# Piston pin hole diameter (NA8)

Canonical URL: https://miatatorque.com/spec/piston-pin-hole-diameter-na8/

Applicability: NA 1994–1997 (BP) — Other years inferred from 1994 factory evidence.

Confidence: fsm

Diameter: 19.988—20.000mm {0.7870—0.7874 in}

Always confirm against your factory manual. Match every restriction and follow all stages and procedure notes. Disputed claims must not be automatically resolved. The complete record below preserves every printed unit, source claim and procedure.

```json
{
  "id": "piston-pin-hole-diameter-na8",
  "name": "Piston pin hole diameter (NA8)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NA",
      "years": [
        1994,
        1997
      ],
      "engines": [
        "BP"
      ],
      "note": "Other years inferred from 1994 factory evidence."
    }
  ],
  "kind": "non-torque",
  "value_text": "Diameter: 19.988—20.000mm {0.7870—0.7874 in}",
  "procedure": {
    "notes": "Measure in X and Y directions at four specified points."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-1994",
      "page": "B–56 (PDF p. 93)",
      "as_printed": "Diameter: 19.988—20.000mm {0.7870—0.7874 in}",
      "verified_years": [
        1994,
        1994
      ],
      "document": {
        "id": "fsm-1994",
        "tier": 1,
        "title": "1994 Mazda MX-5 Miata Workshop Manual",
        "covers": [
          {
            "gen": "NA",
            "years": [
              1994,
              1997
            ],
            "engines": [
              "BP"
            ]
          }
        ],
        "note": "Mazda's base manual for 1994–97; later model years got supplements, which we haven't checked yet."
      }
    }
  ],
  "jobs": [],
  "system": "engine",
  "component": "inventory-pass-2026-10",
  "componentName": "Service measurements and fasteners",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/piston-pin-hole-diameter-na8/"
}
```