Consumer Reports: more drivel?

[ZDan]

Originally Posted by Ryephile

Here's what I meant to reference in saying you're off base:

totally stand by my remark.

"grossly overweight" is entirely relative. Modern crash standards are a significant reason cars have gained weight since the 80's.

No, I just proved otherwise. New car, same size and weight and relative cost and performance, SAME weight.

The rest of the weight comes from scaling the cars to an increasingly obese population and the significantly added feature content.

Replace "the rest of the weight" with "*all* of the weight" and add in much more powerful engines and bigger wheels/tires.

Cars like the twins are now a statistical outlier instead of average sized like the Silvia was.

Silvia wasn't "average" sized in 1989, it was pretty small then.

But of course today's cars have bulked up a LOT. Big dumb heavy people must have their big dumb heavy cars, so that's what appears on the market

Stick by the comment that had CAFE continued to go up every single year instead of holding pat at 1987 standards for about 2 decades, cars wouldn't have bulked up as much as they did, if at all.

[Ryephile]

Originally Posted by ZDan

...But of course today's cars have bulked up a LOT. Big dumb heavy people must have their big dumb heavy cars, so that's what appears on the market
....

This scaling is why the Twins are now considered small, despite being dimensionally on par, or even big compared to older & less safe models from years of yore. Like I said, it's all relative based on the context. If you need a good example of how times have changed, look at the evolution of the 911.

Nevertheless, does this excuse CR's propaganda publication?

[ZDan]

If CR have compelling scientific evidence, they should provide it.

I must confess to hoping that it's true that the smaller-displacement turbo 4s don't really get that much better fuel economy. I'd like for larger-displacement multi-cylinder n/a engines to survive!

It does make sense that a smaller engine off-boost should be operating more efficiently under cruise conditions than a larger-displacement n/a engine. But the turbo will suffer a tiny bit due to having to have a lower c.r.

[Ryephile]

Originally Posted by ZDan

If CR have compelling scientific evidence, they should provide it.

I must confess to hoping that it's true that the smaller-displacement turbo 4s don't really get that much better fuel economy. I'd like for larger-displacement multi-cylinder n/a engines to survive!

It does make sense that a smaller engine off-boost should be operating more efficiently under cruise conditions than a larger-displacement n/a engine. But the turbo will suffer a tiny bit due to having to have a lower c.r.

LOL, exactly! You know, scientific method and all. Alas, as I unfortunately always get to say: "don't let the truth get in the way of a good story."

That said, your preference for big n/a engines will always be around; they'll likely end up being niche markets [like American Muscle or super sports cars] more than mainstream powertrain choices.

The best current ICE solution is highly flexible cam phasing and lift where they can operate the engine in pseudo-Atkinson cycle and/or stratified or even HCCI during low load for maximum FE (low BSFC) and then also adjust to get peak torque [aka high BMEP] during high load requests. Remember that most boosted GDI engines nowadays are running over 10:1 static compression ratio, since mechanical quench is so well engineered. This keeps off-boost efficiency [as a general rule of thumb] higher than engines of a generation ago solely using port injection. What drags these engine solutions down are the high curb weights and high overall drag of modern [read: big] cars. Remember that aero drag = Cd x frontal area. Reduce frontal area and total drag plummets.