Collection: Rotary Collection

J-Spec Garage is your US headquarters for 13B rotary engine parts — and the only place in the country where you can buy genuine RaceOnly billet CNC rotary components. Whether you're working with a naturally-aspirated 13B from a Series 4–6 RX-7, a twin-turbocharged 13B-REW from the FD RX-7, or a bridgeported race engine, we carry the parts you need to build it right.

Our rotary catalog includes apex seals, side seals, e-shaft components, rotor housings, oil and coolant system parts, fuel system upgrades, and precision billet accessories. We stock components for every stage of build — from a daily-driven street rebuild to a high-horsepower track setup pushing well beyond 400 whp.

The 13B-REW rewards quality parts with reliability and performance. J-Spec Garage stocks direct, ships fast from the US, and backs every order with our price match guarantee. No other US retailer carries RaceOnly.

Shop 13B rotary engine parts below.

New to the rotary? Start with What Is the 13B-REW? The Mazda Rotary Engine Explained — how it works, what makes it unique, and what it takes to keep one reliable. Building a performance 13B-REW? Read the FD RX7 13B-REW Engine Parts Guide.