Name: Racing Resistor Spark Plug: Enables Performance, Handles Intense Conditions
Brand: Autolite
SKU: AR25
Price: 4.79 USD
Rating: 5.0 (1 reviews)

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$4.79

The ground electrode is cut-back from the center electrode to provide a gap, and its concave face ensures a constant gap to the center electrode. This design opens the spark face for better ignitability of the flame kernel and retains less heat, transferring it to the shell faster to reduce the risk of pre-ignition. Dyno testing has shown proven power gains, making it ideal for all aftermarket cylinder heads used in various racing venues, including oval and road racing. The cut-back ground electrode evolved from the practice of grinding back the side electrode, and it features a tapered seat type for optimal performance.

Product Features:

Opens spark face for better ignitability of flame kernel
Retains less heat, transfers heat to shell faster – reduces risk of pre-ignition
Dyno testing has shown proven power gains
Cut-back ground electrode evolved from practice of grinding back the side electrode
Optimal Performance: Features a tapered seat type for optimal performance in various racing venues, including oval and road racing.
Durable Design: Engineered to handle intense conditions, making it suitable for all aftermarket cylinder heads used in competitive racing environments.

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$10.79

Increased performance with World’s smallest Iridium Center Eletrode (0.4mm).

Product Features:

World’s smallest Iridium Center Electrode (0.4mm) for improved spark for maximum combustion
Patented 360-degree laser welding assembly process
U-groove and taper cut ground electrode to maximize flame propagation.
Withstands temperatures greater than 4000░ Fahrenheit
Burnished nickel plating for high temperature endurance and superior corrosion resistance
Wide range of part numbers for thousands of applications, including classic and collector cars
Iridium Power
Superior Performance: Designed for maximum performance under extreme conditions, this spark plug delivers more horsepower, faster and easier starts, and fewer misfires under heavy loads.
Enhanced Fuel Efficiency: The advanced iridium technology of the DENSO Iridium Power spark plug contributes to better fuel efficiency, making it an economical choice for your vehicle.
Low Voltage Requirement: This spark plug requires 5,000 volts less to fire compared to conventional spark plugs, ensuring reliable ignition with lower energy consumption.

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$3.49

Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Guaranteed to deliver quick starts, good fuel economy and smooth acceleration, Autolite Copper Core spark plugs are designed to meet or exceed OES design requirements. Consider upgrading to Autolite Platinum, Double Platinum or Iridium XP plugs for improved engine performance. Copper core plugs are the industry standard.

Product Features:

Copper-glass seal bonds insulator, terminal post center electrode together; assures full required voltage at spark gap; gas-tight seal (100% leak proof)
Multi-rib insulator reduces danger of “flash-over”
One-piece terminal post adds strength
Resistor reduces radio frequency interference (RFI) and electrode erosion
Quick Starts: Autolite Copper Core spark plugs are engineered to ensure your engine starts quickly and efficiently.
Good Fuel Economy: Designed to optimize fuel consumption, these spark plugs help you achieve better mileage.
Smooth Acceleration: Experience smoother and more responsive acceleration with Autolite Copper Core spark plugs.
OES Design Compliance: These spark plugs meet or exceed Original Equipment Service (OES) design requirements, ensuring reliable performance.
Tapered Seat Type: Featuring a tapered seat type, these spark plugs provide a secure fit and optimal performance.

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$4.49

Motorcraft Spark Plugs are original equipment on Ford Motor Company vehicles, engineered to meet strict Ford engineering standards for optimal performance and reliability. These spark plugs are matched to specific engines to provide enhanced durability, eliminate misfires, reduce fuel consumption, and optimize emissions. They are resistant to oxidation and arc erosion, feature a multi-rib insulator to protect against misfire, and offer service intervals of up to 100,000 miles. Designed with high-quality materials, Motorcraft Spark Plugs ensure reliable performance for almost any application and are backed by Motorcraft’s Service Parts Warranty. They are an exact fit for Ford, Lincoln, and Mercury vehicles and help prevent false check engine lights, delivering the same performance and reliability as the original components installed during manufacturing.

