Are gas engines ever going to catch up?

Turtle n Peeps wrote:

Wes wrote:
Turbo'd engines of any fuel are more efficient than naturally aspirated counterparts.

You keep on saying this but it still is not true. BSFC is ALWAYS higher in a blown engine. It takes energy to compress air and that energy comes from the fuel.

I have challenged you before to produce a link that proves your contention that a turbocharged engine is more efficient but I'm still waiting for that link.

I'm hoping in a month or two I will dyno my personal blown engine and I will post the BSFC for you and others to see. I'm still debating whether to dyno or not.

About the 14 to 1 engine. Power and mileage is not linear with compression. IOW's you will get quite a bit of power and mileage gain going from 8 to 1 to 10 to 1. Smaller from 10 to 1 to 13 to 1. Above 13 to 1 very, very little gain for a gasoline engine.

Turtle,

You are quite right that turbo-charging does not automatically mean fuel efficiency. And you are correct that it has often meant quite the opposite in the past. However turbo-charging does not have to be less efficient. BSFC is not ALWAYS higher in a blown engine. The fuel per rpm will always be higher, but not necessarily the fuel per HP.

Tutle, here is a fairly detailed link for you:
http://www.autospeed.com/cms/article.html?&title=Turbod-for-Fuel-Economy&A=109931 .
Does it make more sense when it is better explained?

But we shouldn't really need a link, and of course a link can always be wrong too. But the "Thermal Efficiency" principle is logical when one thinks about how heat engines have to work. I have seen the increased thermal efficiency of turbochargers documented otherwise also, but I think it was in an unlinkable book on the merits of turbo-charging vs super-charging. I imagine more than a few of you have the same trouble, trying to remember where in the heck you saw something.

Wes
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