[SGVLUG] Especially for Tom & his Prius....

[David Lawyer]

> > On Sun, Jul 09, 2006 at 10:07:06PM -0700, Dustin Laurence wrote:
> > > I found this screamingly funny:
> > > 
> > > http://youtube.com/watch?v=H_5VfwihIpo&search=top%20gear
> > 
> On Mon, Jul 10, 2006 at 04:31:40PM -0700, David Lawyer wrote:
> > I didn't find it funny at all.
> 
On Mon, Jul 10, 2006 at 04:49:35PM -0700, Dustin Laurence wrote:
> That's because you have some, ah...unique theories about cars.  Trust
> me, to the rest of the world, it's quite funny.

The engine performance curves are facts, not theories.  But they are
difficult to get: You need to either read Russian and have access to
literature not obtained by US libraries or know someone who worked on
research for an auto manufacturer.  Well, I think there are a few
exceptions to this.

If you operate a gasoline engine with wide open throttle, then the
pumping losses as low, just like a diesel.  That's why the thermal
efficiencies are about the same (in this operating mode).  One way
operate a gasoline otto engine like this is to coast (pulsing, etc.).
Another is to directly inject gasoline into the cylinders --injectors
on most cars now inject it into the intake ports of in intake
manifold.  But some directly inject it.  Another method to get wider
open throttle is to disable a few cylinders (GM) or uses stratified
charge to get a lean mixture to ignite.  Some cars now use this.

So there is in progress a convergence of gasoline and diesel engines
where the gasoline engine is becoming more like a diesel.

			David Lawyer