07-15-2008, 08:17 AM
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#21 (permalink)
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Boxhead
Join Date: May 2008
Location: Fredonia, NY
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Quote:
Originally Posted by NeilBlanchard
Hello,
The two things working against the xB vs the Echo, is gearing (at highway speeds, the revs are high, right?) and the aerodynamics are probably the most important thing by far. Compare my xA to the Echo, and the largest difference is probably gearing -- my best MPG is 46.69 -- and that is with some aero mods...
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You're completely right. The Echo has significantly taller gears. It can probably get away with such due to being smaller, lighter, and having a more slippery shape.
The xB and xA are geared awfully short. The small upside to this is that we can do 30mph in fifth gear without lugging.
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07-15-2008, 10:59 AM
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#22 (permalink)
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Administrator
Join Date: Dec 2007
Location: Germantown, WI
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Theres a guy on cmpg with an echo hitting numbers in the mid to high 50s and recently had a 60 mpg tank. Its a very nice car.
Some aero info.
Echo:
Cd - .29
CdA - 6.57
xA:
Cd - .31
CdA - 7.26
xB (1st gen):
Cd - .35
CdA - 8.77
xB (2nd gen):
Cd - .32
CdA - 8.37
Yaris:
Cd - .29
CdA - 6.36
FYI, I made a list of many other cars here:
http://ecomodder.com/forum/showthrea...list-1935.html
Last edited by Daox; 07-15-2008 at 01:08 PM..
Reason: Correction
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07-15-2008, 11:13 AM
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#23 (permalink)
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Hypermiler
Join Date: Dec 2007
Location: Texas
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What are the gear ratios? RPM in top gear at 60mph, for example.
I know mine is a Honda, but I have no doubt I could beat 40 in an Xb. I don't do steady speed. That gives me mileage in the 40's, which is not good enough for me. I pulse and glide. That helps overcome the bad gear ratios.
Over at CleanMPG, there are three members with averages over 40 in Xb's. Two of them are 43, and one is 40.x.
update: found the specs and calculated 3000rpm at 60mph. My civic runs 2750 at 60. 63mpg*(2750/3000) = 57.7 mpg.
another update: my civic has a Cd of .34, CdA 7.20. 57.7 mpg*(7.2/8.77) = 47.4 mpg, counting for both gearing and aerodynamics.
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11-mile commute: 100 mpg - - - Tank: 90.2 mpg / 1191 miles
Last edited by PaleMelanesian; 07-15-2008 at 11:59 AM..
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07-15-2008, 12:14 PM
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#24 (permalink)
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Box Dreamer
Join Date: Jul 2008
Location: Pittsburg, CA
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My xB runs on 5th gear @ 3000rpm in 60mph. (See the tach by sight, I don't have scangauge)
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07-15-2008, 12:31 PM
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#25 (permalink)
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Mr. Blue Tape
Join Date: Jun 2008
Location: Fresno, CA
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Quote:
Originally Posted by Daox
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YES!!!! XA INFO!!!! But from your link, the xA has a CdA = 7.26 with a frontal area of 23.4. I'm not sure where your 7.40 came from.
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My 5 pillars of fuel efficiency:- driving style
- aerodynamics
- tires
- weight reduction
- engine maintenance
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07-15-2008, 01:08 PM
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#26 (permalink)
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Administrator
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That would just be me reading the chart wrong haha. I'll fix my post. Thanks for pointing that out.
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07-15-2008, 01:22 PM
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#27 (permalink)
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Box Dreamer
Join Date: Jul 2008
Location: Pittsburg, CA
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Thanks for the list. Now, I know why Insight and CRX saves that much gas. At least, they can P & G much longer distance than my xB.
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07-15-2008, 03:17 PM
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#28 (permalink)
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Mr. Blue Tape
Join Date: Jun 2008
Location: Fresno, CA
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I bet with some serious mods like adding a curved shield (optimized curvature) over the hood and windshield, grille blocks, wiper dam, front dam, side fairings for the wheels, removing the passenger side mirror, rounding out all the corners, belly pan, rear skirts, dumping the rear and passenger seats, yanking the radio/CD player/speakers/AC and attaching a boattail you will have dramatically better higher-speed mileage. It'll look something like the aerocivic... but taller.
But the aero should be better than the stock xB at the very least.
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My 5 pillars of fuel efficiency:- driving style
- aerodynamics
- tires
- weight reduction
- engine maintenance
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07-15-2008, 05:36 PM
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#29 (permalink)
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Box Dreamer
Join Date: Jul 2008
Location: Pittsburg, CA
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Not only taller, but also much longer by adding the nose and tail.... Hey, that doesn't look like a box anymore. It looks like a Superbowl.
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07-15-2008, 06:45 PM
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#30 (permalink)
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Rapidly Evolving Driver
Join Date: Jun 2008
Location: SF Bay Area
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I was about to post my latest tank (only need to fill up once a month, I bike to work and use the motorcycle when I can) when I saw this. I just got 37.7mpg on a 352 mile tank, but have gotten as much as 49 on a trip when I had the wind at my back and left very early in the morning which was all highway miles, no stop & go for about 200 miles. If you're ever in the Oakland/Berkeley area I can take you for a ride to see if I do anything different than you. Here's my mods:
-Lowered 1.75". This should help quite a bit, but I can't give you a mileage quote before the mod. This means the roof is 1.75" lower, but also that there is 1.75" less air going under the car where it is more turbulent, so I am sure it helps. Eibach springs.
-cold air intake, magnaflow exhaust. This should actually HURT mpg, so you could do better than I. Although, if I use the 1/2 to 3/4 throttle opening when I am accelerating, it may actually help. Who knows.
-original tires, 48psi, all extras taken out of the car, recent oil change, 175 lb. driver, drive until the warning light goes on, Costco 87 octane gas - random details.
-lots of pulse and glide, some drafting combined with pulse and glide (I do not like to tailgate for any length of time) some EOC coming down hills and some offramps
As always, be SAFE! But those are my tricks to get *close* to 40 on average between local city driving (under 40) and long distance driving. (over 40)
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