Autolite XP666 Spark Plug
Specs, cross-brand equivalents, vehicle fitment, and live prices for the Autolite XP666.
The Autolite XP666 is a iridium electrode spark plug. These specifications are decoded from the Autolite part number and determine which plugs it safely cross-references to — a valid equivalent must match the thread, reach, seat and heat range.
Cross-reference equivalents
| Brand | Part | Metal | Buy |
|---|---|---|---|
| Denso | ITF16 | Iridium | Buy |
| Motorcraft | ASF42P | — | Buy |
| ACDelco | 41-826 | — | Buy |
| Autolite | APP666 | Double Platinum | Buy |
| Autolite | AR25 | — | Buy |
| Autolite | XP26 | Iridium | Buy |
| Autolite | XP26DP2 | Iridium | Buy |
| Bosch | 6210 | — | Buy |
| Bosch | 9659 | — | Buy |
| Bosch | HGR9BQI(Pt-IR FUSION) | Copper | Buy |
| Bosch | HR8BP | Platinum | Buy |
| Bosch | HR9BII33V | Iridium | Buy |
| Bosch | HR9BPY | Platinum | Buy |
| Bosch | HR9BPZ | Platinum | Buy |
| Champion | 7018(Double-Pt) | Copper | Buy |
| Denso | 267700-0660 | — | Buy |
| Denso | 5330 | — | Buy |
| NGK | 7559 | — | Buy |
| NGK | UR45IX | Iridium | Buy |
| Split Fire | SF2E | — | Buy |
| P4RTI | — | Buy | |
| P4RTP | — | Buy |
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