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Autolite Racing Resistor Spark Plug: Engineered for Maximum Track Performance

(28 reviews)
Part # AR103
2 year warranty
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Product Information

Product Details
Part No. AR103
Warranty Details (2 Year Warranty)
Racing Resistor Spark Plug is expertly crafted to deliver peak performance on the track, featuring a cut-back ground electrode for optimal ignitability and enhanced 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 intense racing 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 superior thermal conductivity and insulation, preventing flash-over while increasing strength. The tapered seat type ensures optimal performance across various racing venues, including oval and road racing, while its durable design is tailored for aftermarket cylinder heads. With a mid-projection nickel center electrode and nickel ground electrode tip, this performance-grade spark plug is built to handle the demands of high-speed racing, delivering reliability and value for serious competitors.

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: Specifically designed to handle intense conditions, making it suitable for all aftermarket cylinder heads used in racing.
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:
0.034 in

Reach:
0.679 in

Resistor:
Suppressor

Resistor Type:
Yes

Seat Type:
Tapered

Skirt:
Yes

Thread Diameter:
14 mm

Tip Configuration:
Power

Washer(s) Included:
No

Wrench Diameter:
5/8 in
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4.79 out of 5
28 Customer Reviews
100% of respondents would recommend this to a friend
Ratings Distribution
5 Stars
23
4 Stars
4
3 Stars
1
2 Stars
0
1 Star
0
ExcelentExcelentGreat plugs
Auto lite plugs
Pros
2
Easy To Install
1
Durable
Cons
No Cons
Best Uses
1
Performance Driving
1
Racing
1
Replacement
Describe Yourself
1
Casual Driver
1
Competitive Driver
1
Mechanic
Most Liked Positive Review
Best spark plug
PLACEMENT PART FOR TUNE UP
Most Liked Negative Review
see comments
I was sent 6 of these plugs, and 2 Bosch Spark plugs. I don't know why this happened, but I ordered 8 Autolites, and should have received 8 of them, not 6 and then 2 random Spark plugs that I didn't want. Shipping dept screwed this up.
Reviewed by 28 Customers
see comments
Staff Reviewer -
I was sent 6 of these plugs, and 2 Bosch Spark plugs. I don't know why this happened, but I ordered 8 Autolites, and should have received 8 of them, not 6 and then 2 random Spark plugs that I didn't want. Shipping dept screwed this up.
Best spark plug
Staff Reviewer -
PLACEMENT PART FOR TUNE UP
Bottom Line Yes, I would recommend to a friend
Yes
Verified Buyer -
I use this plug in my foxbody mustang with aluminium heads and they do good .
Autolite AR103
Verified Buyer -
See the Focusfanatics /Ford Focus web site "spark plug sassticky" for application of Autolite A103, A104 and AR103 -- The AR 103 gapped at .055 works great -- estimate for plug service is 15,000 miles --- Application here for 2.3 liter Duratec with automatic --- would consider that application with manual transmission would show some gains , too, in smooth idle, mpg.
Great plugs
Verified Buyer -
Great plugsrunning in my sbc aluminum heads.
Displaying Reviews 1 - 5Back to Top
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