GENUINE MAZDA OEM Exhaust Header Gasket for Mazda RX8 (Series 1 & 2, 2003-2012)

Part details

The RX8 exhaust header gasket is the critical sealing layer between the rotary engine's exhaust ports and the header or manifold. Fitting a new one is non-negotiable any time the original exhaust is removed. This genuine Mazda part is manufactured to exactly the same specification as the gasket fitted at the factory. It covers both Series 1 and Series 2 Renesis engines. Reusing an old, compressed gasket during an aftermarket exhaust installation is one of the most common causes of post-install exhaust leaks. A new OEM gasket eliminates that risk entirely. RX8 Exhaust Header Gasket, Genuine OEM Features Factory-spec sealing geometry matches the Renesis exhaust port shape precisely, providing a flush, leak-proof mating surface from the first start. Also, it is made from genuine Mazda materials engineered to withstand the rotary engine's characteristically high exhaust temperatures and sustained high-rpm operation. Fitment covers both Series 1 (2003-2008) and Series 2 (2009-2012) RX8 models, so it pairs directly with any header or aftermarket exhaust designed for the Renesis. A new OEM gasket arrives in known, uncompressed condition. Because of this, it re-seals more reliably than a reused original that has already conformed under heat and pressure. Finally, sourcing genuine Mazda exhaust components now is worthwhile. As production winds down, OEM sealing parts like this header gasket become progressively harder to find through authorised channels. For RX8 enthusiasts fitting an aftermarket exhaust or cat-back system, the difference this header gasket makes is felt on the very first idle. No exhaust tick, no seeping gases. The result is confidence that the new system is sealed correctly. A leaking header joint on a rotary engine not only sounds rough but can also compromise sensor readings and tuning accuracy. Therefore, getting the base seal right matters far beyond comfort. This gasket pairs naturally with the HKS Hi-Power Cat-Back Exhaust with Titanium Tip , where a fresh OEM header seal ensures the new system performs exactly as intended from day one, and with the APEXi High-flow Catalyser , since any cat or manifold swap requires the upstream header gasket to be renewed at the same time. For more information on genuine Mazda parts and their specifications, visit the official Mazda Australia website .

Listed fitment

Model

Series 1 (2003-2008)

Model

Series 2 (2009-2012)

Part information

SKU

OM-EHG-S1S2

Brand

GENUINE MAZDA OEM

Do I need a new exhaust header gasket every time I remove the exhaust on my RX8?

Yes. Once an exhaust header gasket has been compressed and conformed to the mating surfaces, disturbing it breaks that seal. Reusing the original is one of the most common causes of post-install exhaust leaks on the RX8, so fitting a new gasket every time the exhaust or manifold is removed is strongly recommended.

Will this gasket fit my RX8 if I'm installing an aftermarket exhaust or manifold?

Yes. The genuine Mazda exhaust header gasket fits both Series 1 (2003-2008) and Series 2 (2009-2012) RX8 models, and its factory-spec port geometry matches the Renesis exhaust ports precisely. It pairs directly with any aftermarket header or exhaust system designed for the Renesis engine.

What happens if I skip replacing the header gasket when fitting an aftermarket exhaust?

A reused gasket that has already conformed under heat and pressure may not re-seal reliably, leading to exhaust leaks at the header joint. On the RX8's rotary engine, a leaking header joint not only produces an audible tick but can skew oxygen sensor readings and compromise tuning accuracy.

Is a genuine OEM gasket better than an aftermarket replacement for the RX8?

The genuine Mazda gasket is manufactured to the same specification as the part fitted at the factory, using materials engineered for the Renesis engine's characteristically high exhaust temperatures and sustained high-rpm operation. It arrives in known, uncompressed condition, which an aftermarket equivalent from an unknown source may not guarantee.

Does this gasket suit both the Series 1 and Series 2 RX8?

Yes. This genuine Mazda exhaust header gasket covers both the Series 1 Renesis (2003-2008) and the Series 2 Renesis (2009-2012), so there is no need to source a different part based on your build year.

Should I replace the header gasket at the same time as fitting a high-flow cat or cat-back system?

Yes. Any time a catalytic converter, manifold, or cat-back system is removed and refitted, the upstream header gasket should be renewed at the same time. Doing both in a single job ensures the entire exhaust path is sealed correctly and avoids having to revisit the header joint later.

Are genuine Mazda exhaust gaskets for the RX8 getting harder to find?

OEM sealing parts for the RX8 are becoming progressively harder to source through authorised channels as production winds down. Securing a genuine Mazda exhaust header gasket now means you have the correct part on hand for your next exhaust or manifold installation.