I've never ever heard of somebody clearing the 30mpg mark on the highway in a GS... of course I don't think I've ever heard of somebody just cruising at 55mph.

Is that actual measured at the pump or from the info center on the nav screen?

 

I think what Lexus effectively did with the IS250 was give us a 4 cylinder in 6 cylinder disguise. If you compare gas mileage with the Acura TSX:

1.) Acura TSX- 2.4L I4- 21 city/30 highway
2.) Lexus IS250- 2.5L V6- 21city/29 highway

Both have similar power ratings. Of course architecture is vastly different, but the small 2.5L V6 (combined with the 6AT) has the economy of the 4 cylinder of near same size. Everyone wins here, besides the DIY mechanic as mmarshall has pointed out with access issues. You also get to sell your car without risking the "Oh, its just a 4cylinder" stigma.

One thing that is very important to me is the sound of the engine. To me, a good V6 sounds much more smooth and refined than any 4 cylinder I've heard (although I have to say the Honda 2.4L is probably the most refined sounding out of 4 cylinder engines). You don't want an unrefined sounding engine in a luxury car.

 

Measured at the pump with miles divided by gallons of gas put back into the tank at fillup.

at 65 i'm seeing 30-31mpg
at 75 i'm seeing 27mpg

All taken on 100% gasoline blends, with the cruise control going.

 

Yeah I think you may be right. However, I am surprised that BMW doesn't use its 2.5L all that much anymore. However, having 2 extra cylinders does add weight.

I also don't know if I agree with your theory about engine sound. I think its true to an extent that 6 cylinders sound better than most 4 cylinder engines. However, comparing the throaty roar of my 2.5L boxer, well I find it much more appetizing than the 3.3L in the RX400h or even the dull (but powerful) 2.7L T that Audi used to use. I may be biased, but I think the engine setup, exhaust, intake, power output all affect whether or not your 4 cylinder produces a nice sound. Obviously, the 1.8L in the Corolla is going to be outshined by a 3.0L BMW.

Where do you get 100% gas anymore?

 

SLegacy, I know sound can be a very subjective and biased thing. I forgot about Boxer engines... I place them in a different category as they have such a very unique sound.

There is also a difference between the 6's. For the most part, I think domestic V6's sound very "choppy." I remember riding in a Jaguar S-Type 3.0 and thinking this sounds EXACTLY like the Ford Windstar my mom used to drive. I think many of the Japanese and European V6's just have a smoother sound. Perhaps its the timing, materials, and firing order used? I6's by nature of their architecture are very smooth motors, second only to a V12. I absolutely love hearing a 330 or IS300 romp by me.

Also, very good point about the extra weight. I didn't think about that one.

 

When i travel out of the emissions counties.

 

Of a somewhat related note.... a 0-80 video I made of a 328i loaner car I had a couple weeks ago. Nice exhaust note for a non turbo 3.0 I6.
http://www.youtube.com/watch?v=50VeH6z1-sk

Only reason I made an acceleration video of a loaner car before my actual own car is I was motivated to get the video taken and done with while I still had the loaner car. I don't have that same pressure with my car since I have it full time, but regardless I still plan to get a comparison video on the same stretch of road fairly soon here.

 

I'm on a laptop so I can't really compare the sound of the 328 to my dad's 330. I will say that it does look like that car accelerates better than the automatic 330xi we drove. It revved way up and somehow no power got to the wheels Definately a backwards AWD system.

Most dissapointing this about the 330xi's sound is that perhaps there is too much sound deadening material and the engine is always very quiet, even when you push it a bit.

 

Exactly, this is signature worthy!

 

Given the fact that most luxury cars have so much sound dampening and so quiet exhausts systems with 2-3 mufflers, I highly doubt engine natural engine sound or exhaust sound will make little difference. Personally, I can barely even here the engine or exhausts on most luxury cars. They are too damn quite.

 

The Altezza was available with a 3SGE four and I believe that was the sportier variant. I don't think it would have hurt the IS300 line to have had a 6-speed manual 200hp 4 cylinder.

Given what the IS is like today I think a four cylinder would be perfect as long as they give it a small turbocharger. Keeping an available manual transmission would be nice too. That's a hell of a lot more important to me than whether or not their cars are 4/6/8 or hybrid-electric powered.

But sure, bring on an IS with a high output, sporty four cylinder with 250+ horsepower. It should be faster than the 6-speed manual IS250 though. 0-60 in 6.8 or faster at least.

 

I don't think seeing a 4cyl Lexus would be out of the question. It's already evident they are using 4 cyl with hybrid with their newest high efficiency hybrid offerings. With the rising price of gas and the push toward more fuel efficient cars, having a 4cyl version of lets say the ES or a CT with an N/A 4cyl or turbo 4cyl wouldn't be a bad idea.

 

mb and bmw are moving towards turboed 4 cyl DI so I can see this being possible in the future.

 

audi, bmw and mb have huge lineup of 4cly in europe... i dont see why Toyota wouldnt.

I know Slegacy would buy one if it had tripple-DI, tripple-VVTI, twin turbo with SC.

:-)