# Piston ring end gap (Mazdaspeed)

Canonical URL: https://miatatorque.com/spec/piston-ring-end-gap-msm/

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

Confidence: fsm

Standard end gap
Top : 0.15—0.30 mm {0.006—0.011 in}
Second : 0.30—0.45 mm {0.012—0.017 in}
Oil rail : 0.20—0.70 mm {0.008—0.027 in}
Maximum end gap
1.0 mm {0.039 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-ring-end-gap-msm",
  "name": "Piston ring end gap (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": "Standard end gap\nTop : 0.15—0.30 mm {0.006—0.011 in}\nSecond : 0.30—0.45 mm {0.012—0.017 in}\nOil rail : 0.20—0.70 mm {0.008—0.027 in}\nMaximum end gap\n1.0 mm {0.039 in}",
  "procedure": {
    "notes": "Use a piston to push each ring squarely to the bottom of ring travel, then measure with a feeler gauge."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "workshop-bp-turbo-2004",
      "page": "01–10–23 (PDF p. 35)",
      "as_printed": "Standard end gap\nTop : 0.15—0.30 mm {0.006—0.011 in}\nSecond : 0.30—0.45 mm {0.012—0.017 in}\nOil rail : 0.20—0.70 mm {0.008—0.027 in}\nMaximum end gap\n1.0 mm {0.039 in}",
      "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-ring-end-gap-msm/"
}
```