Spark Plug TR6 4177 V-Power, Pre-Set Gap: 0.040" 1-PLUG

NGK TR6 4177 V-Power Spark Plug – Pre-Set Gap 0.040" (Single Plug)

NGK TR6 (stock #4177) is a V-Power copper spark plug in a colder heat range than the TR5, making it a popular choice for mildly modified or lightly boosted engines. The V-grooved nickel center electrode and copper core help improve ignitability and detonation resistance compared to basic plugs, while still working well for street-driven combos. This listing is for one plug, pre-gapped to 0.040".

• Brand: NGK

• Series: V-Power

• Part Number: TR6

• Stock Number: 4177

• Product Type: Spark plug – sold individually (1 plug)

Electrode & Core

• Center Electrode Core Material: Copper

• Center Electrode Design: Standard

• Center Electrode Tip Material: Nickel

• Ground Configuration: J-gap

• Ground Electrode Quantity: 1

• Ground Electrode Core Material: Nickel

• Ground Electrode Tip Design: Standard

• Ground Electrode Tip Material: Nickel

Size & Fit

• Thread Size: M14 x 1.25 (14 mm, metric)

• Reach: 0.689" (17.5 mm)

• Seat Type: Tapered

• Hex Size: 5/8" (16 mm)

• Short Style Plug: No

Electrical & Heat Range

• Resistor Type: Yes

• Heat Range: 6 (one step colder than TR5 on the NGK scale)

• Electrical Terminal Type: Removable nut

Gap & Setup

• Pre-Set Gap: 0.040" (1.0 mm) – always verify and adjust to your tuner/engine spec

Materials

• Insulator Material: Ceramic

• Material Grade: Nickel/Copper

Use as a single replacement or order the quantity you need (e.g. 8 for most V8s), especially on mildly modified or lightly boosted combos that call for a colder TR6 plug.