Best Spark Plugs For 3800 Supercharged Reviewed 2025

If you own a legendary Series II (L67) or Series III (L32) 3800 Supercharged engine, you know getting the ignition system right is absolutely critical. I’ve spent years tinkering with these boosted V6 platforms, and selecting the best spark plugs for 3800 Supercharged isn’t just about brand; it’s about finding the right heat range and precise gap to handle boost and prevent the dreaded pre-ignition or detonation. We’re going to walk through 10 top-rated options, detailing which plugs handle stock setups best, and which ones are tough enough for modified applications seeking maximum performance from the reliable 3800 supercharged engine.

IMAGE	PRODUCT NAME	AMAZON LINK
	ACDelco GM Original Equipment 41-101 Iridium Spark Plug	View on Amazon
	ACDelco Professional CR43TS Conventional Spark Plug (Pack…	View on Amazon
	NGK # 3186 G-Power Platinum Spark Plugs TR5GP – 8…	View on Amazon
	NGK 6619 Iridium Spark Plugs LFR6AIX-11-6 PCSNEW	View on Amazon
	NGK LKAR7BIX-11S Iridium IX Spark Plug (93501 Iridium Ix),…	View on Amazon
	Autolite APP3923 Double Platinum Automotive Replacement…	View on Amazon
	Autolite Iridium XP Automotive Replacement Spark Plugs,…	View on Amazon
	Autolite Iridium XP Automotive Replacement Spark Plugs,…	View on Amazon
	Iridium Spark Plugs 8 Pack 4469 LFR5AIX11 Fit for 5.7…	View on Amazon
	NGK # 6418 Iridium Spark Plugs BKR6EIX – 4 PCS…	View on Amazon

ACDelco GM Original Equipment 41-101 Iridium Spark Plug

This ACDelco plug is the gold standard for those seeking factory reliability and lifespan, making it an excellent choice for stock or mildly modified 3800 supercharged engines. The fine-wire Iridium tip ensures a very stable spark, which is crucial for smooth idling and efficient combustion under light boost. Owners appreciate that these plugs often require virtually no re-gapping straight out of the box, offering true peace of mind and excellent long-term durability.

Key features that stand out:
– Iridium offers excellent engine idle stability and smooth performance.
– Iridium fine-wire electrode helps burn away carbon deposits on the tip of the plug as they form.
– One piece suppressor seal helps block radio frequencies that can affect vehicle electronics.

Pros:
– Excellent OEM reliability and fitment.
– Extremely long service life due to Iridium construction.
– Reliable cold starting and quick acceleration.

Cons:
– Might not be cold enough for engines running high boost/smaller pulleys.

Best for: Stock L32/L67 engines prioritizing longevity and factory performance.

Expert Opinion: This is the baseline for the 3800 Supercharged. If you are staying at or near stock boost levels, this plug provides the best maintenance-free experience available.

ACDelco Professional CR43TS Conventional Spark Plug (Pack of 1)

For those looking for high conductivity and a traditional, easy-to-read plug, the ACDelco Professional CR43TS copper plug is a classic choice. While copper plugs require more frequent replacement than iridium, their superior conductivity and ability to handle high heat peaks make them favored by racers and tuners who need consistent, powerful sparks and frequent inspection. The black onyx coating also helps protect against common engine bay corrosion.

Key features that stand out:
– Copper core provides great heat transfer and helps maximize plug durability.
– Ribbed suppressor seal extends resistance and helps prevent spark ‘flash over’ and misfires.
– Black Onyx coating helps reduce corrosion.

Pros:
– Superior conductivity and powerful spark delivery.
– Lower initial cost compared to precious metals.
– Excellent heat dissipation for high-performance use.

Cons:
– Needs replacement far more often (every 10k–15k miles) than iridium options.

Best for: Performance tuning, frequent plug inspection, and highly modified 3800 Supercharged setups.

Expert Opinion: If you are running race gas or a smaller pulley (3.4” or less) and are constantly checking your tune, copper plugs like the CR43TS are often the best choice for stability under extreme load, provided you accept the reduced lifespan.

NGK # 3186 G-Power Platinum Spark Plugs TR5GP – 8 PCSNEW

The NGK G-Power Platinum series offers a noticeable step up in performance and durability over standard copper plugs without the premium price tag of iridium. The platinum tip resists fouling and provides a consistent, wide heat range suitable for many mildly boosted applications. This pack of 8 gives you spares or allows you to service multiple vehicles.

Key features that stand out:
– Designed to operate over a much wider heat range than ordinary plugs.
– Resists carbon buildup and pre-ignition.
– Patented triple gasket sealing process eliminates the possibility of combustion gas leakage.