Product Features:

Motorcraft spark plugs are matched to specific engines to provide enhanced durability, eliminate misfires, reduce fuel consumption and optimize emissions.
Backed by Motorcraft’s Service Parts Warranty
Exact fit for Ford, Lincoln and Mercury vehicles
Resistant to oxidation and arc erosion.
Multi-rib insulator protects against misfire.
Service intervals of up to 100,000 miles.
Motorcraft Spark Plugs are designed with high quality materials to provide reliable performance for almost any application.
Motorcraft Spark Plugs are what was in the vehicle when it was manufactured
Motorcraft ignition components help prevent false check engine lights.
Enhanced Durability: Engineered to meet strict Ford engineering standards, these spark plugs are designed to provide long-lasting performance and withstand harsh conditions.
Reduces Fuel Consumption: Specifically matched to engines to optimize fuel efficiency, helping you save on fuel costs.

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$52.99

ACCEL’s patented race proven spark plugs in a Shorty configuration. The overall length has been reduced 3/16 in to 3/8 in (depending on the specific spark plug) to gain critical air gap between the spark plug boot and the exhaust manifold or header tube. This helps eliminate burning the spark plug boot or dimpling the header tube. The shorter spark plug length also can make it easier to install an remove the spark plugs in certain applications where there is not a lot of room to fit a socket or move a wrench around. ACCEL Shorty Spark Plugs are made with a Copper core which is a better conductor than Platinum and Iridium. They deliver a stronger spark especially in high performance applications where high combustion pressures are present. Copper is much better at dissipating heat than other materials which lessens the chance of a misfire. ACCEL Shorty Spark Plugs are gapable allowing you to open the gap exposing a larger flame kernel or close it if needed for high boost applications. All ACCEL Shorty Spark Plugs have machine rolled threads allowing for a more precise thread engagement and torque retention.

Product Features:

Shorty Spark Plugs For Tubular Exhaust Headers
Eliminates Dimpling Headers For Added Clearance
Improves Spark Plug Access To Fit Socket Or Wrench
Shorter Overall Plug Length Vs. OE Style Plug
Copper Core Center Electrode
Projected Tip
Helps Eliminate Burned Spark Plug Boots
Shorty Header Spark Plug

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$11.99

NGK Iridium IX spark plugs are specifically designed for the performance enthusiast. Iridium IX provides outstanding acceleration, high fuel efficiency and durability. NGK Iridium IX plugs offer extreme ignitability and exceptional anti-fouling. Tapered cut ground electrode provides improved starting, idling and throttle response. The Iridium fine wire center electrode’s durability is six times harder than platinum. Iridium alloy’s extremely high melting point is perfect for today’s engines. For even greater performance consider upgrading to an NGK Ruthenium HX plug.

Product Features:

SINGLE IRIDIUM TIP: Fine wire 0.6 millimeter iridium tip center electrode ensures high durability and a consistently stable spark
IRIDIUM ALLOY CENTER ELECTRODE: Iridium’s density (6x that of platinum) and extremely high melting point is perfect for modern high efficiency engines
TAPERED CUT GROUND ELECTRODE: Reduced quenching design produces outstanding ignitability, improved acceleration, fuel efficiency and durability
SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
TRIVALENT METAL PLATING: Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal
RECOMMENDED USAGE: Modified or high performance applications, or as an upgrade to OE nickel alloy spark plugs
Outstanding Acceleration and High Fuel Efficiency: NGK Iridium IX spark plugs are engineered to deliver exceptional acceleration and improved fuel efficiency, making them ideal for performance enthusiasts.
Extreme Ignitability and Anti-Fouling: These spark plugs offer extreme ignitability and exceptional resistance to fouling, ensuring reliable performance in various driving conditions.

