Fuel economy announced for the new Lexus IS250/IS350 - interesting results
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Fuel economy announced for the new Lexus IS250/IS350 - interesting results
Normally I wouldn't bother to post this, especially since it's not really noteworthy (not overly impressive or overly unimpressive gas milage figures)
But I guess we're finally in a day and age where an automatic transmission gets better gas milage?
The IS250 6-speed automatic gets 24/32 whereas the IS250 6-speed manual gets 20/29. I'm not sure what the ratios are but they're supposed to be pretty similar between the two - the manual is definitely not any more agressive in gear ratios than the automatic. I'm sure the parasitic driveline power loss on the auto is still worse than on the manual. So how is the auto able to get better milage? Just more intelligent shifting?
If you were trying to get the manual for cost savings (by not checking it off on the options list), in the end it would hurt you more than help you due to lost gas milage.
But I guess we're finally in a day and age where an automatic transmission gets better gas milage?
The IS250 6-speed automatic gets 24/32 whereas the IS250 6-speed manual gets 20/29. I'm not sure what the ratios are but they're supposed to be pretty similar between the two - the manual is definitely not any more agressive in gear ratios than the automatic. I'm sure the parasitic driveline power loss on the auto is still worse than on the manual. So how is the auto able to get better milage? Just more intelligent shifting?
If you were trying to get the manual for cost savings (by not checking it off on the options list), in the end it would hurt you more than help you due to lost gas milage.
An all-new six-speed sequential automatic transmission is partnered with either a 2.5-liter or 3.5-liter V6 engine. The new automatic transmission features a Formula One inspired, steering-wheel-mounted paddle-shift system for more spirited driving. The IS 250 rear-wheel drive earned an estimated combined fuel rating of 27 mpg (24 mpg city/32 mpg highway). The IS 250 all-wheel drive has an estimated combined fuel rating of 25 mph (22 mpg city/28 mpg highway). The high-performance 306-hp IS 350 realized an estimated 24 mpg combined fuel-mileage rating (21 mpg city/28 mpg highway). The IS 250 rear-wheel drive with a six-speed manual transmission has an estimated combined fuel rating of 23 mpg (20 mpg city/29 mpg highway).
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Re: Fuel economy announced for the new Lexus IS250/IS350 - interesting results
Maybe the source just made a typo, those numbers are off quite a bit for the same vehicle but different trans. options.
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Re: Fuel economy announced for the new Lexus IS250/IS350 - interesting results
Hmm... welll I thought I remembered hearing that they were similar ratios but it seems there's a noticable difference. There's even some changes for the AWD and IS350 model's automatics, too.
While the manual IS250's gear ratios are still shorter than the automatics, you still have to take into consideration that the manual has a taller rear end ratio, effetively making the individual gear ratios taller than they seem at first glance.
http://www.clublexus.com/gallery/dat...IS_Specs_2.JPG
While the manual IS250's gear ratios are still shorter than the automatics, you still have to take into consideration that the manual has a taller rear end ratio, effetively making the individual gear ratios taller than they seem at first glance.
http://www.clublexus.com/gallery/dat...IS_Specs_2.JPG
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Re: Fuel economy announced for the new Lexus IS250/IS350 - interesting results
No. By my calculations the final drive in 6th gear of the manual is 2.929 versus 2.275 for the automatic, that is if the specs at club Lexus are correct.
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Re: Fuel economy announced for the new Lexus IS250/IS350 - interesting results
Originally Posted by HAZ-Matt
No. By my calculations the final drive in 6th gear of the manual is 2.929 versus 2.275 for the automatic, that is if the specs at club Lexus are correct.
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Re: Fuel economy announced for the new Lexus IS250/IS350 - interesting results
Originally Posted by Threxx
No, what? That's what I was saying. The final drive for the manual is shorter and thus less fuel efficient.
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Re: Fuel economy announced for the new Lexus IS250/IS350 - interesting results
Pretty good numbers for the IS350. 21city and 28hwy from a 306hp automatic sports sedan is pretty damn good.
Another impressive thing about the IS350...it'll turn 13.7's 1/4 miles and 5.1sec 0-60's. I seriously wasn't expecting that.
Another impressive thing about the IS350...it'll turn 13.7's 1/4 miles and 5.1sec 0-60's. I seriously wasn't expecting that.
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Re: Fuel economy announced for the new Lexus IS250/IS350 - interesting results
Originally Posted by Gold_Rush
Pretty good numbers for the IS350. 21city and 28hwy from a 306hp automatic sports sedan is pretty damn good.
Another impressive thing about the IS350...it'll turn 13.7's 1/4 miles and 5.1sec 0-60's. I seriously wasn't expecting that.
Another impressive thing about the IS350...it'll turn 13.7's 1/4 miles and 5.1sec 0-60's. I seriously wasn't expecting that.
The IS460/IS500 (4.6 or 5.0L V8 from the new upcoming LS460) is supposed to have ~400hp so I would be suprised if you don't see high 12s possible from that thing.
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