Pros:
– Improved durability and stability compared to copper.
– Excellent resistance to fouling.
– Reliable mid-range performance solution.

Cons:
– Platinum typically doesn’t offer the extreme longevity of Iridium plugs.

Best for: Drivers seeking a balance of cost-effectiveness, durability, and reliable performance.

Expert Opinion: Platinum plugs are a good middle ground for those with modest performance upgrades (e.g., intake and exhaust) who want longer life than copper but don’t want to spring for full iridium pricing.

NGK 6619 Iridium Spark Plugs LFR6AIX-11-6 PCSNEW

NGK Iridium plugs are favorites among performance enthusiasts, and the 6619 is built to handle robust conditions. These plugs are engineered to manage wide heat ranges effectively, resisting carbon buildup even during hard driving sessions. The robust triple gasket sealing process ensures that all combustion pressure stays exactly where it should be, maximizing cylinder efficiency, which is essential when running boost on the 3800 supercharged engine.

Key features that stand out:
– Iridium Spark Plugs designed for performance.
– Resists carbon buildup and pre-ignition.
– Patented triple gasket sealing process for zero gas leakage.

Pros:
– Superior ignition and throttle response.
– Highly resistant to heat and electrical wear.
– Durable design suited for boosted applications.

Cons:
– Ensure the specific heat range (LFR6AIX) is correct for your exact modification level.

Best for: Highly reliable, long-life plugs for moderately modified L67/L32 engines.

Expert Opinion: When stepping up the performance of your 3800, NGK Iridium is often recommended due to its reliability and proven ability to handle higher cylinder pressures without breakdown.

NGK LKAR7BIX-11S Iridium IX Spark Plug (93501 Iridium Ix), 4 Pack

Designed explicitly for the performance enthusiast, the NGK Iridium IX line delivers extreme ignitability and superior anti-fouling characteristics. The 0.6mm laser-welded fine Iridium tip ensures a consistently stable spark, which translates directly into sharper throttle response. The tapered ground electrode minimizes electrical quenching, making this a top-tier choice for engines demanding maximum energy transfer under pressure.

Key features that stand out:
– 0.6 millimeter laser welded fine Iridium tip ensures high durability and stable spark.
– Longer insulator nose prevents fouling.
– Trivalent Metal Plating provides superior anti-corrosion and anti-seizing properties.

Pros:
– Extreme ignitability improves throttle response.
– Highly durable alloy, perfect for high-performance engines.
– Excellent anti-seizing plating aids maintenance.

Cons:
– Premium pricing due to advanced materials and design.

Best for: Performance seekers running dedicated performance tunes and high boost requiring immediate, focused ignitability.

Expert Opinion: The Iridium IX series is what many enthusiasts turn to when they want performance nearly matching copper, combined with the longevity of iridium. Just remember to check your gap carefully for boosted applications.

Autolite APP3923 Double Platinum Automotive Replacement Spark Plugs (4 Pack)

Autolite’s Double Platinum design focuses on longevity and consistent performance by featuring platinum on both the center and ground electrodes. This design virtually eliminates gap erosion, meaning the plug maintains its precise firing distance much longer than single platinum or copper options. The full copper core electrode provides better performance across all weather conditions.

Key features that stand out:
– Platinum-to-platinum firing for superior durability.
– Necked-down center electrode fires quicker and cleaner with less voltage.
– Super conductive Yttrium enhanced ground electrode provides superior heat transfer.

Pros:
– Virtually no gap erosion for consistent performance.
– Lower voltage requirement for easier starts.
– Trusted OE replacement brand reliability.

Cons:
– Double Platinum is generally less responsive than Iridium when used in high-boost applications.

Best for: Drivers seeking long-term, low-maintenance reliability without the cost of Iridium.

Expert Opinion: The APP3923 is a fantastic plug for the daily driven 3800 Supercharged where reliability over 50,000+ miles is paramount, making it a great set-and-forget option for stock setups.

Autolite Iridium XP Automotive Replacement Spark Plugs, XP3923 (4 Pack)

The Iridium XP line from Autolite is built for maximum efficiency and durability, engineered to last up to 100,000 miles. The 0.6mm fine-wire iridium centerwire tip is laser welded, ensuring focused and consistent ignitability that directly translates to improved fuel efficiency. For the 3800 Supercharged owner, this plug offers optimal performance and better durability, even in DIS (Distributorless Ignition System) setups common to these engines.

Key features that stand out:
– Engineered to last for up to 100,000 miles.
– 0.6mm finewire iridium centerwire tip design for maximum fuel efficiency.
– Platinum protected ground wire for maximum efficiency in all ignition types.

