# Piston diameter by size (Mazdaspeed)

Canonical URL: https://miatatorque.com/spec/piston-diameter-msm/

Applicability: NB 2004–2005 (BP-Z3-TURBO) — 2004 factory turbo-engine evidence; 2005 inferred within MSM family.

Confidence: fsm

Piston diameter
mm {in}
Size Diameter
Standard 82.953—82.975
{3.2659—3.2667}
0.25 {0.01} oversize 83.203—83.225
{3.2758—3.2765}
0.50 {0.02} oversize 83.453—83.475
{3.2856—3.2864}

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-diameter-msm",
  "name": "Piston diameter by size (Mazdaspeed)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NB",
      "years": [
        2004,
        2005
      ],
      "engines": [
        "BP-Z3-TURBO"
      ],
      "note": "2004 factory turbo-engine evidence; 2005 inferred within MSM family."
    }
  ],
  "kind": "non-torque",
  "value_text": "Piston diameter\nmm {in}\nSize Diameter\nStandard 82.953—82.975\n{3.2659—3.2667}\n0.25 {0.01} oversize 83.203—83.225\n{3.2758—3.2765}\n0.50 {0.02} oversize 83.453—83.475\n{3.2856—3.2864}",
  "procedure": {
    "notes": "Measure perpendicular to the pin, 16.5 mm below the lower edge of the oil-ring groove."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "workshop-bp-turbo-2004",
      "page": "01–10–23 (PDF p. 35)",
      "as_printed": "Piston diameter\nmm {in}\nSize Diameter\nStandard 82.953—82.975\n{3.2659—3.2667}\n0.25 {0.01} oversize 83.203—83.225\n{3.2758—3.2765}\n0.50 {0.02} oversize 83.453—83.475\n{3.2856—3.2864}",
      "verified_years": [
        2004,
        2004
      ],
      "document": {
        "id": "workshop-bp-turbo-2004",
        "tier": 1,
        "title": "2004 Mazda Engine Workshop Manual BP (1.8L), normally aspirated and turbo",
        "part_number": "9999-95-EWBP-04",
        "covers": [
          {
            "gen": "NB",
            "years": [
              2004,
              2004
            ],
            "engines": [
              "BP-Z3-TURBO"
            ],
            "trans": [
              "6MT"
            ]
          }
        ]
      }
    }
  ],
  "jobs": [],
  "system": "engine",
  "component": "inventory-pass-2026-10",
  "componentName": "Service measurements and fasteners",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/piston-diameter-msm/"
}
```