Ignitions and Electrical› Ignition Components

Denso

U-Groove Spark Plug

$6.95

SKU: K20HR-U11

In Stock
In Stock
Ships by Sep 13
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
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Easy — 1–2 hours

Overview

The Denso 3381 K20HR-U11 is a nickel U-groove spark plug designed for improved performance. Its U-shaped groove in the ground electrode allows the flame to grow, leading to less dissipation and a larger flame front for more complete combustion. This design contributes to better fuel efficiency and improved throttle response.
Show original supplier description
The Denso 3381 K20HR-U11 spark plug features a unique U-groove design in its ground electrode. This specialized groove allows the flame kernel to expand more freely, resulting in less flame dissipation and a larger, more robust flame front. This enhanced combustion process translates directly into improved fuel efficiency and a more responsive throttle. Constructed with a purified alumina powder insulator, this spark plug offers exceptional strength and thermal conductivity. The five-rib insulator design helps prevent flashover, ensuring reliable ignition. A copper-glass seal reliably bonds the center electrode and insulator, creating a gas-tight seal. The center electrode is made of nickel with a standard 2.5mm size, and the ground electrode is also nickel with a U-groove type and a single ground electrode. Machine-rolled threads are incorporated to prevent seizing or cross-threading during installation and removal. Each plug is 100% pre-fired to guarantee the highest quality. Key specifications include a 14mm thread diameter, 1.25mm thread pitch, gasket seat type, 26.5mm reach, and a 5/8" (16mm) hex size. This is a resistor-type plug with a value of 5k Ohm, and the specified gap is .043" (1.1mm). Torque specifications vary by cylinder head material: 26-30 lb. ft. for cast iron and 15-22 lb. ft. for aluminum.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandDenso
Part NumberK20HR-U11
CategoryIgnitions and Electrical

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Shipping

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