Gas Mileage with 2 identical drivetrains but 2 different drag coefficient - Fuelly Forums

Android Users - Coming Soon! - Migrating from aCar 4.8 to 5.0

Go Back   Fuelly Forums > Fuel Talk > General Fuel Topics
Search Today's Posts Mark Forums Read Click Here to Login
Reply
 
Thread Tools Display Modes
 
Old 06-30-2013, 08:47 PM   #1
Registered Member
 
Join Date: Apr 2007
Posts: 57
Country: United States
Gas Mileage with 2 identical drivetrains but 2 different drag coefficient

I have a Talon TSI AWD Turbo and a Mitubishi Galant VR-4. Both have identical Turbo/AWD setups and engines.

The cd on the Talon is .29 and on the Galant it is .34.

I was just wondering how much worse off the Galant is if all things are equal even including weight and tune.

Thanks
__________________

__________________
92 Protege DX 5 speed - Poor Man's Hybrid 40.96 MPG (city)

Thicker 2 row radiator, walmart hubcaps, Pepboys tires, 10w 30 Castrol HM, Jensen CD player, Roadmaster speakers, ebay hi-flow air filter, autolite 3924 plugs, stant superstat, NGK blue 8mm wires, LeBra car bra, no Exhaust Manifold heat shield, MX-3 Seats, bad A/C compressor
jj94auto is offline   Reply With Quote
Old 07-01-2013, 07:57 AM   #2
Registered Member
 
Join Date: Nov 2007
Posts: 1,460
Country: United States
Location: north east PA
It will come down to the trip. In town they will be the same or close enough not to matter.

I can't answer how much, but you probably won't have a noticable difference until you get up to highway speeds.
__________________

trollbait is offline   Reply With Quote
Old 07-01-2013, 10:34 AM   #3
Site Team / Moderator
 
Jay2TheRescue's Avatar
 
Join Date: Sep 2008
Location: Northern Virginia
Posts: 4,657
Country: United States
Location: Northern Virginia
Well, the example I can come up with is the 2010 Escape Hybrid fwd and the 2010 Fusion Hybrid fwd. The both have the EXACT same powertrain. The Fusion is rated for 41 City 36 Highway 39 Combined, the Escape is 34 City 31 Highway 32 Combined. That's basically a 7 MPG difference in the combined rating.
__________________






Jay2TheRescue is offline   Reply With Quote
Old 07-01-2013, 12:08 PM   #4
Registered Member
 
GasSavers_BEEF's Avatar
 
Join Date: Apr 2008
Posts: 1,831
I don't know how reliable it is but this web site says they have different final drive ratios which would greatly affect the mileage.

I do want to say that there is a huge weight difference too but I am not finding it. I assume that the truck is assumed to be used for more hauling and thus beefed up vs the car.

2010*Ford*Fusion Hybrid Specifications
2010*Ford*Escape Hybrid Specifications

There again, I don't know the reliability of the site and it may be dependent on package and options.
__________________
Be the change you wish to see in the world
--Mahatma Gandhi



GasSavers_BEEF is offline   Reply With Quote
Old 07-01-2013, 04:15 PM   #5
Registered Member
 
Join Date: Apr 2007
Posts: 57
Country: United States
Thanks all, the trip is almost exclusively highway. I know it is hard to figure out, but thanks for the examples. Both cars don't really weight the same thing, but I was just trying to simplify things a little. The Galant has been gutted for weight savings so in actuality it may be similar to the Talon in weight. It is not the same as comparing say an LT1 Camaro and an LT1 Impala SS. The weight difference is much closer to begin with between the 2 vehicles. The Galants weren't that large back then.
__________________
92 Protege DX 5 speed - Poor Man's Hybrid 40.96 MPG (city)

Thicker 2 row radiator, walmart hubcaps, Pepboys tires, 10w 30 Castrol HM, Jensen CD player, Roadmaster speakers, ebay hi-flow air filter, autolite 3924 plugs, stant superstat, NGK blue 8mm wires, LeBra car bra, no Exhaust Manifold heat shield, MX-3 Seats, bad A/C compressor
jj94auto is offline   Reply With Quote
Old 07-02-2013, 09:26 AM   #6
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
For a highway trip weight won't matter. If you're sure the entire drivetrain is identical (transmission ratios, final drive ratio, tire size) then you're looking at aerodynamic differences and probably some rolling resistance differences too.

Also don't forget that aerodynamic drag is not just the coefficient, but the coefficient multiplied by frontal area. Does frontal area differ much?
__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 07-10-2013, 11:52 AM   #7
Registered Member
 
1993CivicVX's Avatar
 
Join Date: Aug 2007
Posts: 1,066
Country: United States
Send a message via AIM to 1993CivicVX
I dunno if weight won't matter, but perhaps it will matter less, particularly in flat areas. But hilly areas it will certainly matter on the highway.
__________________
three stripes the charm!

Car mods are overrated. Just gotta adjust that nut behind the wheel for best mpg.



Forget about World Peace...Visualize using your turn signal.
1993CivicVX is offline   Reply With Quote
Old 07-10-2013, 12:02 PM   #8
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
I don't see why. You store energy while ascending and release that energy while descending, there's no reason to lose anything. If anything it'd be an advantage, allowing you to P&G on the highway while keeping a steady speed.
__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 07-10-2013, 12:13 PM   #9
Site Team / Moderator
 
Jay2TheRescue's Avatar
 
Join Date: Sep 2008
Location: Northern Virginia
Posts: 4,657
Country: United States
Location: Northern Virginia
I get some of my best mileage in the mountains. It may totally suck going up the mountains, but going down more than makes up for it in my case.
__________________






Jay2TheRescue is offline   Reply With Quote
Old 07-12-2013, 07:45 AM   #10
Registered Member
 
i-DSi's Avatar
 
Join Date: Nov 2009
Posts: 179
Country: United States
Mountain area should almost always be worser for mpg, because when going down there's definitely corners where you need to brake/engine brake and you can not keep on 'gliding' downwards.
That's all loss of energy.
Can imagine it's a bit better on highways, but for safety you need to keep a bit of steady speed, no?
__________________

i-DSi is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
My experience with Airtabs JudithGordon Experiments, Modifications and DIY 8 05-13-2014 09:33 AM
Tire sizing odometer modifier? BDC Fuelly Web Support and Community News 10 07-25-2009 09:59 PM
MID Install SVOboy Experiments, Modifications and DIY 33 06-04-2007 11:27 AM
SuperMID speed sensor compatibility Matt Timion General Discussion (Off-Topic) 11 06-14-2006 10:47 AM
Alternative Fuels blacktone Fuelly Web Support and Community News 2 05-21-2006 12:32 AM

Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 01:41 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.