Yamaha is proud to introduce its line of High Pressure Direct Injection (HPDI) outboards. Our HPDI outboards are geared to both the freshwater fiend and the saltwater savvy.
This revolutionary new design reduces exhaust emissions more than ever before, while also providing a more powerful, fuel-efficient solution to the conventional direct injection model. Furthermore, Yamaha's HPDI meets the rigid 2006 emission standards and while doing so, provides a quieter, more pleasurable experience!
In conventional engines, the fuel/oil charge comes up from the bottom of the piston. As the piston moves up to the top of the cylinder, combustion takes place. However, some of the mixture inevitably escapes through the partially open exhaust port. The spark plug can only fire after the piston completely covers the exhaust port and as a result, some of the fuel efficiency is lost.
With Yamaha's HPDI, the engine is designed to wait until the exhaust port is closed before the fuel is directed down the cylinder head. This means that you achieve maximum power and increased fuel efficiency.
- High pressure - HPDI creates better consumption of the fuel charge, dispersing it evenly and deeper into the cylinder head for improved combustion and lubrication.
- New engine design - Combustion chamber design enables fuel efficiency at all rpm ranges, with an emphasis on 2,500+ rpm range, where fuel economy is more important.
- Efficient combustion - Most other direct injection systems protrude into the combustion chamber, causing a disruption in the flow of fuel. By contrast, Yamaha's HPDI injectors stay out of the combustion chamber, which means a steady, uninterrupted supply of fuel, as well as better consumption efficiency. This also translates to less carbon buildup, increased durability, and less maintenance for your engine.
- Patented O2 Sensor - Yamaha is the only outboard manufacturer using a closed-loop system with a patented O2 Sensor that measures the oxygen content of the exhaust gases. The engine automatically adjusts the fuel supply to each individual cylinder to maximize power and fuel economy.
