Mazda 12A Rotary 12.7mm Stud Kit – High-Strength Sealing Upgrade

Upgrade the integrity of your Mazda 12A rotary engine with our high-strength 12.7mm stud kit — engineered for builders chasing serious performance, sealing pressure, and engine longevity.

Machined in-house from premium-grade 12.7mm (1/2") high-tensile steel, these studs offer significantly increased clamping force compared to factory hardware, helping to reduce engine movement under boost or high RPM — ideal for naturally aspirated or forced induction builds alike.

Whether you're restoring a classic RX or pushing for peak numbers at the strip or on the dyno, this stud kit delivers the strength and reliability your 12A bottom end needs.

🔧 What's Included:

• Complete set of 12.7mm engine studs
• Heavy-duty washers & nuts
• Designed for precise fitment in OEM and aftermarket 12A engine housings

🌍 Fitment Applications – Local & Global:

• Mazda RX-2 – Locally delivered in Australia and popular in North America & Asia
• Mazda RX-3 – Sold in Australia, Japan, New Zealand, USA & parts of Europe
• Mazda RX-4 – Available in Australia and global export markets including the US & UK
• Mazda RX-7 Series 1 & 2 (SA/FB) – Early 12A-equipped models sold worldwide from 1978 to 1983
• Rotary engine conversions – Widely used in grassroots motorsport, classic JDM builds, and restoration projects worldwide

This stud kit suits any 12A rotary engine application — whether it’s an Aussie-delivered RX-3, a US-spec RX-2, or a custom 12A swap running high boost or RPM.

📦 Built by Enthusiasts:

Proudly manufactured in Australia by Milton Engine Developments, trusted by rotary specialists across the globe.

📌 Note:

If you’re unsure of compatibility with your build, or need something that isn’t listed, please contact us before ordering.