|
I've always thought the reason that, in this application, direct injection makes it more complicated to turbocharge or superchage the engine is due to the naturally high compression ratio. DI is what allows you to raise compression, which in turn makes it harder to FI simply due to the higher propensity for knock. In addition, I believe the piston dome governs the specifics of direct injection spray patterns (or something like that), but a high compression engine will need low compression pistons in a FI setup to keep it from blowing. Thus, arises additional complexity from having to design a piston that lowers compression, but retains the correct spray properties.
|