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$7.29

Motorcraft Spark Plugs are original equipment on Ford Motor Company vehicles, engineered to meet strict Ford engineering standards for performance and reliability. These spark plugs are matched to specific engines to provide enhanced durability, eliminate misfires, reduce fuel consumption, and optimize emissions. With a platinum center and ground electrode tip, they are resistant to oxidation and arc erosion, ensuring long-lasting performance. The multi-rib insulator protects against misfire, and they are backed by Motorcraft’s Service Parts Warranty. Designed for exact fit in Ford, Lincoln, and Mercury vehicles, they also help prevent false check engine lights. With service intervals of up to 100,000 miles, Motorcraft Spark Plugs are crafted from high-quality materials to deliver reliable performance for almost any application, making them the same components that were in the vehicle when it was manufactured.

Product Features:

Motorcraft spark plugs are matched to specific engines to provide enhanced durability, eliminate misfires, reduce fuel consumption and optimize emissions.
Backed by Motorcraft’s Service Parts Warranty
Exact fit for Ford, Lincoln and Mercury vehicles
Resistant to oxidation and arc erosion.
Multi-rib insulator protects against misfire.
Service intervals of up to 100,000 miles.
Motorcraft Spark Plugs are designed with high quality materials to provide reliable performance for almost any application.
Motorcraft Spark Plugs are what was in the vehicle when it was manufactured
Motorcraft ignition components help prevent false check engine lights.
Enhanced Durability: Engineered with a platinum center and ground electrode tip, these spark plugs are resistant to oxidation and arc erosion, ensuring long-lasting performance.

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$3.99

Champion® Platinum Power spark plugs deliver powerful performance with their premium design. Featuring a platinum center electrode for long life and a fine-wire center electrode for greater ignitability, these spark plugs ensure optimal engine performance. The V-trimmed ground electrode promotes sharper spark focus, while the exclusive Heat-Active alloy allows the electrodes to reach optimal temperature. Additionally, the platinum-tipped center wire resists wear and helps maintain the proper gap specification throughout the life of the plug. With a flat seat type and integrated resistor, this spark plug is an ideal OE replacement.

Product Features:

Platinum Power- Premium Spark Plug. Powerful Performance.
Platinum center electrode for long life
Fine-wire center electrode for greater ignitability
V-trimmed ground electrode promotes sharper spark focus
Heat-Active alloy allows electrodes to reach optimal temperature
Platinum tipped center wire resists wear and helps to maintain proper gap spec over life of the plug
Integrated Resistor and Flat Seat Type: Equipped with an integrated resistor and flat seat type, making it an ideal OE replacement for various engines.

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$9.79

ACDelco GM Original Equipment Double Platinum Spark Plugs are designed, engineered, and tested to rigorous standards, and are backed by General Motors. With a copper core and double platinum pads on the center electrode, these plugs are designed to deliver long-lasting performance. ACDelco GM Original Equipment parts are the true OE parts installed during the production or validated by General Motors for GM vehicles. Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional.

Product Features:

One-piece, fired-in suppressor seal blends three glass types for a gas-tight seal that helps reduce radio frequency and engine interference, regulate spark plug energy, and protect against compression pressures for long life
Double platinum point pad on center and ground electrode offer excellent durability and consistent voltage demands to help reduce wear on ignition system
Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional
ACDelco GM Original Equipment parts are designed, engineered and tested to rigorous standards, and are backed by General Motors
GM Engineers design and validate OE parts specifically for your Chevrolet, Buick, GMC, or Cadillac vehicle
GM regularly updates production and service part designs to integrate new materials and technologies
Copper Core: Designed with a copper core to provide excellent heat transfer and electrical conductivity.
Conical Seat Type: Equipped with a conical seat type for a secure fit and optimal performance.

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$7.49

The Spark Plugs are the product of years of fundamental research in the combustion field. The unique patented electrode configuration of these new The spark plugs increases the amount of combustion pressure created during each power stroke of an engine, which results in a marked increase in power output, fuel economy, and reduced emissions in all gasoline engines. E3.46 is a 14mm, 0.750 reach plug with a gasket seat. It fits a wide variety of applications from the 60s to early 90s, especially import. E3.46 is widely stocked in automotive retail stores. The automotive plugs have three legs securing the Diamond FIRE electrode to the shell. This allows for excellent heat transfer, and helps to create more turbulence in the cylinder. The patented Diamond FIRE side wire is proven to increase power, reduce fuel consumption and improve hydrocarbon emissions in long-term use.

