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Product Information

Product Details
Part No. AR3923
Warranty Details (2 YR REPLACEMENT IF DEFECTIVE)
The Racing Resistor Spark Plug is expertly crafted to deliver peak performance on the track, featuring a cut-back ground electrode for optimal ignitability and superior heat transfer, ensuring quicker starts and maximum engine efficiency. Its yttrium-enhanced alloy reduces ground wire temperature by up to 8%, making it ideal for colder heat ranges and performance modifications under intense conditions. The anti-corrosive nickel plating resists rust better than black oxide, maintaining durability and long-term efficiency. Designed with a high alumina multi-rib ceramic insulator, it offers exceptional thermal conductivity and insulation, preventing flash-over while enhancing strength. With a mid-projection center electrode and nickel-tipped components, this performance-grade spark plug is built to handle the demands of racing environments, delivering reliability and value for enthusiasts seeking top-tier engine performance.

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.
  • Built with a mid-projection center electrode and nickel-tipped components, this spark plug ensures reliable performance under demanding racing conditions, offering durability and consistent engine efficiency for enthusiasts.
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:
10

Pre-Gap Size:
0.044 in

Reach:
0.75 in

Resistor:
Suppressor

Resistor Type:
Yes

Seat Type:
Flat

Skirt:
Yes

Thread Diameter:
14 mm

Tip Configuration:
Power

Washer(s) Included:
Yes

Wrench Diameter:
5/8 in
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