Atkinson engine without the motor assist?

Try driving ur Prii with 2 HV bars left.......this will give u an idea how it would feel.......it's pretty gutless.

Not sure if its been used without the electric motors.

 

...cause there's not a big market for a car that feels more gutless than a Mercedes 240d?

 

My rudimentary understanding of the Atkinson cycle engine is that it produces more efficient fuel economy at the cost of a loss of power density.

So it's great in a Hybrid that is being augmented by an electric motor.

But there is reason you don't see pure ICE vehicles with the Atkinson Cycle. To really be viable it needs augmentation for automotive use.

I mean in "Theory" you could tie horses to the front of the vehicle and turn it into a buggy. Doesn't mean anyone would want to do it.

If it was as simple as simply doing it? Yeah you'd see a lot of ICE Atkinson Cycle engines. The absence of this reality tells me it simply is not very viable.

 

The Mazda Milenia used a Miller cycle engine, which is just a Atkinson cycle engine with a Supercharger.

Mazda K engine - Wikipedia, the free encyclopedia

 

Yeah, but a supercharger is augmentation.

Has anyone ever "just used" an Atkinson Cycle engine without augmentation? Everything I read is that it simply does not create enough power density to be used as a stand alone power option in an automobile.

 

You don't understand fully. At 1200 RPM idle you -could- drive an Atkinson engine only car. But what would be the point? With a 1200 RPM idle it would get mediocre mileage. Oh, and make no mistake, it would be VERY gutless. With the Prius battery at min. you still get no idea how gutless, as you -still- get lots of assist.

Do you really want to have to get out and push to get it going?

People seem to think you can change the Prius system to "try out" various different things.
WRONG!
The Prius is designed as a system, and all parts have to work for the Prius to work.

 

I have driven cars with as little as 52 HP, they simply would not be marketable in today's car market.
0 to 60 in 17 seconds. Radio optional.

Popular Science - Google Books

 

It's all about the torque, that's why electric assist works so well with the Atkinson cycle engine, instant torque from the motor(s). Even "gutless" 3 cylinder engines have gobs of torque at low RPM when compared to an Atkinson cycle engine, so starting from a standing stop is still fairly acceptable with a "gutless" 3 cylinder Otto cycle engine, whereas an Atkinson cycle engine would take hours ( yes, I'm exaggerating) to get up to usable speeds from a standstill.

 

A Prius 1.8l Atkinson cycle has about the same torque as a 1.4-1.5L Otto cycle. The difference is greatly exaggerated in folklore.

 

Is the 1.5L in the Gen2 Prius an Atkinson ?

 

Yes.