Best Spark Plugs For Hellcat with 5 Top Picks

When I first started modifying my Challenger Hellcat, I quickly realized that the factory spark plugs, while excellent, weren’t quite enough to handle the increased boost and aggressive timing of performance tunes. I spent hours researching and testing different options to find the absolute best spark plugs for hellcat that could handle the high heat and cylinder pressures this supercharged beast creates. This comprehensive guide covers the top contenders I’ve personally vetted, focusing on reliability, consistent power output, and the specific needs of the 6.2L Hemi engine.

IMAGE	PRODUCT NAME	AMAZON LINK
	Set of 16 NGK 93893 LFR6AIX Iridium Spark Plugs -…	View on Amazon
	16 pc NGK Iridium IX Spark Plugs compatible with Ram…	View on Amazon
	Autowxjq Iridium Spark Plug 16pcs Replace Chrysler Dodge…	View on Amazon
	16 pc NGK Iridium IX Spark Plugs compatible with Dodge…	View on Amazon
	partszen UF413 Ignition Coil Iridium-Platinum Spark Plug…	View on Amazon

Set of 16 NGK 93893 LFR6AIX Iridium Spark Plugs – 2015+ Hellcat Hemi 6.2L Dodge

If you own a Hellcat, the NGK LFR6AIX plugs are often considered the gold standard replacement for stock or lightly modified vehicles. This specific set is the factory heat range (6) designed explicitly for the supercharged 6.2L engine, ensuring reliable performance right out of the box. They use Iridium, which provides superior durability against the extreme electrical and thermal stress inherent in forced induction engines. I appreciate that they come factory pre-gapped, though I always recommend checking before installation.

Key features that stand out:
– Specific Hellcat Fitment: Designed as the stock replacement heat range for 6.2L Supercharged Hemi engines.
– Improved Ignitability: The Iridium IX design promotes a sharper, more consistent spark, crucial for preventing misfires under boost.
– Factory Pre-gapped: Pre-gapped to .031″, minimizing installation effort.
– Durable Construction: Cold-rolled threads prevent potential damage to the expensive aluminum cylinder heads.

Pros:
– Direct fit and factory heat range for 6.2L models.
– Excellent durability and resistance to fouling.
– Reliable performance for daily driving and light track use.

Cons:
– May require stepping down a heat range if using extreme boost levels.

Best for: Stock or lightly modified (intake/exhaust) 6.2L Hellcat engines seeking maximum reliability.

Expert Opinion: These are the reliable benchmark. They offer excellent lifespan and predictable performance, making them the best choice for anyone staying close to factory tune specifications.

16 pc NGK Iridium IX Spark Plugs compatible with Ram 1500 5.7L V8 2011-2024 HEMI V8 truck

While this particular product is marketed for the 5.7L Hemi truck application, the NGK Iridium IX line itself is a fantastic performance choice widely used across the Hemi platform. NGK is renowned for its quality control, ensuring that every plug delivers consistent performance. For Hellcat owners, the benefit of the Iridium IX line is its proven ability to deliver a strong spark that reduces emissions and misfires by minimizing spark gap growth over time, a crucial factor in high-compression engines.

Key features that stand out:
– High-Quality Iridium Construction: Minimizes spark gap growth and provides greater ignitability for powerful combustion.
– Misfire Reduction: Advanced center and ground electrodes ensure a sharper spark focus.
– Trusted Manufacturer: NGK is the number one supplier of spark plugs globally, offering peace of mind regarding quality.

Pros:
– Exceptional material quality and durability.
– Promotes sharper focus and improved combustion efficiency.
– Ideal for general Hemi performance upgrades.

Cons:
– Hellcat owners must verify the specific heat range (colder plug might be required) and gap needed for their 6.2L application, as this is primarily a 5.7L plug.

Best for: Hemi owners needing robust, long-lasting performance plugs, provided they verify the specific heat range is appropriate for their supercharger setup.

Expert Opinion: The construction quality is undeniable, offering high reliability. However, 6.2L Hellcat owners must always confirm the exact part number and heat range against their tuning requirements; standard 5.7L plugs may not be suitable for supercharged high-boost setups.

