Here's why:
* Rotary engine specifics: The 13B is a rotary engine, which operates differently than a piston engine. It generates more heat and experiences higher RPMs.
* High-performance demands: The 13B is known for its performance and high RPM capabilities. It requires an oil that can handle the extreme conditions.
* Shear stability: Synthetic oils offer superior shear stability compared to conventional oils. This means they won't break down as easily under high RPM and high temperatures.
* Viscosity: The recommended viscosity for most 13B RX-7s is 5W-30 or 10W-30.
Here are some additional recommendations:
* API certification: Look for an oil with an API certification (American Petroleum Institute) that meets or exceeds the requirements for your engine. This is usually indicated on the oil container.
* Manufacturer recommendations: Check your owner's manual for specific oil recommendations from Mazda for your model year.
* Additives: Consider using an oil with additional additives that help protect rotary engines, such as friction modifiers and anti-wear agents.
Note: It's important to use the correct type and viscosity of oil. Using the wrong oil can lead to engine damage.
