8valve

8valve refers to an internal combustion engine configuration that features two valves per cylinder. Typically, this includes one intake valve and one exhaust valve. This design is a fundamental and historically significant engine layout.

The 8valve engine is characterized by its simplicity and robustness. Compared to more complex multi-valve designs (such as 16-valve or 32-valve engines), 8-valve engines generally have fewer moving parts, which can lead to lower manufacturing costs and potentially greater long-term reliability. The valve train is often simpler, involving fewer camshafts and smaller valve sizes.

In terms of performance, 8-valve engines are generally considered less efficient in terms of airflow and combustion at higher engine speeds than their multi-valve counterparts. The smaller valve area limits the amount of air-fuel mixture that can enter the cylinder and the volume of exhaust gases that can exit. This often translates to lower peak power output and less effective performance in the upper RPM range. However, they can offer good low-end torque and fuel efficiency in certain applications.

Historically, the 8-valve configuration was dominant in automotive applications for decades. As engine technology advanced, particularly with the rise of performance-oriented vehicles and stricter emissions standards, multi-valve designs became more prevalent. Despite this, 8-valve engines remain in use today, particularly in smaller displacement engines, motorcycles, and in applications where simplicity and cost-effectiveness are prioritized over maximum performance.