Showing specs for all NA & NB Miatas

Cylinder head height (NA6)

Height: 5.268–5.276 in (133.8–134.0 mm)Height: 133.8–134.0 mm (5.268–5.276 in)

Factory manualTaken from a Mazda factory workshop manual, with page citation.
Procedure

Replace the cylinder head if its height is outside this specification.

Applies to
  • NA 1990–1993 (B6) — Other years inferred from 1990 factory evidence.
  • Verified in: 1990 Mazda MX-5 Miata Workshop Manual