EPA MPG without Hybrid Components?

i think you're pretty close. should be somewhere between corolla and camry.

 

It depends on how fast you drive it and how quickly you accelerate. The Atkinson Cycle engine is a low output high efficiency design so if you drove it gingerly then mpg would be in the 30s but if you demand a lot of acceleration power it could drop lower.

 

True but the effect is going to be amplified in the Prius because every other non-hybrid care uses an Otto Cycle engine which is more powerful. Thus when accelerating moderately you can stay within the efficient operating range of the engine. With a Atkinson engine you will very likely run it out of the efficient range and mpg will be much worse than a non-hybrid car of similar size and weight.

 

I hate guessing.

I would say in the 28-34mpg average range. That is about what people who lose their hybrid battery get. lol

 

It may not be able to complete the EPA test cycle without hybrid parts. In my youth, I drove a number of cars with 59 to 79 HP, about the time the EPA started testing cars they went away. Unlike the Prius, they really were scary to drive on freeways: they accelerated slowly, could not pull hills in top gear, you found yourself at 35 MPH but unable to shift to top gear, so the other cars are flying by 35 MPH faster than you. The 110 HP Gen 2 has none of these issues.

If it could pass the EPA test, then I expect 32/44 without regeneration and start/stop

 

That's a good point. In addition to excellent FE, the hybrid Prius systems provide torque needed for acceleration that would not, otherwise, be available from such a modest HP ICE. The drawback to this is the greater weight of the Prius, although the FE and torque of the Prius hybrid shows a net win. It seems that the current Prius would shed considerable weight and require a different ICE, to achieve maximum FE, if the other hybrid components were removed.

 

You are totally describing my 1988 CRX-HF. I hated having to merge on a freeway, when the ramp was going uphill (steep).

But I must say, driving my CRX to the Sierra Nevada Mountains (Lake Tahoe) taught me more about the importance of momentum than I ever learned in my 1968 Oldsmobile. It made me a much better driver.

 

The closest one would be 2012 Matrix 1.8L auto rated 28 MPG combined.

Prius has more cargo space and classified as midsize car instead of small station wagon.

 

If by "no hybrid technology' you mean going back to the Otto Cycle engine, I agree with usbseawolf2000. My assumption was that you kept the Atkinson Cycle engine, and Prius body shell, and just ditched the HSD. 0 to 60 would about double.

 

My Insight-I has a 67hp ICE and had no problem completing the EPA test cycle:
InsightCentral.net - Encyclopedia - Honda Insight Specifications
Of course it weighs only 1900 lbs, about 1100 lbs less than the Prius. It will do >100mph, and I don't have any problems with it on freeways.
Getting mpg from it is completely different from the Prius: one tries to keep its battery fully charged and use IMA boost as little as possible (most of the time I completely shut off assist). One uses lean burn and coasting (no burn) to gain mpg. But one still relies on the IMA battery for quick ICE restarts, autostop, engine balancing, electric steering, so deleting the hybrid system from it would cost mpg for it too.

Since the hybrid aspects of the Prius are so tightly packaged, maybe it would make more sense to ask what is the best EPA mpg rating one could expect if one replaced the entire HSD system with a conventional 110hp ICE with CVT.

 

But it does not only have a 67 HP ICE, it has IMA as well. My Mazda 808 Mizer station wagon had a 4 speed manual and an almost 1.3 liter engine.
Mazda Grand Familia - Wikipedia, the free encyclopedia
My later Mazda GLC station wagon had the same TC engine but with a 5 speed which helped a lot, even with 59 HP
Mazda Familia - Wikipedia, the free encyclopedia

 

As I said, "most of the time I completely shut off assist" (assist = IMA). That includes highway driving, onramps, etc. But in any case IMA adds only 6 HP, to 73hp total:
InsightCentral.net - Encyclopedia - Honda Insight Specifications
IMA has a bigger effect on the torque but as I said I block it (using MIMA) because ICE is adequate on its own for almost all situations.


Read more: http://priuschat.com/threads/epa-mpg-without-hybrid-components.110045/#ixzz1wZEiQlNb

 

In my previous commute, I rarely use more than 40 hp. Most of the time are under 30hp. That includes driving in the HOV lane at 65-70 mph.

That doesn't mean I don't use/need the full 110hp in my 2006 Prius. I have floored it in rare occasions.

 

The question is problematic from the start. Automatic transmission? Manual?
The problem begins with the -fact- that the current cars transmission wouldn't work without the "hybrid component". It continues with the -fact- that even if you substituted another transmission but kept the Atkinson cycle, you probably wouldn't be able to drive the car.
The Prius HSD, or more correctly the Toyota HSD -REQUIRES- all parts to be working properly and not substituted with something else to actually still propel the car down the road. Just ask someone who has had a full hybrid battery failure!

So we're back to -requiring- the engine to be re-done to Otto cycle and a "normal" transmission installed. A 3200 lb car with an 1800cc engine driven to the EPA cycle would probably get 30-35 MPG, given modern engine and transmission technology. The aerodynamics wouldn't have much effect on the EPA cycle.

There is Toyota documentation online which outlines the contribution in a percentage basis on the efficiency gains due to the HSD and each "part" of it. Such as regenerative braking, efficiency gains due to the Atkinson cycle, etc.
For example, the Atkinson cycle engine brings the engine from about 25% efficiency to about 35% efficiency. IF you could actually drive it, a car with that change alone would get about 20 to 30% better mileage.

 

New Subarus with CVT have about a 20% improvement compared to prior years, although some of that improvement is also from a smaller ICE.

 

In case anybody is going to make calculations, the 2012 Prius is 3042 lbs:
Toyota Prius - 2012 Performance & Specifications