Last post on May 07, 2009 at 7:11 AM
You are in the Hatchbacks - Archived Discussions
This discussion is ARCHIVED. To reactivate the discussion, post a request in the Lost? Ask the Hatchbacks Host for directions! discussion.
What is this discussion about?
Scion xB, Scion xD, Future Vehicle, Hatchback, Wagon, SUV
May 07, 2007 (11:03 pm)
With the new Dual VVT-i engine in the xD, when just considering the engine, you'll get better economy than the old 1.8 engine in the corolla. But having said that, their is more to mileage than just the engine. The body shape of the xD and the short gear ratios, scion has implemented to provide quick response, will have an overall effect on mpg. But this car is not just about good gas mileage for scion. Scions purpose is to introduce the toyota brand to people who would not other wise have purchased a toyota. They have been effective with this approach. But I feel the xD will provide very good mileage with this new engine despite its shape. This engine technology has been proven effective in other toyotas. Look at the toyota tundra. The 4.7 with Intake only VVT-i gets 15/18. The 5.7 with intake and exhaust VVT-i (like the xD motor) provides 100+ horses and gets 15/20. So there you have a motor giving more power and better mileage at the same time just like the xD compared to the xA will hopefully show. Only time will tell the true story but pound for pound, even with its draw backs, the scion xD is going to be a great little car that gives very good mileage. The honda fit second generation is not expected until some time in 2008 calendar year. I wish it would come sooner but its not going to happen. I'm going to be buying a xD this fall. Maybe in 5 years honda will have a couple of diesels for me to trade my little xD in for.
#60 of 356 Re: k [ohplezz]
May 08, 2007 (7:29 am)
The body shape of the xD and the short gear ratios, scion has implemented to provide quick response, will have an overall effect on mpg
this is what concerns me. the scion xa was slow anyway, so i felt it was overkill to have the engine revving so high at highway speeds (5 speed xa was booming so loudly on the highway that it became tedious on just a 10 minute test drive) were talkin 3600+ rpms at what should be a relaxing cruising speed of 70 mph. the corolla 5 speed is about 2850 at 70 mph. heck, even the yaris is relaxed at highway speed (about 3100 rpm)compared to the xa. 128 hp cars arent fast anyway, so i hope scion makes the xd a better highway cruiser(keeping the rpms around 3000 at 70 mph.this was the primary deal killer with the xa for me.
#61 of 356 Re: k [roxy84]
May 08, 2007 (8:18 am)
I have an 2006 xA automatic, and I don't agree with the numbers you quote about rpms vs speed. Here are the figures I have measured in fourth gear: 1750 rpm 40 mph, 2100 rpm 50 mph, 2500 rpm 60 mph, and 2900 rpm 70 mph. I don't find it too noisy at 70 mph, but the ride can be uncomfortably choppy at that speed on concrete highways with their expansion joints. On smooth asphalt it rides very nicely at that speed.
I also have a 2006 RAV4 V6 automatic that rides quietly and comfortably on the highway at 70 mph, so that's what I use on trips. However if the xD proves to be a good highway car, I plan to sell both of my cars and "step up" to the xD. I love the xA around LA where I do most of my driving, but I don't really want to own two cars.
#62 of 356 Re: k [jbrahms]
May 08, 2007 (9:21 am)
I have an 2006 xA automatic
yes, but i was referring to the 5 speed xa. id have given up some speed in the xa just to cruise at a resonable rpm at 70 mph. my 126 hp corolla is plenty fast( for my needs) with a manual transmission, and is decent with highway cruising. the honda fit manual has this problem as well at about 3400 rpm at 70 mph.
im just begging scion not to have such vastly different final gear ratios in the auto vs manual.
#63 of 356 Re: k [roxy84]
May 08, 2007 (10:07 am)
I would have thought the fifth gear in the manual transmission would run at a lower rpm than the fourth gear in the automatic at the same road speed. Isn't that the whole point of the fifth gear?
#64 of 356 Re: k [jbrahms]
May 08, 2007 (2:32 pm)
every econo car ive test driven in the past 5 years is the same in this regard. the auto tranny cruises at lower rpms on the highway than the 5 speed counterpart.
on cars like the xa, xb and fit, and many other econo cars, the difference is quite drastic. i disliked the manual fit's gearing at highway speeds so much that i crossed it off my list. the auto tranny was much more pleasant.i guess automakers think it gives more power under foot at that speed or the lower gearing makes it "sporty".xa, xb, yaris matrix, corolla, civic (non si), etc....all these econoboxes are slow and they should never be confused with sporty.
but i am a diehard stick driver, and will remain so until they quick making sticks or my left leg and/or right arm fall off.
i really hope the xd manual tranny is not so punishing to the driver at 70+ mph as the manaul xa/xb. its quite a bit larget engine, so im hoping they wont feel the need to gear it so short.
#65 of 356 Re: k [roxy84]
May 08, 2007 (3:01 pm)
Apparently the fifth gear in a manual tranny is not really an overdrive gear in the subcompacts you mention. I'm surprised to hear that because the EPA gas mileage is always reported better in the manual than the automatic, even under the 2008 measurement system. I guess the energy losses in auto tranny (in the form of heat) must be pretty significant.
#66 of 356 Re: k [jbrahms]
May 08, 2007 (3:46 pm)
I would not say that heat losses are the cause for autos poor mileage. A 4 speed auto tranny just does not have enough gears to provide great mpg. It is often left in to high or to low a gear for good fuel economy. Also with manual trannys a 6 speed gives you greater mileage than a 5 speed because the 6th gear is very tall for relative low rpm at hway speeds. For those of you who do a lot of hway driving, and are concerned about high rpm noise, you should get the auto xD. The 5 speed will probably be reving pretty high at 80 mph. I love to drive and that means I've got to buy a 5 speed. Fuel economy and driving pleasue beat out the high speed rpm noise in my book. Don't forget that gas will be over 4 bucks a gallon this summer!
#67 of 356 Re: k [ohplezz]
May 08, 2007 (5:32 pm)
Also with manual trannys a 6 speed gives you greater mileage than a 5 speed because the 6th gear is very tall for relative low rpm at hway speeds.
ideally, but this often is not true. many 6 speed trannys simply make the 6th gear what the 5th would have been and make all the other gears shorter. the nissan versa 6 speed manual is a good example. at 70 mph in 6th gear its rpms are at 3100. this is not as low as id hope with a 6 speed.
i still contend if the corolla 5 speed cruises at 75 mph at 3000 rpm, a similar sized engine in the xd should be just as relaxed. the gearing in the corolla, to me, is not too long or short. it allows me to push when it need acceleration(0-60 times are quite respectable with a 5 speed corolla) and cruises at relaxed enough engine speed to give me consistent 40+ mpg on the highway. the only handicap the xd should have compared to the corolla are the aerodynamics.
#68 of 356 high revs in high gears
May 10, 2007 (11:11 am)
i thought the axle ratio has as much to do with how fast an engine revs as the transmission gearing does?