Pros:
– Exceptional lifespan and durability.
– Focuses ignition for improved fuel economy.
– V-trimmed ground electrode improves ignitability.

Cons:
– Requires careful handling during installation due to the fine-wire tip fragility.

Best for: Efficiency-minded drivers who want extreme longevity and optimal ignitability in a daily driver.

Expert Opinion: This is Autolite’s top-tier offering for extended maintenance intervals. Its performance benefits are noticeable, especially in maintaining a consistent spark throughout its very long life.

Autolite Iridium XP Automotive Replacement Spark Plugs, XP5363 (4 Pack)

Functionally similar to the XP3923 but potentially tailored to a slightly different heat range or thread reach (depending on the specific 3800 iteration), the XP5363 maintains Autolite’s commitment to superior durability and fuel efficiency. It features the same 0.6mm fine-wire iridium tip and platinum-protected ground wire. This plug delivers better overall ignitability and optimal performance for various replacement needs within the 3800 family.

Key features that stand out:
– Extended change interval, engineered to last up to 100,000 miles.
– Laser welded technology for focused and consistent ignitability.
– Platinum protected ground wire ensures durability in high-energy ignition systems.

Pros:
– Extremely long-lasting and durable construction.
– Reliable ignition leading to less fuel consumption.
– Optimal performance for a wide range of operating conditions.

Cons:
– Less common fitment than the standard 3923, requiring double-checking application.

Best for: High-mileage applications requiring long service life and reliable efficiency.

Expert Opinion: Always confirm the exact heat range and reach required for your specific 3800 Supercharged build (L67/L32) before purchasing, as seemingly small number changes (like 3923 vs 5363) are critical in boosted engines.

Iridium Spark Plugs 8 Pack 4469 LFR5AIX11 Fit for 5.7 Ram 1500 2500 3500, Dodge Charger Challenger, Chrysler 300, Jeep Grand Cherokee, Nissan Armada Titan, Infiniti FX45 QX56 92145, LZFR5C11, 5018

Note: While the title lists applications like Ram and Charger, the LFR5AIX-11 reference is a common NGK heat range often cross-referenced by tuners.

This 8-pack is a generic Iridium replacement aimed at providing high-durability, premium materials at a competitive price point. The core benefit for the 3800 Supercharged owner is the iridium construction, offering six times the hardness of platinum. The 0.6mm fine-wire tip combined with laser welding maximizes fuel efficiency and handles the high heat and electrical wear of boosted performance engines effectively.

Key features that stand out:
– Iridium fine wire center electrode’s durability is six times harder than platinum.
– 0.6mm finewire iridium centerwire tip design ensures exceptional fuel efficiency.
– Iridium alloy has extremely high melting point, ideal for today’s high performance engines.

Pros:
– Cost-effective bulk purchase (8 pack).
– Excellent durability against heat and electrical stress.
– Reliable fine-wire tip technology.

Cons:
– Generic branding may lack the specific quality control of major manufacturers like NGK or ACDelco.

Best for: Budget-conscious tuners needing iridium durability who purchase in bulk.

Expert Opinion: When opting for a non-branded plug that references popular OEM numbers, be sure to verify the precise heat range and gap required for your supercharged application, as heat range inconsistency can be dangerous under boost.

NGK # 6418 Iridium Spark Plugs BKR6EIX – 4 PCS NEW

The NGK Iridium IX 6418 (BKR6EIX) is arguably one of the most famous performance plugs across various boosted platforms, and it’s a highly recommended colder plug option for modified 3800 supercharged engines. The colder heat range (indicated by the ‘6’ in the BKR6EIX) helps prevent pre-ignition and detonation when running smaller supercharger pulleys and aggressive timing. This direct replacement part offers the proven reliability and ignitability of the Iridium IX line.

Key features that stand out:
– Genuine NGK Iridium IX 6418 Spark Plug.
– Direct replacement auto parts.
– Proven performance and reliability in high-boost scenarios.

Pros:
– Colder heat range is ideal for higher boost levels.
– Exceptional durability and anti-fouling characteristics.
– Reliable, genuine NGK quality.

Cons:
– Too cold for entirely stock engines, potentially leading to fouling during excessive idling.

Best for: Modified 3800 Supercharged engines running reduced pulley sizes and aggressive tuning (typically the go-to cold plug).

Expert Opinion: If you have performed significant modifications to increase boost on your 3800, you absolutely must switch to a colder plug, and the BKR6EIX is consistently one of the best choices for safely managing that extra heat.

Comparison and Short Insights

Choosing the right plug for your L67/L32 isn’t about finding the “best” plug overall, but the best plug for your specific modifications.

