgrade valve springs. 

Dodge 6.1 HEMI Cam Kit Supporting Mods

Speaking up valve springs, those are a recommended supporting mod for upgrading the camshaft on the 6.1 HEMI. Luckily, the 6.1 HEMI does not have Chrysler’s multiple displacement system (MDS), which affects the valve train. However, it also does not have variable valve timing, which would have benefited performance and fuel economy. 

Still, with most 6.1 HEMI cam kits, you do not need to make any valve train upgrades. Most camshafts can reuse the stock springs and pushrods without issue. However, camshafts with significantly higher durations and lifts will require both upgraded valve springs and pushrods. Without upgrading the springs and pushrods, the new camshaft could potentially stress them too much, causing them to fail and potentially do lots of damage. 

In addition to the mechanical upgrades, you will also need to have some form of ECU tuning for your 6.1 HEMI if you plan on getting a lumpier camshaft. The stock ECU programming is only meant to work with the stock camshaft, springs, and pushrods. Sticking in brand new parts with completely different specs then OEM will not work with the stock programming. It can cause serious issues if the car is not also tuned, so keep that in mind before making any cam upgrades. 

6.1 HEMI Cam Kit Upgrade Benefits

The top 6.1 HEMI cam upgrade benefits are:

  • Increased horsepower and torque
  • Improved top-end power
  • Improved low-end torque
  • Larger power-band

There are several different benefits to a 6.1 HEMI cam kit upgrade. However, there is also some give and take and tradeoffs that need to be considered, too. The biggest benefit to a 6.1 HEMI cam upgrade is the increase in horsepower and torque. With a higher duration and/or larger lift camshaft, the engine will take in a lot more air, which produces more power. 

Importantly, the type of camshaft you choose will change where that power comes on, and whether you gain more torque or horsepower. Typically, a camshaft with more lift and more duration will net more gains on the top-end, shifting the curves to the right for both horsepower and torque. The less duration and you will see the power-band shift to the left with more low-end torque. 

LSA is also important in combination with duration and lift. For the 6.1 HEMI, a camshaft that has a wider LSA will have a wider power-band with more torque past 3,000 RPM. A narrower LSA will usually have better torque down-low, but it probably won’t last for as long. It’s important to consider all of these factors with a 6.1 HEMI cam kit to make sure you are getting the right cam for your build and use. 

Top Dodge 6.1 HEMI Cam Upgrades

6.1 HEMI camshaft
Arrington High Performance Camshaft

These are the top 6.1 HEMI camshaft upgrades:

  • Arrington SR-2B and ST-3A
  • Comp Cams XFI-273 & HRT-273
  • SRT Max Plus

1) Arrington Camshaft Upgrades

First on our list of best Dodge 6.1 HEMI cam kit upgrades is from Arrington Performance. Arrington has two different cams that both perform very well. These are the Arrington SR-2B cam and the Arrington ST-3A cam. Both of these provide significant gains over stock, with the ST-3A being a bit more aggressive. They both require upgraded valve springs and pushrods. 

According to the manufacturer, the SR-2B cam will provide around 40 horsepower and 20 lb-ft of torque in gains. This is from a duration of 223°/234° with lift of .560”/.555”. In contrast, the lumper ST-3A has 225°/234° duration with lift of .592”/.594”. As you can tell, the ST-3A has more intake duration and much more intake/exhaust valve lift than the SR-2B. This translates to larger gains of 50 horsepower and 20 lb-ft of torque. 

2) Comp Cams Camshaft Upgrades

Next up we have two recommendations from Comp Cams. As most people probably know, Comp Cams is one of the top manufacturers in the industry, and they are huge within the HEMI and larger Dodge community. Comp Cams have several different families of camshafts, and we suggest one each from the HRT and XFI families. 

For the HRT, we suggest the Stage 2 HRT 220/230 camshaft. According to the manufacturer, it provides the best average torque and power of any sub .600” lift Gen III Hemi camshaft they have tested. It has a little less duration than both of the Arrington cams, and similar lift as the ST-3A. The Stage 2 HRT will require upgraded valve springs. 

For the XFI, we suggest the XFI 273H-14 camshaft. The XFI gives an incredibly strong midrange, with its strongest power coming over 2,500 RPM. It does require upgraded valve springs and pushrods. It has a little less lift than the Arrington cams and the HRT, but slightly better duration specs than the HRT. Overall, both Comp Cams upgrades are solid and will provide good gains.

3) SRT Max Plus Camshaft Upgrade

For our final 6.1 HEMI cam upgrade, we recommend the Inertia SRT Max Plus camshaft. This has been the most popular 6.1 HEMI cam on the market for more than a decade, and it was made in conjunction with Crower Racing. While Crower does not give specifications for this camshaft, they consider it to be the biggest possible cam you can run with the stock pistons in place with having to negatively retard the camshaft, which hurts low-end and mid-range power.

It’s their most popular camshaft choice, by far, and it uses the stock valve springs and pushrods. While it’s unfortunate they do not list specs, it’s easily one of the top cam choices on the market, and has been used in probably thousands of 6.1 HEMIs by this point.

Dodge 6.1 HEMI Cam Kit FAQ

How much horsepower does a camshaft add to a 6.1 HEMI?

Depending on the camshaft, you can easily add more than 50 horsepower and 20 lb-ft of torque to the 6.1 HEMI. There are many different camshaft grinds available, with some that emphasize mid-range power and others that are great for top-end results.

Is a 6.1 HEMI camshaft upgrade a good idea?

A 6.1 HEMI camshaft upgrade is a great way to increase horsepower and torque without completely breaking the bank. You can seriously change the power-band and make the car much more powerful with the right 6.1 HEMI cam kit.

Which is the best 6.1 HEMI cam kit?

Many people will say the Arrington Performance SR-2B and ST-3A 6.1 HEMI camshaft upgrades are the best. They add more than 40 horsepower and 20 lb-ft of torque, and are very highly reviewed.

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