better mpg after lowering?

[deltatechx]

Has anyone noticed an increase in fuel economy after lowering their 8th gen? I saw this on eibach's website:

Eibach Springs - Performance Suspension, Lowering Springs, Shocks, Sway Bars, Coil-Overs and Wheel Spacers!

I know it's only 3 mpg, but that's with "spirited" driving. I'm hoping that under normal driving conditions the mpg would increase by at least 6 mpg. Again, that may not seem like much but when you use 20 gallons of fuel a day it adds up quickly (about a $53 savings per week @ $3.60/gal), it would easily pay for itself within a month, including the camber kits. So if anyone has actually kept track of their mpg since before they lowered their civic till after, please post if there was any change in mpg (increased OR decreased).

Thanx -- Paul

[deltatechx]

bump for any help on this, I've done a search and haven't found any threads pertaining to this.

[Izzy]

I can *sort of* see why lowering the car would help with MPG, but I don't think 6mpg is viable and even 3mpg appears to be pushing it.

[Monsterbishi]

That seems rather impossible, i'd have to go ahead and say no, maybe its the way you drive now, but lowering your car did not and will not increase your fuel economy.
-Paul

[Chyna Black]

I am going to have to say no as well!

[Mcgruber]

maybe you get better mileage now because you take it easier over bumps instead of just driving through it in .. lol

[habitat]

Originally Posted by Izzy

I can *sort of* see why lowering the car would help with MPG, but I don't think 6mpg is viable and even 3mpg appears to be pushing it.

I'm with you on that, I can see that lowering your car can reduce underbody turbulence (drag) and create smoother airflow overall (more effective at higher speeds). But no way that can achieve an increase of 3mpg... I'm guessing more like fractions of 1 mpg here. If lowering your car did that much, Civic Hybrids would be slammed to the floor!

[Izzy]

Yeah, the test was with a TRUCK, which sits high in the first place, so reducing drag would be easier with it than with a car like ours already.

Our cars are fairly smooth under-body, too, so I still can't imagine this making too much of an impact.

[buurner]

interesting!!!!!

[M1C. MON5T3R]

interesting indeed...bump

[OrdnanceMarine]

I saw a *slight* increase on my previous '00 Accord Coupe when I dropped it on Pro-Kits. On highway trips while cruising at 65 mph or greater it was probably on the order of 1-2 MPG. Keep in mind that this was a car with underbody aerodynamics that are inferior to the current Civic and the drop was 1.5" which is more than the Pro-Kit drops the Civic (I believe). I'd expect to see an improvement since you are reducing frontal area but something less than the 1-2 MPG I saw on my Accord.

1 MPG (say from 30 to 31 MPG) over 100,000 miles at $4/gal would save you about $400. Not huge, but a good way to justify lowering your car to your wife!

[deltatechx]

That seems rather impossible, i'd have to go ahead and say no, maybe its the way you drive now, but lowering your car did not and will not increase your fuel economy.
-Paul

I never said I lowered my car or that it would give better fuel mileage, I'm asking if anyone has experienced first hand what Eibach claims on the linked page.

Yeah, the test was with a TRUCK, which sits high in the first place, so reducing drag would be easier with it than with a car like ours already.

Our cars are fairly smooth under-body, too, so I still can't imagine this making too much of an impact.

I was actually referring to the Honda Accord on the bottom half of the page, guess I should have specified that.


Thanx for your input, I figured it wouldn't be that drastic of a change but I just wanted some input from people that have lowered their 8th gens and could give a definite yes or no on the increased fuel economy from their own experience and not theory or claims from the manufacturers.

Thanx again
- Paul

[habitat]

Originally Posted by OrdnanceMarine

I saw a *slight* increase on my previous '00 Accord Coupe when I dropped it on Pro-Kits. On highway trips while cruising at 65 mph or greater it was probably on the order of 1-2 MPG. Keep in mind that this was a car with underbody aerodynamics that are inferior to the current Civic and the drop was 1.5" which is more than the Pro-Kit drops the Civic (I believe). I'd expect to see an improvement since you are reducing frontal area but something less than the 1-2 MPG I saw on my Accord.