Product Features:

E3’s Diamond Fire edge to edge ground electrode provides maximum performance with increased efficiency and a faster more complete burn.
Smoother Acceleration & Idle – The faster flame initiated by the The spark plug results in a more complete burn of the ingested fuel charge. More pressure is created against the piston more fuel is put to work
Energy – Power output improved up to 6% on average in the typical operating ranges. Results will vary.
Efficiency – The “diamond shaped” side wire electrode projects the combustion spark in a way that more quickly ignites the air/fuel mixture, thereby creating a significantly faster and larger flame kernel. The result is that more fuel is put to work durin
E3’s patented Diamond Fire Technology provides a cleaner burning combustion, which translates into fuel savings and reduced engine carbon deposits
The Spark Plugs are pre-gapped at the factory and cannot be adjusted.
Wide Compatibility: The E3.46 spark plugs are 14mm with a 0.750 reach and a gasket seat, making them suitable for a wide range of applications from the 1960s to early 1990s, especially for import vehicles.
Widely Available: The E3.46 spark plugs are widely stocked in automotive retail stores, ensuring easy availability for consumers.

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$6.49

With over 100 years of engineering expertise and more than 11 billion plugs sold, Autolite delivers exceptional quality. Designed and engineered in the USA, these spark plugs feature platinum-to-platinum firing, virtually eliminating gap erosion and reducing misfires. The OE design and full-platinum tips on both the center and side electrodes optimize engine performance for a longer life and improved fuel economy. The platinum ball welding process ensures a consistent point of contact for enhanced adhesion, while the tapered seat type further contributes to the plug’s superior durability.

Product Features:

Works to optimize engine performance for a longer life and improved fuel economy
OE design
Full-platinum tips; platinum on both the center and side electrodes to promote reduced gap wear
Platinum ball welding process provides a consistent point of contact for enhanced adhesion
Engineered in the USA: Backed by over 100 years of engineering expertise and more than 11 billion plugs sold, Autolite spark plugs are designed and engineered in the USA for exceptional quality and reliability.

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$4.49

Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Designed and engineered in the USA, Autolite Platinum spark plugs provide a center wire platinum firing tip which provides reduced gap erosion, fewer misfires, better performance and increased durability. Consider upgrading to Autolite Double Platinum or Iridium XP spark plugs for increased performance.

Product Features:

High nickel alloy side electrode maintains precise gap
Full platinum tip assures virtually no gap erosion for long life
Necked-down center electrode fires quicker, cleaner with less voltage for easier starts, quicker acceleration and improved fuel economy (as compared to standard plugs)

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$3.49

Dependable performance. This Champion® spark plug features a copper core electrode that provides increased conductivity and heat control for good overall wear.

Product Features:

Copper Plus – Dependable Performance and Durability
Copper core center electrode allows for accurate control of heat range for longer life
Superior corrosion resistance
Built to ISO and SAE standards for proven performance
Built to ISO and SAE standards for proven performance

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$2.79

Dependable Performance, OE Replacement, RS14YC. This Champion® spark plug features a copper core electrode that provides increased conductivity and heat control for good overall wear. The Copper Plus design ensures dependable performance and durability, while the copper core center electrode allows for accurate control of heat range, extending the spark plug’s life. Built to ISO and SAE standards, it offers superior corrosion resistance and proven performance. The nickel center electrode tip and tapered seat type further enhance its reliability, making it an excellent choice for maintaining your engine’s efficiency.

Product Features:

Copper Plus – Dependable Performance and Durability
Copper core center electrode allows for accurate control of heat range for longer life
Superior corrosion resistance
Built to ISO and SAE standards for proven performance
Built to ISO and SAE standards for proven performance
Nickel Center Electrode Tip and Tapered Seat: Equipped with a nickel center electrode tip and a tapered seat type, this spark plug ensures optimal performance and reliability for your engine.

