I am telling you guys... my parents go on trips like more than half of the months out of the year. When my 04 Coupe is loaded up with the three of us PLUS their luggage, I get a consistent 29 mpg on the freeway...

BUT on the way home, I get 25 plus mpg with the car empty.

I tested it this morning.

My car is OEM except for staggered 17" 2005 C sedan rims. (well, 05 tails/wood trim but this isn't about handling or mileage).

Does lowering the car make it get better mileage?

If so, I'm game. As a girl, never really understood what the purpose of lowering is, is this a benefit?

 

How about the hills? Does the grade slope toward the airport?

 

Who is doing the driving? When everyone is in the car are you still the driver? Chances are the person is driving slower and coasting to stops.

Just my thought.

E

 

My thoughts exactly - otherwise it makes no sense

 

sounds like this girl has to many things on her mind..

Keep driving babe how many miles are on your car / year / etc .

Make sure to fill up with chevron with techron.

 

What a sensible recomendation

 

Matter of fact, it is filled with Chevron.

I drove both ways. I looked up stuff on aerodynamics and I think the lowering springs actually does increase mpg.

I'm starting with getting a front lip and see what happens.

 

Wonderful - my old company for 37 years.

The sort of differences you are talking were not achieved by the change in attitude by loading the car - This I can say without fear of contradiction

 

i had something similar hapen to me.. road trip to SF from LA..
on the way up 29.5.. on the way back with a full trunk and back seat.. 34mpg


crazy hu!

my average now is 33.5 to 34.8 on hwy now...

 

that's because when you head SOUTH you're going downhill....

 

Noticed it on way up and back twice to La Jolla, btw.

Once with me alone in the car, the other time with a friend.

27.5 average with friend.

about 25.6 average with me alone.

I'll let you guys know. Something to do with air flow under the car as well as rounded airflow off the back of my oem coupe with no back lip.

 

omg...

 

lowering the car does reduce the turbulent air under the car which could improve some mpg, but it is very minor.

I'd say it's just because when you are driving with a friend you are less likely to go fast when you are talking with your friend.

 

Here are a few sites that talk about this:

From "Car Aerodynamics 101":

According to Mercedes, "Lowering the ride height at speed results in a 3-percent improvement in drag."

http://www.recumbents.com/car_aerodynamics/

http://ecomodder.com/forum/showthrea...gain-4589.html

 

A Moderator with a sense of humour

 

+1 - I know all about air under cars & have spent time in a wind tunnel - ran a race team - done endless research on fuel consumption etc. By the way the cd on your car is pretty good to start with +- .27 I think.

 

I know i almost fell out of my chair when i saw that..

anyways i think your tripping to much its a computer doing research from your gas pedal. Maybe your foot played a good roll with your estimated MPG.

Anyways but yeah going north on the 5 freeway is a little up hill

 

Just like what glyn was saying, these cars already have gone through wind tunnel test, i doubt the lowering the would really alter the drag coefficent much.

Even shedding 100lbs worth of weight only adds 3% in fuel economy.

When your car is fully loaded with people and luggage, are you going on a long drive?

Long highway drives going at a constant speed will yield better fuel economy then driving alone in the city and highway or on the highway through traffic, even with the added weight.

I got 27mpg in my c32 coming from vegas to LA with my gf and 3days worth of luggage. When i'm by myself driving on just the highway to work i would get around 23mpg.

http://www.fueleconomy.gov/feg/driveHabits.shtml

 

Yup! & it takes a lot more energy to get a heavier car up to speed but not that much to maintain it all things remaining equal. All a matter of Physics

 

Well, I don' t weigh that much. 128 on a good day. Guys I really do think my car got better mileage going about a 35 minutes down the 405 to LAX with my parents and luggage in the car. When I pick them up in a few weeks, I'll report on it again to you guys and be very careful about speed.

Meanwhile, I'm going to get a lip on the car before I try the h and r lowering springs.

 

i would never read what my cluster say, is never accurate

the best way is drive on curise control for 50+ miles, fill up your car and see how many gal u have to fill, then do the math

my coupe always say 31+ when i drive from santa clara to gilroy everyday

and when i fill it up, my math show me 27 MAX

and i am a guy, really perverted one, love girls under 16, weight almost 200 lbs, i lower my car with Coilover, not spring. (so wanna join me??)

i drive alone, so i think my coupe is one way lower than the other, i got front lip, i don't see i get better gas mileage i think the lip actually blocking air so is actually slowing me down then i think i need to buy lot of "KY jelly" luburcate the exterior of my coupe so i can get up to 36MPG

 

The outside air temperature could affect your mileage. About 65 to 75 degrees Fahrenheit seems to deliver the best mileage. Hotter or colder than that will decrease your mileage somewhat.

Fuel can also affect your mileage. Winter gas vs. summer gas, ethanol added vs. no ethanol, higher vs. lower octane, etc. You probably filled up somewhere enroute, and the gasoline formulation was a bit different.

My C230k seems to be very particular about gasoline quality.

 

+1 - People that have never seen an engine on a dyno in controlled conditions have no idea what 1 deg inlet air temperature change does to performance - or if you don't make use of that performance - then gas mileage

agree on fuel

 

she lives in southern california, so there's the same amount of ethanol in the gas year around for emission reasons.

i think the gas quality should be the same since majority if not all gas stations in southern california are branded gas stations.

 

Yep - good point --- cursed LAX - I just about had a tent in that place at one time