1 MPG (say from 30 to 31 MPG) over 100,000 miles at $4/gal would save you about $400. Not huge, but a good way to justify lowering your car to your wife!

The problem with your reasoning is that it is hard to prove that lowering your car = MPG increase from other random natural factors. They include, changes in weather (both heat/cold and rain/dry), variation in fuel quality, differences in drive setting, and also human judgment/error. All these factors can alter your MPG by 1 or 2 points, therefore it is impossible to say "lowering my car increased my MPG by 1-2 points" without increasing the sample to normalize the distribution.

[OrdnanceMarine]

Originally Posted by habitat

The problem with your reasoning is that it is hard to prove that lowering your car = MPG increase from other random natural factors. They include, changes in weather (both heat/cold and rain/dry), variation in fuel quality, differences in drive setting, and also human judgment/error. All these factors can alter your MPG by 1 or 2 points, therefore it is impossible to say "lowering my car increased my MPG by 1-2 points" without increasing the sample to normalize the distribution.

True, there's no way to beyond a doubt attribute any change in MPG to any modification unless you had a way to track variables and essentially remove the "noise" from your data. What I did do is looked back on my fueling log that covers the entire history of said vehicle. I swapped springs in July, 2001 at about 13000 miles which is about the hottest it gets in Prescott, AZ and was plenty of time to break the car in. During this period of time my driving routine was very consistent. Drive to the university in the morning, drive to the flightline after class in the afternoon, drive across town to work after that, drive home, repeat. Much of this was at 55-65 mph and any excursions from this schedule can be assumed to be relatively random and normalized over the course of 8 months. Any variations due to weather conditions, whether seasonal or diurnal, can basically be canceled out since the period I'm looking at was April-November. Fuel should have been fairly consistent since I always fueled at the local Costco and I'm unsure if there was any change in the fuel blend in rural Arizona during the year but I'm sure they wouldn't be doing the shift in July.

Anyway, I'm probably more methodical that most folks WRT this topic, at least I hope so since it's essentially part of what I do for a living so you're welcome to take or leave my simple analysis. What I do see in my log (which I track at Fuel Economy) is an awful lot of 36.X MPG tanks and a few 34.X and 35.X tanks and a high of 38.7. Post 1.5" drop I see a bunch of 37.X MPG tanks a few 38.X MPG tanks and a high of 40.0 MPG.

Again, you're right, I can't prove beyond a reasonable doubt that dropping my Accord 1.5" yielded ANY improvement but I came to the conclusion that it did based on some sort of somewhat creditable procedures and didn't just use the “anal extraction” method to gather my numbers and conclusion.

[madmatt]

Perhaps they considered the decreased unsprung weight as well? How much lighter are the Eibachs than the stock stuff?

[24boosted]

Possibly because lowering the car also changes overall aerodynamic characteristics. Either lower front or lower rear, change in down force with less air flowing underneith the car. OR it's all in your head.

I know I get GREAT gas mileage now with turbo only because power comes in so soon I don't need to push it to get the car going.

[GALAXY~SI]

is this serious i cant believe they said lol

[07 fg2]

i do drive slower on side streets due to my hfps. maybe people are driving slower to avoid potholes and harsh ride.

[NASAMike]

no way

[mrbill]

There's no question that lowering the car decreases drag (and lift).

If you've got a Sedan, putting the undercovers from the Hybrid will decrease drag for far less money. (Still would love to know if they'd fit on the Coupe.)

The only question is how much it will help MPG. Without more details on the "high-performance testing/driving" you won't know.

Bottom line - if you are considering lowering your car to help your MPG, there are better places to spend your money first. But if want to lower your car and you want to know if it will help or hurt your MPG, it'll help.

-mr. bill