R Theory NA/NB Miata Stainless Frame Rail Braces (1990-2005)

Frame rail braces that slip over the Miata's factory frame rails and bolt through the floor, stiffening one of the chassis' weakest areas. R Theory Motorsports laser cuts and bends them from 304 stainless steel with no cut-outs, so a set weighs 15.7 lb. They also protect the factory rails from speed bumps and curbs and give a solid place to jack the car and set stands.

The backing plates sit on top of the floor and spread the bolt load over a larger area of the thin factory sheet metal. They use low-profile carriage bolts, which are kinder to the carpet than hex heads. Their slots let them work with several makes of frame rail brace.

The cross brace additions are a pair of cross braces that bolt to the frame rail braces for extra stiffness. They sit close to the chassis with clearance for most exhaust systems and hang no lower than the frame rail braces, so ground clearance stays the same.

Fits

• NA and NB Miata, 1990-2005

In the box

• Braces: pair of stainless frame rail braces with stainless bolts and lock nuts
• Backing plates: 4 stainless steel top plates (2 per rail), 24 M8 zinc carriage bolts, 24 M8 washers, 24 M8 stainless lock nuts
• Cross brace additions: 2 cross braces; they reuse the frame rail braces' own hardware

Good to know

• Fitting the braces means drilling through the car's floor.
• Running the backing plates with another make of brace? Ask us to confirm fit first.
• The cross brace additions need frame rail braces on the car or ordered with them (Braces Only or Braces + Backing Plates). Other makes of frame rail brace need the holes re-drilled to take them.

Import tariffs covered: the price includes the US import tariff, so there is nothing extra to pay on delivery.

Returns

• Returns are accepted within 30 days of delivery on new, uninstalled parts in their original packaging, less a 20% restocking fee.
• Return shipping is paid by the buyer, unless the return is due to our error, and the original shipping charge is not refunded.
• Installed or modified parts, electrical parts and made-to-order items cannot be returned.
• A part that arrives damaged, faulty or wrong: contact us within 7 days of delivery with photos of the part and the box.
• Contact us to start a return before sending anything back; returns ship to our shop, and we send the address.