why do you make that assumption?
Because it is a reasonable assumption, and I need to make it clear what assumptions I have made.
says who?
Science. Read reports by the ANL, or SAE papers, or one of the EPAs gigantic reports on gasoline engine technology.
what is 'better'?
I meant bigger
I think all your assumptions are fallacious
ICE engines run more efficiently when the throttle plate is open.
Engines run most efficiently at mid-high load, wide open throttle tends to be less efficient due to timing retarding, fuel enrichment.
grassrootsmotorsports:
Gasoline engines are more efficient at larger throttle openings, due to reduced pumping losses through the throttle plate. Also, higher RPMs result in more frictional losses inside the engine. OTOH, wide open throttle often puts the car into an open-loop mode and makes it run richer.
Im not disputing this, did you read or understand my original post? Also keep in mind you usually will get peak thermal efficiency in the range of 2000-3000 or so rpm at a mid-high load.
So, in general a larger throttle opening[to a point] means higher efficiency
There is virtually no small displacement engine that is less efficient[burns more fuel for a given power output] than a large engine.
This is complete and utter bullshit that demonstrates you lack an understanding of how these things work.
Then add the fact that you have to drag the weight of the engine around all the time even when it is not running
And the weight of the frame and suspension to support that larger engine
And that you could have more battery instead of dead engine weight
This is a silly argument that is often used against PHEVs, there is a VERY good reason why almost every plugin hybrid made isn't using a 2 cylinder motorcycle engine that barely meets the power requirements on a level road (looking at you, I3-REX).
It is marketing, 100 percent
The buyers they are after don't want no dang 4 cylinder engine, period
I don't think you understand that there are legitimate reasons why people want a more powerful engine, even in a plug-in hybrid.