Hoovey689

iTrader: (16)

And those new ones switch from Otto to Atkinson to Otto etc.. correct?

Sulu

Correct -- efficient Atkinson cycle at low load and more-powerful Otto cycle at high load.

webra

Part of the reason for going with higher stress on smaller engines is that for many countries cars are taxed on the cubic capacity of the engine. Not withstanding that, it appears Lexus, once the leader in hybrids, is in need of catching up. The Germans can now get same economy numbers and much better performance, without a cvt.

LexRuger

I've had a CT and ES hybrid loaner. They just weren't seamless enough. Not sure if I could enjoy a hybrid drivetrain. I drive cars like I stole em. Give me full electric or full gas.

Hoovey689

iTrader: (16)

Lexus does not use a CVT despite their 'eCVT' wordage. The transmission is a Power Split Device (PSD) that utilizes a dual planetary gear set. A little more advanced and refined than those traditional 'rubber band feeling' CVTs.

webra

Yes that is totally correct. And they proposed that this was the best way for efficiency. But now others can achieve the efficiency, with much more performance, without the rubber band effect, which the Lexus system still has it. Interesting also that while other car makers improve on performance as they move though generations, Lexus seems to do the opposite. Why?

Hoovey689

iTrader: (16)

'Opposite' would imply they are removing performance. I wouldn't say that, but rather their current powertrains have remained overall stagnant from said performance standpoint.

We're on the cusp of a new generation powertrains. Unfortunately the wait seems to be at a glacial pace

Sulu

That is well-known and well-accepted. But it is entirely possible to size your engine too small for the conditions, and if you do so, it will be in constant stress and an engine in constant, real-world stress is not going to give you the best fuel efficiency. BMW, by only providing a 2-litre 4-cylinder engine for this 7 Series hybrid, has very probably sized its engine too small for the size and weight of the car; the engine -- in real-life conditions -- will constantly be in boost.

The German hybrids may beat Toyota / Lexus hybrids in European official fuel efficiency test numbers but it is known that the European fuel efficiency is government-sanctioned lying. The lengths the manufacturers go to in order to get the highest numbers -- removing seats to save weight, taping over body seams to cut down on aerodynamic drag -- is laughable. No car in the real-world will get those test figures, but... I am willing to bet that Lexus hybrids get closer to its test numbers (and get better real-world fuel-consumption) than the Germans do.

Thanks for explaining!

chromedome

Actually, Lexus and Toyota hybrids get close to their manufacturer efficiency ratings while most European hybrids don't. The Euro MPGe test values should be taken with a few kilos of salt

In fact, any MPGe value should be considered pointless because it doesn't mirror real world driving. It's always disheartening to read about plugin hybrids like the X5e and XC90 T8 getting 20-ish mpg once the battery pack is depleted. The dirty secret about forced induction is that you get high mpg only when off boost and these heavy plugins have to run on boost to go anywhere.

webra

The 330e does look like it will get the numbers, both in economy and performance. It's as fast as a GS450h in acceleration.