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$65.99

These ACCEL wire sets are a true performance upgrade replacement for OE types. Efficient delivery of spark energy for a good price. Silicone boots with black wire contain zinc-plated steel terminals. Noise suppression core. Set contains 8 plug wires with coil lead.

Product Features:

7mm And 8mm High Gloss Silicone Jacket
450° F Rated Silicone Jacket
Stainless Steel Plug Terminals
RFI Suppression For Street Driven Applications
Custom-fit Universal And Import Coverage
High-strength Fiberglass Braid Construction
Pre And Post HEI Vehicles

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$129.99

For engines with late-model type (HEI spark plug top) distributor caps. Multi-angle boots and terminals installed on one end. 90 degree distributor boots and terminals included.

Product Features:

Extra Long 8.5mm Wires So You Can Cut To Your Designed Length
Distributor Cap – Boots and Terminals Included
Includes Mini-Stripper-Crimper For Factory Style Crimps
Size Includes [8] 90 Degree Boots/Terminal Ends
Durable outer sleeve is a proprietary compound for resistance to high heat or abrasion
Stainless steel terminals feature dual crimp tabs to grip wire conductor and outer jacket separately

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$72.99

These ACCEL Super Stock wire sets are a true performance upgrade replacement for OE types. Efficient delivery of spark energy for a good price. Silicone boots with zinc-plated steel terminals.

Product Features:

Tinned copper core allows virtually no resistance
Great for points and magneto
450 Degree Wire Temperature Rating
Meets Or Exceeds OE Boot Temperature Rating

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$63.99

These ACCEL wire sets are a true performance upgrade replacement for OE types. Efficient delivery of spark energy for a good price. Silicone boots with black wire contain zinc-plated steel terminals. Noise suppression core. Set contains 8 plug wires with coil lead.

Product Features:

7mm And 8mm High Gloss Silicone Jacket
450° F Rated Silicone Jacket
Stainless Steel Plug Terminals
RFI Suppression For Street Driven Applications
Custom-fit Universal And Import Coverage
High-strength Fiberglass Braid Construction

1974 Ford Mustang II Spark Plugs

More 1974 Ford Mustang II Spark Plugs

Essential 1974 Ford Mustang II Spark Plugs

Autolite – Racing Resistor Spark Plug: Enables Performance, Handles Intense Conditions (Part No.AR25)

DENSO – Iridium Power Spark Plug: Maximum Spark Energy, 0.4mm Iridium Tip, ITF16 (Part No.5330)

Autolite – Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration (Part No.106)

Motorcraft – Standard Spark Plug: Enhances Durability & Reduces Fuel Consumption (Part No.SP-425-A)

Accel – High-Performance Shorty Spark Plugs for Header Clearance (Part No.8199)

NGK – Iridium IX Spark Plug: Single Iridium Fine Wire, TR5IX (Part No.7397)

Motorcraft – Double Platinum Spark Plug: Enhances Durability & Reduces Misfires (Part No.SP-486)

Champion – Platinum Power Spark Plug: Powerful Perfromance, OE Replacement, RN14PMC (Part No.3405)

ACDelco – Double Platinum Spark Plug: Original Equipment Replacement (Part No.41-950)

E3 – DiamondFIRE Automotive Spark Plug: More Power, Saves Gas (Part No.E3.46)

Autolite – Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life (Part No.APP26)

Autolite – Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration (Part No.AP25)

Champion – Copper Plus Spark Plug: Dependable Performance, OE Replacement, RV17YC (Part No.25)

Champion – Copper Plus Spark Plug: Dependable Performance, OE Replacement, RS14YC (Part No.408)

Accel – Universal Fit Super Stock 8mm Suppression; Spark Plug Wire Set (Part No.4040R)

MSD Ignition – Wire Set; Super Conductor; Multi-Angle Plug; HEI Cap (Part No.31189)

Accel – 8Mm Super Stock Copper Uni (Part No.4038B)

Accel – Universal Fit Super Stock 8mm Suppression; Spark Plug Wire Set (Part No.4040)

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1974 Ford Mustang II Spark Plugs

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