PCI Adjustable Left Side Seat Mount - NA/NB Miata (90-05)

Upgrade your 1989-2005 NA/NB Mazda MX‑5 (Miata) with the driver-side adjustable seat mount from Pro Car Innovations — the SM-90MX5-L-A1. This high-performance mounting solution is crafted from a single piece of 3 mm (1/8″) carbon steel, precision CNC laser cut and bent for maximum strength, rigidity and weight reduction. The design delivers equal or greater stiffness than conventional 3/16″ welded mounts while maintaining lower profile and superior adjustability.

With multi-directional adjustability (width, fore/aft travel) and support for both 5-point and 6-point sub-belt harness systems, this mount is ideal for both street performance builds and full-on track machines. It bolts directly into factory mounting points for the NA/NB chassis with no guesswork required, making installation cleaner and faster.

Finished in a gloss black metallic powder coat, and equipped with zinc-plated grade 8 hardware plus included ¼″ × 1.25″ black nylon spacers, the SM-90MX5-L-A1 balances form and function flawlessly. The width adjustment spans roughly 12 5/8″ (320 mm) to 18 ½″ (467 mm) for most applications (with a 1″-narrow exception for MX-5), and offers approximately 6″ (152 mm) of fore/aft adjustment.

Whether you’re building an autocross-ready Miata, a track-focused club car, or simply upgrading your street machine for improved seat fitment and positioning — this driver-side mount gives you the control, adjustability and strength you demand for serious driving.