lexicanto

The video is promotional and posted on Youtube by Lexus Europe, but it's very interesting.


John Goreham from Torquenews gives the credit, though, to BMW.


But he is "skeptical of any claim that a turbocharged four can match both the fuel economy and also power of a modern six cylinder engine. Regardless, the automotive world knows it can save a few pennies on each smaller motor it can convince buyers to take home and also gain a few tenths of a mile per gallon on the EPA estimated mileage cycle."

http://www.torquenews.com/1083/video...-engine-action

What about you? Are you optimistic or skeptical about the claim that a turbocharged four can match both the fuel economy and also power of a modern six cylinder engine?

Mr Bond

There has been test between the BMW 5 series 3.0 six cylinder (258 hp) versus the new 2.0 4 cyl that has 245 hp here in Europe. And yes, the 2.0 turbo wins in every aspect ( daily driving ) besides the sound and vibrations of course. But when it comes to hard driving (repeatedly full throttle accelerations and 100-130 mph on german Autobahn ) the turbo looses its fuel economy advantage and the difference between the old 3.0 is negligible. On the other hand, that kind of driving would send you to jail i many countries.

yowps3

The saving grace behind these new 2.0L engines is the use of balance shafts. Usually automakers don't use balance shafts for engines with less than 2200cc displacement..

But they are right about the modern six vs turbo four. I don't think these compromised 4-cyl turbos are as good as the modern 3.5L V6 you find these days.

Unless your talking about real uncompromised turbo cars like Evo & WRX etc as they're a different story..

lexicanto

I wonder why car companies go after and advertise these types of horse powers when you can't drive that in US roads.

IS350jet

Skeptical. I believe manufacturers should focus on the fuel efficiency of V6 engines. With the R&D dollars they're spending on high efficiency turbo fours, they could have had a 40 MPG V6 by now!

Sulu

Manufacturers could build smaller-displacement 6-cylinder engines but they would be more expensive to build than similar-sized 4-cylinders. The 6-cylinder has 50% more parts than the 4-cylinder engine.

yowps3

Yet the smaller 4-cyl Turbo's are heavier.

As Toyota claimed that this new 2.0T is heavier than the 2.5L 4GR-FSE V6

Whitigir

IS250 already has small V6 in it, and it sucks , reliability aside

Whitigir

It has to be, because of the Manifold, water cooled turbo housing, additional piping. This new I4 Turbo is no joke. Toyota had put a lot of Engineering in it, it is marvelous. It has Oil grooves in cylinder wall, additional oil squirts in the Top, and more than 1 million Km of severe stressing and testing for reliability.

I think this I4T will be super good for tuning. Take the TC 4 cylinders for example, the engine has additional oil squirts and it already pumped out 7 seconds TC in 1/4 miles.

This I4T is 2 steps ahead of the TC NA 4 cylinders. I wouldn't be surprised if it can pump to 1000 HP reliably. I would be very interested to see how the NX drive. If it is anything better than my STI, I would trade in in the next few years.

After all, nothing can take away my TOyota enthusiasm

JDR76

We already know they can be competitive in power and fuel economy.

But if the goal is only to match the power and fuel economy of a 6 cylinder, then what's the point? Why not stick with the 6 cylinder, with its refinement and reliability?

The goal of these new smaller turbo engines needs to be to match the power, refinement, and reliability of the modern V6/I6, while improving on fuel economy.

IS350jet

Yes, this appears to be true...........................for the manufacturer! To the end consumer, the turbo fours are just as expensive as the competing 6's. V6 Altima's, Accord's, and Camry's are within dollars of the turbo fours from Ford, Kia, and Hyundai, and the 4's don't have near the power, refinement, smoothness and quietness.
On top of all that, out in the wild, the 4's are not getting better fuel mileage than the 6's.

Sulu

Did not know that Toyota's new 2.0T is heavier than the 2.5L 4GR-FSE V6.

Is that not the whole purpose of these new turbo-4s -- power of a 6 but fuel economy of a 4?


It would be difficult to truly compare price of turbo-4 with equivalent 6, since they are either/or and no mass-market manufacturer (that I can think of) offers both a turbo-4 and a 6 in the same model line-up. Factors I can think of:

1. 6-cyl engines are offered as premium models in the line-up and turbo-4s are also offered as premium models.
2. 6-cyl engines currently offer economies of scale that newer turbo-4s do not yet offer (older, established technology with existing parts and components vs. newer technology with new, still more-expensive parts and components).

JDR76

Absolutely. That was my point. I was responding to the question in the original post of whether or not the turbo 4s could match the power and fuel efficiency of 6 cylinders. My response was intended to state that simply matching 6 cylinders would be of no benefit. The point of the turbo 4 is to improve fuel economy.

IS350jet

IMO, in order for a turbo 4 to to remain competitive with their 6 cylinder rivals, they would need to be as smooth or smoother, as powerful or more powerful, as fuel efficient or more fuel efficient, and cost significantly less. Otherwise, what's the purpose? Oh.......right............TUNERS!
Just give me the six any day.

spwolf

considering that this is replacing 2.5l V6 in Lexus lineup, it will easily be more fuel efficient while being faster.