Direct injection is still expensive but is a huge step forward when paired with turbos since there is no fuel in the combustion chamber to pre ignite. And it is even possible to utilize multiple injections per firing cycle to get the exact stratified mixture and pressure profile all throughout the piston excursion. But it is expensive, complex, and noisy. Mercedes is achieving 181 hp/ Liter with maximum pulse boost pressures of 1.8 bar/ 26 psi. With flat torque of 450nm/ 332 ftlb from 2250-5000. In a family car.
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Mercedes A 45 AMG: The most powerful 4-cylinder turbo engine in the world
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