Choosing the right camshaft for your Gen3 HEMI is one of the most important decisions you'll make when building your Challenger, Charger, Ram, or Jeep. A cam swap can transform your HEMI from a mild-mannered daily driver into a tire-shredding beast, but only if you select the right profile and support it properly.
After installing hundreds of camshafts in HEMI engines here at Raw Exotics, I've learned what works, what doesn't, and what you need to know before you drop thousands of dollars on a cam package. This guide covers everything from VVT vs non-VVT cams to supporting modifications and realistic power expectations.
Understanding VVT vs Non-VVT HEMI Camshafts
The first thing you need to understand is that Gen3 HEMIs come in two distinct flavors when it comes to camshafts: Variable Valve Timing (VVT) and non-VVT. Your engine's production year determines which type you have, and this completely changes your cam selection options.
Non-VVT HEMI Engines (2003-2008)
The earlier 5.7L HEMI engines from 2003-2008 use a traditional fixed-timing camshaft system. These engines are actually simpler to work with for cam swaps because there's no VVT system to worry about. The cam is a straightforward mechanical component that opens and closes the valves at fixed intervals based on crankshaft position.
For non-VVT engines, you have access to a massive selection of aftermarket camshafts ranging from mild street grinds to full race profiles. Popular options include:
- Comp Cams XE268H: Great street cam with excellent low-end torque and a lopey idle. Around 0.500" lift, 268° duration. Expect 40-60 horsepower gains.
- Texas Speed & Performance TSP Stage 2: Aggressive street/strip profile with 0.525" lift and strong mid-range power. 50-70 hp gains typical.
- Arrington Performance Thunder Series: HEMI-specific designs optimized for the Eagle heads. Multiple stages from mild to wild.
- Trick Flow Stage 3: Serious performance cam requiring ported heads and supporting mods. 0.550"+ lift, 70-90 hp potential.
VVT HEMI Engines (2009+)
In 2009, Chrysler introduced Variable Valve Timing to the HEMI platform. This system uses a cam phaser on the intake cam to advance or retard valve timing based on driving conditions, improving both low-RPM torque and high-RPM power while also enhancing fuel economy and emissions.
The VVT system adds complexity to cam selection. You essentially have three options:
- Keep VVT Active: Use a VVT-compatible aftermarket cam. These cams work with the factory phaser system and maintain variable timing. Companies like Comp Cams and Texas Speed offer VVT cams, but selection is limited compared to non-VVT options.
- Delete VVT: Install a non-VVT cam and use a cam phaser delete kit. This gives you access to the entire catalog of non-VVT cams but requires additional parts and tuning to disable the VVT system in the ECU.
- Aftermarket VVT Controller: Some builders use aftermarket VVT controllers to run aggressive cams with custom VVT maps, but this is complex and expensive.
At Raw Exotics, we typically recommend VVT delete for serious builds. While you lose the variable timing benefit, you gain access to proven cam profiles and eliminate a potential failure point. For mild street builds on newer trucks and SUVs, keeping VVT active makes sense for maintaining drivability and fuel economy.
Understanding Camshaft Specifications
When you're looking at cam specs, several numbers determine how the cam will perform. Let's break down what these specifications actually mean and how they affect your engine.
Duration
Duration is measured in degrees of crankshaft rotation and tells you how long the valve stays open. Duration is typically listed at two different lift points: advertised duration (measured from the first movement to the last) and duration at 0.050" lift (a more standardized measurement).
For HEMI engines, here's what different duration ranges typically provide:
- Stock HEMI: Around 190-200° at 0.050". Smooth idle, great drivability, stock power.
- Mild Street (210-225°): Slight lope at idle, improved mid-range power, maintains good low-end torque. Daily driver friendly.
- Aggressive Street (225-235°): Choppy idle, significant power gains through the mid and top end, some loss of low-RPM torque. Still streetable but more temperamental.
- Race (235°+): Very rough idle, poor low-end, massive top-end power. Not ideal for street use unless you have supporting mods and don't mind the compromises.
Lift
Lift refers to how far the valve opens, measured in inches. More lift generally means more airflow, which translates to more power. However, lift is limited by several factors including valve spring pressure, piston-to-valve clearance, and valve guide wear.
For Gen3 HEMIs with stock valve springs, you're typically limited to around 0.500" lift. Beyond that, you need upgraded valve springs to prevent valve float at high RPM. Most aggressive street cams run 0.520"-0.550" lift and absolutely require upgraded springs.
Lobe Separation Angle (LSA)
LSA is the angle between the peak lift points of the intake and exhaust lobes. This spec has a huge impact on how the engine behaves:
- Tight LSA (106-110°): More valve overlap, choppier idle, better cylinder scavenging, more top-end power. Can hurt idle vacuum and low-end torque.
- Wide LSA (112-116°): Less overlap, smoother idle, better low-end torque, better idle vacuum. Stock HEMIs typically run 114-116° LSA.
For street HEMIs, we typically recommend LSA in the 110-112° range. This provides a nice idle tone without destroying low-end drivability.
Supporting Modifications Required
Installing a camshaft isn't a standalone modification. To make power safely and reliably, you need supporting modifications. The level of support required depends on how aggressive your cam is.
Essential Supporting Mods (All Cam Swaps)
These modifications are required for any cam swap, regardless of how mild or aggressive:
- Valve Springs: Unless you're installing an extremely mild cam (under 0.480" lift), you need upgraded valve springs. Stock springs will cause valve float and potential valve-to-piston contact with aftermarket cams. Budget $300-600 for a quality spring kit.
