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Product Information

Product Details
Part No. AR25
Warranty Details (2 YR REPLACEMENT IF DEFECTIVE)
Racing Resistor Spark Plug is expertly crafted to deliver peak performance in competitive racing environments. Featuring a cut-back ground electrode, it ensures optimal ignitability and superior heat transfer for quicker starts and maximum engine efficiency. The yttrium-enhanced alloy reduces ground wire temperature by up to 8%, making it ideal for colder heat ranges and performance modifications. Its anti-corrosive nickel plating resists rust better than black oxide, ensuring long-lasting durability. Designed with a high alumina multi-rib ceramic insulator, it offers exceptional thermal conductivity and insulation, preventing flash-over and enhancing strength. The tapered seat type optimizes performance across various racing venues, from oval tracks to road circuits. Built to withstand intense conditions, this spark plug is compatible with all aftermarket cylinder heads used in competitive racing. With a mid-projection center electrode and nickel tip materials, it combines reliability and efficiency, making it a top choice for racers seeking consistent, high-performance ignition.

Product Features:
  • Engineered with a cut-back ground electrode that delivers optimal ignitability of the flame kernel and better heat transfer, leading to quicker starts.
  • The yttrium-enhanced alloy enables up to 8% reduction in ground wire temperature for colder heat ranges designed to enable performance modifications and handle intense conditions.
  • Designed with an anti-corrosive nickel-plating prevents rusting better than black oxide, allowing the plug to maintain its durability and efficiency.
  • Its high alumina multi-rib ceramic insulator provides thermal conductivity and superior insulation for increased strength while preventing flash-over.
  • 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.
Specifications
Center Electrode Core Material:
Copper

Center Electrode Design:
Standard

Center Electrode Projection:
Mid Projection

Center Electrode Tip Material:
Nickel

Electrical Terminal Type:
Non-Removable Nut

Electrode Tip Material:
Resistor

Grade Type:
Performance

Ground Electrode Core Material:
Nickel

Ground Electrode Quantity:
1

Ground Electrode Tip Design:
Standard

Ground Electrode Tip Material:
Nickel

Hex Size:
5/8 in

Hex Type:
Hex

Indexed:
No

Insulator Material:
Ceramic

Manufacturer Heat Range:
8

Pre-Gap Size:
0.044 in

Reach:
0.431 in

Resistor:
Suppressor

Resistor Type:
Yes

Seat Type:
Tapered

Skirt:
No

Thread Diameter:
14 mm

Tip Configuration:
Power

Washer(s) Included:
No

Wrench Diameter:
5/8 in
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