# Piston ring end gap (NA8)

Canonical URL: https://miatatorque.com/spec/piston-ring-end-gap-na8/

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

Confidence: fsm

End gap
Top: 0.15—0.30mm {0.006—0.011 in}
Second: 0.15—0.30mm {0.006—0.011 in}
Oil rail: 0.20—0.70mm {0.008—0.027 in}
Maximum: 1.0mm {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-na8",
  "name": "Piston ring end gap (NA8)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NA",
      "years": [
        1994,
        1997
      ],
      "engines": [
        "BP"
      ],
      "note": "Other years inferred from 1994 factory evidence."
    }
  ],
  "kind": "non-torque",
  "value_text": "End gap\nTop: 0.15—0.30mm {0.006—0.011 in}\nSecond: 0.15—0.30mm {0.006—0.011 in}\nOil rail: 0.20—0.70mm {0.008—0.027 in}\nMaximum: 1.0mm {0.039 in}",
  "procedure": {
    "notes": "Procedure starts B–55/PDF92: insert ring and use piston to push squarely to bottom of ring travel; measure with feeler gauge. Maximum applies to the listed ring types."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-1994",
      "page": "B–56 (PDF p. 93)",
      "as_printed": "End gap\nTop: 0.15—0.30mm {0.006—0.011 in}\nSecond: 0.15—0.30mm {0.006—0.011 in}\nOil rail: 0.20—0.70mm {0.008—0.027 in}\nMaximum: 1.0mm {0.039 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-ring-end-gap-na8/"
}
```