Aftermarket performance auto parts, parts designed to help you win

Parts designed to help you win.

High performance parts for Miatas, S2000s, BRZs and more!

New Arrivals!
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DEALER APPLICATION

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NA Miata performance parts

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NA Miata Parts
NB Miata Performance Parts

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NB Miata Parts

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About us

Find out about our company, our products and services, and contact information.

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Store

Want to purchase our products? Or just want to see what we offer? Visit our online store!

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Dealer Application

Do you have a retail company and interested in becoming an R Theory Dealer?

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Worldwide Shipping

We ship anywhere in the world! Visit this link for an International Shipping Quote.

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4 Reasons to Choose Us

Built by Car Enthusiasts

We care about your project car! If it’s not something we wouldn’t put on our own car, we won’t sell it.

International Shipping

No matter where in the world you are, we have shipping options to your door.

Wide Range of Products 

R Theory offers almost any part that you would need for your build. Check out our line up of R Theory Designed parts as well!

Customer Support

We are here to help before and after your purchase. With decades of combined experience, we will help to ensure everything goes smoothly.