To handle our plans for increased power, we ditch the weak and heavy OEM “Power Plant Frame” (PPF) in favor of a traditional transmission mount from Banzai Racing and differential brace from Sikky Manufacturing.
Mazda uses a giant, heavy beam they call a “Power Plant Frame” (PPF) to connect the engine, transmission and differential. This keeps the entire drivetrain as one separate structure that is supported just by the engine and differential mounts. This design was used on everything from the original MX5 Miata to current, the FD RX-7 and the RX-8.
However, with increased power or stress from wider and stickier tires, the stock PPF is prone to cracking. The solution is to remove the PPF and replace them with traditional transmission and differential mounts.
We sourced the transmission mounts from Banzai Racing, which is laser cut from ¼” steel plate and features Energy Suspension’s patented interlocking 70S durometer urethane mount to control movement of the transmission without adding NVH.
The heavy-duty rear diff brace is from Sikky Manufacturing and supports the front of the diff by connecting and spreading the load across 8 factory bolts in the chassis of the car. A small, hard durometer front bushing is used to reduce NVH compared to solid-mounting the front of the differential.