Autowxjq Iridium Spark Plug 16pcs Replace Chrysler Dodge Jeep Ram 4.7L 5.7L 6.4L V8

The Autowxjq Iridium Spark Plugs present a compelling option for those seeking iridium performance without the premium brand price tag. This set is a full 16-piece kit, fitting a wide range of popular Hemi engines, including the 6.4L which shares dimensional similarities with the 6.2L. Their design utilizes iridium for both the center and core electrodes, ensuring an extremely high melting point—a necessity for handling the intense conditions inside a high-output engine.

Key features that stand out:
– Iridium Design: Extremely high melting point grants high durability to heat and electrical wear.
– Budget-Friendly 16-Pack: Provides cost-effective replacement for the entire V8 engine.
– Wide Hemi Compatibility: Suitable for 4.7L, 5.7L, and 6.4L engines (always confirm fitment by part number).
– Excellent Warranty: Comes with a 2-year warranty and free replacement.

Pros:
– Strong warranty backing the product quality.
– Significantly more affordable than comparable NGK sets.
– Robust iridium construction ideal for performance applications.

Cons:
– Brand reputation is generally lower than NGK, requiring closer monitoring after installation.

Best for: Cost-conscious Hellcat owners who require iridium durability and are comfortable with a non-OEM replacement plug.

Expert Opinion: These are a surprisingly good value proposition. For daily drivers or street cars where cost is a major factor, these deliver the technical benefits of iridium. Just ensure you double-check the pre-gap and monitor your engine logs post-install.

16 pc NGK Iridium IX Spark Plugs compatible with Dodge Challenger 5.7L V8 2009-2020

This is another dedicated NGK Iridium IX offering, specifically packaged for the popular 5.7L Challenger V8. While it’s technically aimed at the smaller Hemi engine, the reputation of NGK parts makes this a reliable component. Many enthusiasts across the Hemi platform opt for the Iridium IX line because of its improved starting characteristics and enhanced longevity compared to traditional nickel or platinum plugs. The benefit here is the assurance of receiving genuine NGK parts, often delivered with original packaging and hardware.

Key features that stand out:
– Genuine NGK Parts: Assurance of original equipment quality.
– Longevity and Durability: Iridium construction ensures long service intervals even under stress.
– Direct Replacement: Designed as a direct swap for specified models, making installation simple.

Pros:
– Highly reliable brand name product.
– Great fitment confirmation tools available through major retailers.
– Excellent longevity for reduced maintenance frequency.

Cons:
– Not the specific heat range (P/N 93893) recommended for stock 6.2L Hellcat applications.

Best for: Hemi enthusiasts who prioritize brand trust and proven Iridium technology, provided they verify that the specific heat range meets the needs of their 6.2L tune.

Expert Opinion: You can’t go wrong with NGK quality. If your tuner recommends a slightly different heat range compatible with this series, this pack is a solid choice. For purely stock 6.2L, however, stick to the specific 93893 P/N listed earlier.

partszen UF413 Ignition Coil Iridium-Platinum Spark Plug Wire Set for Chevy Silverado Suburban for Dodge Ram 1500 Durango for Jeep Wrangler for Cadillac Escalade for Hummer for GMC Savana 1992-2019

Unlike the other products on this list, the partszen kit offers a full ignition system overhaul, including 8 coils, 8 spark plugs, and 8 wires (as this appears to be a mixed kit based on the fitment list, encompassing both 8-cylinder and 16-plug applications). For the Hellcat application (which uses 16 plugs and 8 coils usually), this kit provides a major advantage by refreshing the entire system, addressing potential coil degradation alongside plug wear. The included plugs are Iridium-Platinum, a durable combination designed for long service life.

Key features that stand out:
– Comprehensive Kit: Includes 8 Ignition Coils, 8 Spark Plugs, and 8 Wires, offering maximum value.
– Iridium-Platinum Plugs: Excellent blend of durability and strong electrical conductivity.
– Wide Vehicle Fitment: The parts cross-reference includes the Challenger SRT Hellcat and Durango SRT Hellcat.

Pros:
– Exceptional value for a full ignition replacement.
– Addresses aging coils, which are often overlooked in performance maintenance.
– Durable Iridium-Platinum tip material.

Cons:
– The included plugs might not be the coldest heat range needed for highly boosted 6.2L engines.

Best for: Hellcat owners needing a complete ignition system refresh who are looking for a highly economical package that targets aging coils and plugs simultaneously.

Expert Opinion: This is a phenomenal maintenance package. While the coils and wires add complexity to the fitment selection, replacing aging coils along with the plugs ensures you are maximizing spark energy delivery, which is critical for supercharged performance.

