Ram Air?

[Begle1]

I want to think about how the turbocharger responds to ram air effect.

Seems to me that a turbocharger "connects" the exhaust and intake pressures of an engine; if the air on the intake side is compressed to 5-10 PSI, the compressor turbine is going to need more energy to spin in that environment. The compressor gets that energy from the exhaust turbine; if the compressor has to work harder putting air in the engine, the exhaust is going to have to work harder leaving the engine.

The equation is not a simple one; you have valve over lap, fuel injections, turbo geometry, and intake and exhaust temperatures to consider. But I would think that the turbocharger reduces the effectiveness of ram air. I have the hunch that their are definite benefits to be had with ram air, but I think those benefits are far outweighed by the cool air scoops would allow you to utilize.

[JimmieD]

I don't think there's all that much to it. Air in-air out. The exhaust gases spin the turbine wheel which spins the compressor wheel. The air in is compressed by the compressor wheel. With some ram effect applied to the air inlet the turbo doesn't have to work quite as hard compressing it.

I wouldn't be expecting a tire smoking, grab another gear, "Whoa, hold on, baby!" explosion of excitement, but maybe a little easier job for the turbo to do. just like was said about rolling down the window and holding a cook pot outside, something's gotta happen.

I don't think it could have any effect on valve over lap, fuel injections, or turbo geometry, but intake and exhaust temperatures might be slightly lowered, maybe....