Last post on Jun 17, 2008 at 5:30 AM
You are in the Toyota Sienna
What is this discussion about?
Toyota Sienna, Hybrid Cars, Van
#35 of 44 Re: I vote for the I4 hybrid but with a SuperCharger. [timothyh]
Apr 25, 2008 (7:10 pm)
CAFE uses unadjusted EPA fuel economy numbers.
They've been lowered twice, yet CAFE still uses the very outdated higher numbers from the 1980s.
The Sienna would probably get 23-24mpg on that old scale.
#36 of 44 Please; NO 4 cylinder engine for the Sienna
Apr 26, 2008 (5:50 am)
V-6's are rough enough, especially in 90 degree configuration and without counterbalancers. Coming from my last three cars with rotary, inline 6, and V-8 motors, the current Sienna motor doesn't feel particularly smooth to me. The last thing I'd want is a large unbalanced inline 4 booming away under the hood. Inline fours are not in primary balance, nor are 90 V-6's. The only way to get them to be truly smooth is use counterbalancers, which add weight and mechanical complexity. At least a decent V-6 is smoother than an inline 4.
#37 of 44 Re: Please; NO 4 cylinder engine for the Sienna [basenjiboy]
Apr 26, 2008 (8:28 am)
"The only way to get them to be truly smooth...."
Yes, that's likely very true for I4/inline, but what about "boxer" style..??
Wouldn't those be even more "perfectly" balanced vs any "V" engine..??
#38 of 44 Re: Please; NO 4 cylinder engine for the Sienna [basenjiboy]
Apr 26, 2008 (8:30 am)
There is negligible additional complexity in having twin counter rotating balance shafts to smooth out an inline 4-cyl. I know Chrysler used them on its now superceded 2.5L 4-cyl. I suppose that the European mfgrs use them on their 2.0 L 4-cylinder engines.
#39 of 44 Re: Please; NO 4 cylinder engine for the Sienna [basenjiboy]
Apr 26, 2008 (6:44 pm)
The chain-driven 2GR V6 isn't exactly known for being quiet. The 3MZ was actually more quiet.
It's worth the trade-off for all the extra horsepower, but still.
FWIW Toyota added sound insulation to the fire wall and along the door sills to offset the extra noise from the V6.
Hybrids often shave weight by removing sound deadening, though.
#41 of 44 Re: Paging wwest, paging wwest... [ateixeira]
May 13, 2008 (9:54 am)
#42 of 44 New Japan-only Toyota mini van drops hybrid
May 19, 2008 (12:05 pm)
Toyota introduced an updated version of its Japan-only minivan, the Alphard, last week. The Alphard did have a hybrid version from 2004-08. The 2009 drops the hybrid version. Toyota is introducing a V-4 and a V-6 version of the Alphard in Japan. The V-4 is said to get 27mpg. Does anyone know whether that's highway or combined?
Does any one know if this means no hybrid system for the Sienna?
#43 of 44 Future Sienna
Jun 17, 2008 (5:22 am)
When does the next generation Sienna come out? Just curious!!
#44 of 44 Re: Future Sienna [surjn98]
Jun 17, 2008 (5:30 am)
The speculation is 2010.