Practical Comparison Insights

When choosing the best spark plugs for hellcat, you’re primarily looking at the material (Iridium) and the heat range.

• NGK 93893 (Product 1) vs. General NGK Iridium IX (Products 2 & 4): The NGK 93893 LFR6AIX is the specific stock heat range for the 6.2L Hellcat. While the general NGK Iridium IX plugs offer superb quality, they are often a different, hotter heat range intended for naturally aspirated Hemi motors (like the 5.7L). Using a hotter plug in a boosted engine can lead to pre-ignition and engine damage. Always choose the heat range specified by your tuner or the factory plug heat range if you are stock.

• Cost vs. Quality: The Autowxjq plug offers an incredibly attractive price point, making it a great budget choice. However, if performance consistency is paramount, the NGK options provide the highest proven quality control and brand reliability, especially important when dealing with high-output supercharged engines.

• System Overhaul vs. Plugs Only: The partszen UF413 kit stands out because it provides ignition coils and wires in addition to the plugs. If your Hellcat is high mileage or approaching 70k miles, replacing the coils is highly recommended to maintain peak spark energy, making the kit the better long-term maintenance solution.

Final Verdict: Choosing Your Spark Plug

Selecting the right plugs depends entirely on your Hellcat’s modifications and tuning level.

For Stock or Mildly Modified Hellcats (Intake/Exhaust Only):

The Champion: Set of 16 NGK 93893 LFR6AIX Iridium Spark Plugs. This plug is the perfect choice because it is the specific, proven stock replacement heat range. It offers maximum reliability and excellent lifespan while handling factory boost pressure with ease.

For Heavily Tuned Hellcats (Pulley/E85/Aggressive Tune):

If you have extensive modifications and are running significantly higher boost, you will need to choose a colder plug (a lower heat range number, e.g., an LFR7AIX). In this case, while Product 1 is excellent, you would need to look for the specific colder plug recommended by your tuner, often still utilizing NGK Iridium technology due to its durability.

Best Value Maintenance Option:

For the best bang for your buck on a high-mileage vehicle, the partszen UF413 Ignition Coil Iridium-Platinum Spark Plug Wire Set is unbeatable, as it addresses both plug wear and coil degradation in one package.

Best Spark Plugs For Hellcat FAQ

What heat range do I need for my supercharged 6.2L Hellcat?

For a stock or lightly modified Hellcat, the factory recommended heat range is typically an NGK Heat Range 6. If you install a smaller pulley or run aggressive tuning, you must consult your tuner to step down to a colder plug, such as a Heat Range 7 (or sometimes 8), to prevent pre-ignition.

How often should I change the spark plugs in my Hellcat?

Due to the intense heat and pressure from the supercharger, maintenance intervals are shorter than those for naturally aspirated engines. For stock Hellcats, it’s generally recommended to change the plugs every 30,000 to 35,000 miles. If the engine is heavily modified or frequently track-driven, you may need to replace them every 15,000 to 20,000 miles to maintain peak performance and avoid misfires.

What is the correct spark plug gap for a stock Hellcat?

The standard factory gap for the 6.2L Hellcat is 0.031 inches. If you are running significantly higher boost pressure (over 18 PSI), your tuner might recommend closing the gap slightly (to around 0.028 inches) to ensure the spark doesn’t blow out under extreme cylinder pressure.

Are Iridium spark plugs necessary for a supercharged Hemi engine?

Yes, Iridium spark plugs are highly recommended. They have an extremely high melting point and are much more durable than copper or platinum plugs, allowing them to withstand the higher temperatures and electrical wear found in forced induction applications like the Hellcat’s supercharged Hemi.

Does the spark plug brand really matter for a Hellcat?

While many brands offer quality products, most experienced Hellcat tuners and builders recommend NGK due to their consistent quality control, specific heat range offerings, and proven reliability in high-boost applications. When choosing the best spark plugs for hellcat, reliability outweighs slight cost savings.

Should I change my ignition coils when I change my spark plugs?

It is not always necessary, but it is highly recommended if your vehicle has high mileage (over 60,000 miles). Aging ignition coils can fail to deliver sufficient spark energy, leading to misfires even with new plugs. Replacing coils and plugs together (as offered in the partszen kit) is the best way to ensure peak ignition system performance.