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Bosch WR9LS Silver Spark Plug 14mm 0.028" Gap Resistor

(1985-1988 BMW 535i; 1985-1987 BMW 635CSi; 1984-1987 BMW 325e; 1982-1987 BMW 528e; 1985-1987 BMW 735i; 1982-1984 BMW 633CSi; 1986-1988 BMW 325 + 5 more models)

Manufacturer

Picture for manufacturer Bosch

Part Number

WR9LS
10 reviews
Sale Price

$6.32

1 left at this price

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Usually delivered within 2 days

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Live-in-stock inventory

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Fitment guaranteed

Fitment guaranteed

Product Details

The Bosch WR9LS Silver Spark Plug is engineered specifically for older European performance cars and select motorcycle applications that operate at particularly high combustion chamber temperatures. The silver alloy center electrode tip resists material erosion under these demanding thermal conditions while delivering consistent, efficient ignition performance.

Unlike conventional copper or nickel electrode plugs, Bosch silver alloy construction provides superior conductivity and wear resistance at elevated temperatures — making the WR9LS the correct OE-specification choice for applications where engine heat would accelerate degradation in standard plugs.

Key Features:

  • Silver alloy center electrode tip for improved spark efficiency and resistance to high-temperature erosion
  • Projected electrode design for optimal flame kernel development
  • Five-rib ribbed ceramic insulator prevents misfires caused by flash-over and current leakage
  • Nickel-plated rolled threads provide superior corrosion resistance — no anti-seize compound required
  • Removable terminal nut for compatibility with multiple ignition cable configurations
  • Pre-gapped at 0.028" (0.7mm) — ready to install out of the box

Specifications:

  • Thread Diameter: 14mm
  • Thread Pitch: 1.25mm
  • Reach: 19mm (0.750 in.)
  • Seat Type: Gasket
  • Hex Size: 13/16" (21mm)
  • Gap: 0.028" (0.7mm)
  • Center Electrode Material: Silver
  • Ground Electrode Material: Nickel
  • Center Electrode Type: Projected / Standard
  • Terminal Type: Removable Nut
  • Resistor: Yes
  • Heat Range: 9
  • Bosch OEM Part Number: 0242225539

Sold individually. Bosch OEM cross-references include: 12121279599.

Products specifications

Fits

1985-1988 BMW 535i; 1985-1987 BMW 635CSi; 1984-1987 BMW 325e; 1982-1987 BMW 528e; 1985-1987 BMW 735i; 1982-1984 BMW 633CSi; 1986-1988 BMW 325; 1986-1987 BMW 325es; 1982-1984 BMW 733i; 1983-1984 BMW 533i; 1987 BMW L6; 1986-1987 BMW L7

Electrode Core Material

Silver

Electrode Tip Material

Silver

Ground Strap Quantity

One

Manufacturer Heat Range

9

Quantity

Sold individually.

Shorty Spark Plug

No

Spark Plug Reach

0.750 in.

Spark Plug Seat Style

Gasket

Spark Plug Thread Size

14mm

Wrench Diameter

13/16 in.

The quality of the product was perfect and ordering from the sight was really simple

Quick and easy

Parts have not been put on yet will contact on how it goes

Great transaction, great price

Great service & fast delivery!

All Good

Fast service and shipping, Plus the lowest price for the high performance k&n air filter<br>I wanted.

very fast processing received product within a few days. fair prices. will do business with again.

cool site i actually got the part for 1/3 the cost and free shipping pretty rad!

Completely amazed by this seller. I recieved the rack in just 2 days and the price was unbeatable. I'm just stoked to have finally found a bike rack worth having!!

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