For stock or lightly modified 3800 Supercharged engines, the ACDelco GM 41-101 Iridium or the Autolite XP3923 Iridium plugs are fantastic for maximum lifespan (50,000+ miles). They maintain the OE heat range required for smooth street driving and reliability.

However, once you start reducing the pulley size (increasing boost), heat management becomes critical. This is where you must switch to a colder plug to avoid detonation. The NGK BKR6EIX (6418) is the gold standard for modified 3800s, offering a superior cold range and excellent iridium durability.

If you are a hardcore tuner or racer, you might consider the classic ACDelco Professional CR43TS Copper. Copper has the best conductivity and handles extreme heat bursts perfectly, though you’ll need to check and change them frequently—often every 10,000 miles or less.

Double Platinum plugs like the Autolite APP3923 offer a great compromise between the longevity of iridium and the cost-effectiveness of traditional plugs, ideal for daily drivers who want extended change intervals.

Remember that proper gapping is absolutely vital for supercharged applications. While stock gaps usually run around 0.060″, boosted engines typically require a tighter gap, often down to 0.050″ or even 0.045″ depending on your power level and coil pack strength.

Final Verdict: Choosing Your Spark Plug Strategy

The choice of spark plug for your 3800 Supercharged engine should align directly with your driving style and level of modification. Don’t simply pick the most expensive plug; choose the material and heat range that matches your boost level.

If you prioritize ultimate reliability and maintenance-free use on a stock L67/L32, your clear winner is the ACDelco GM Original Equipment 41-101 Iridium Spark Plug.

If your engine is modified with a smaller pulley (3.5″ or less) and performance tuning is a priority, you must select a colder plug. The NGK # 6418 Iridium Spark Plugs BKR6EIX is the proven, performance-ready solution favored by the 3800 community for safely handling increased cylinder temperatures.

If budget and a balance of performance/durability are key, the NGK # 3186 G-Power Platinum line offers a robust upgrade from copper without breaking the bank.

Ultimately, your best spark plugs for 3800 Supercharged are the ones properly gapped and correctly heat-ranged for the boost level you are running.

Best Spark Plugs For 3800 Supercharged: FAQ

Q1: What is the most critical factor when selecting a spark plug for a 3800 Supercharged (L67/L32) engine?

A: The most critical factor is the heat range. Boosted engines generate significantly more cylinder heat than naturally aspirated ones. If you install a stock (hotter) spark plug in a modified, high-boost L67, you risk pre-ignition and catastrophic detonation. You must step down to a colder plug, such as the NGK BKR6EIX, when running smaller pulleys.

Q2: Should I use copper, platinum, or iridium spark plugs in my boosted 3800?

A: Iridium plugs (like ACDelco 41-101 or NGK Iridium IX) offer the best combination of durability and lifespan (up to 100k miles), making them ideal for daily drivers. Copper plugs (like ACDelco CR43TS) offer superior conductivity and a powerful spark, which is preferred by tuners and racers who change them frequently for optimal performance. Platinum offers a middle ground for longevity.

Q3: What should I gap my spark plugs to if I have a modified 3800 Supercharged engine?

A: Stock 3800 Supercharged engines typically run a large gap around 0.060″. However, once you increase boost (by lowering the pulley size), the higher cylinder pressures can blow out the spark. Most modified 3800 owners successfully run tighter gaps between 0.050″ and 0.045″. Always consult your tuner for the precise gap recommendation based on your specific boost level and coil strength.

Q4: How often should I perform preventative maintenance on my spark plugs?

A: This depends entirely on the plug material. Iridium plugs can last 50,000 to 100,000 miles. Double Platinum plugs generally last 30,000 to 50,000 miles. Copper plugs should be inspected and typically replaced every 10,000 to 15,000 miles for optimal performance, especially in supercharged applications.

Q5: Why do some spark plug listings show eight plugs when the 3800 Supercharged is a V6 engine?

A: Many aftermarket spark plug manufacturers package their common replacements in sets of 4 or 8 because they serve popular V8 applications (like 5.7L Hemi) and other engines requiring more cylinders. Since the 3800 is a V6, you will only need 6 plugs; buying an 8-pack may leave you with two spares.

Q6: Can I use the same spark plug model regardless of whether I have an L67 or L32 3800 Supercharged engine?

A: Generally, yes. The L67 (Series II) and L32 (Series III) engines share very similar combustion chamber and ignition system requirements. However, always verify the specific thread reach and heat range required, especially if cross-referencing between brands like ACDelco and NGK, to ensure the optimal performance for your specific supercharged setup.