- Pushrods: Hardened pushrods are recommended, especially with higher spring pressures. Stock pushrods can flex or fail with aggressive springs. Budget $200-400 for a set.
- Timing Chain: While the stock chain often survives, we recommend replacing it during a cam swap. Budget $150-300 for a quality double-roller timing set.
- Custom Tuning: This is non-negotiable. Your engine needs a custom calibration to adjust fueling, spark timing, and VVT parameters (or disable VVT if deleted). Expect $600-1200 for professional tuning.
Recommended Supporting Mods (Aggressive Cams)
For cams over 0.520" lift or 225° duration, these additional mods will help you maximize performance and reliability:
- Long Tube Headers: More aggressive cams need better exhaust flow. Headers significantly improve scavenging and power. Budget $1200-2000 installed.
- Cold Air Intake: More airflow in requires more airflow out. A proper intake system helps feed the engine. Budget $300-500.
- High-Flow Fuel Injectors: Bigger cams often need more fuel, especially on forced induction or E85. Budget $600-1200 for quality injectors.
- Higher Stall Torque Converter (Automatics): Aggressive cams shift the powerband higher in the RPM range. A 2800-3200 RPM stall converter helps get you into the powerband. Budget $800-1500.
- Ported Cylinder Heads: For maximum power, ported heads are essential with big cams. This is where you'll see the biggest gains. Budget $1500-3000 for professional port work, or $3000-5000 for fully built heads.
Power Expectations: Real-World Numbers
Let's talk realistic power gains. The internet is full of exaggerated claims, so here's what we actually see on the dyno here in Houston after hundreds of HEMI cam swaps.
Mild Street Cam (Stock Engine)
Cam swap only, with supporting mods (springs, pushrods, tune), on an otherwise stock 5.7L or 6.4L HEMI:
- 5.7L HEMI: Stock ~370 hp → 410-430 hp (40-60 hp gain)
- 6.4L HEMI: Stock ~485 hp → 530-560 hp (45-75 hp gain)
Aggressive Cam + Headers + Intake
More aggressive cam with full bolt-ons (headers, intake, tune):
- 5.7L HEMI: 450-480 hp (80-110 hp over stock)
- 6.4L HEMI: 580-620 hp (95-135 hp over stock)
Full Build (Cam + Ported Heads + Bolt-Ons)
Serious naturally aspirated build with aggressive cam, ported heads, and full supporting mods:
- 5.7L HEMI: 500-530 hp
- 6.4L HEMI: 650-700 hp
These are realistic, conservative numbers we've proven on our dyno. Your results may vary based on altitude, fuel quality, and specific build details.
Installation Considerations
HEMI cam installation is not a beginner DIY job. The engine requires significant disassembly, and there are several critical steps where mistakes can destroy your engine.
Labor Time and Cost
Expect 12-16 hours of labor for a complete cam swap including springs, pushrods, timing chain, and all supporting work. At professional shop rates, that's $1500-2400 in labor alone. Add another 4-6 hours ($400-800) for custom tuning.
Common Installation Mistakes
- Incorrect Valve Spring Installation: Springs must be installed with the correct shimming and seat pressure. Too much or too little pressure causes problems.
- Improper Cam Timing: The cam must be degreed and installed at the correct position. Off by even a few degrees and you'll lose power or risk valve-to-piston contact.
- Inadequate Break-In: Flat tappet cams (if used) require a specific break-in procedure with high-zinc oil. Skipping this causes premature cam lobe wear.
- Reusing Old Hardware: Bolts, gaskets, and seals should be replaced. Reusing old parts leads to leaks and failures.
Our Top HEMI Cam Recommendations
Based on hundreds of installs, here are our go-to camshaft recommendations for different applications:
Best Daily Driver Cam (5.7L)
Comp Cams XE262H or TSP Stage 1.5: Mild lope, great mid-range power, maintains good MPG and drivability. Perfect for a daily driven Charger or Ram that you want to have more personality.
Best Street/Strip Cam (5.7L)
Texas Speed Stage 2 or Comp XE274H: Noticeable idle, strong power gains throughout the RPM range, still streetable but more aggressive. Great for Challengers that see weekend track duty.
Best Daily Driver Cam (6.4L)
Arrington 392 Hellfire or TSP Stage 1: 392-specific profiles that work with the larger displacement. Improves on the already-strong factory cam without going overboard.
Best All-Out Power (6.4L)
Comp XR288 or Trick Flow Stage 3: Serious performance cam for built 392s with ported heads. Not for daily driving, but makes massive power on a fully built combination.
The Bottom Line: Is a Cam Swap Worth It?
A HEMI cam swap is absolutely worth it if you want to transform your car's character and add significant power. However, it's not cheap—plan on $3000-5000 all-in for parts, labor, and tuning for a basic cam package, or $6000-10,000+ for an aggressive build with supporting mods.
The cam needs to match your goals. A mild daily driver doesn't need a race cam, and a weekend warrior won't be happy with a stock-feeling profile. Work with an experienced shop (like us!) to select the right combination for your specific vehicle and usage.
"The biggest mistake I see is people buying the biggest cam they can find without considering drivability or supporting mods. A properly matched cam package will make your HEMI come alive without destroying the driving experience."
Ready to Cam Your HEMI?
If you're in the Houston area and ready to wake up your HEMI, we'd love to help you build the perfect cam package. We'll help you choose the right profile, handle all the installation work, and dial in a custom tune that maximizes power and reliability.
Give us a call at (713) 299-1168 or stop by the shop. We'll go over your goals, budget, and build plan to create a cam package that delivers exactly what you're looking for.