New hot rodder type

[bobesser]

Originally Posted by renault_megane_dci

What is your commute ?

How do you drive ?

Honestly, I can't see much FE improvement coming from ecomodding the car.
It is already very much refined to be performance vehicle with a very big engine and such.

I tend to drive spiritedly once in a while, coming from motorbikes.
Thing is I have much more fun going flat out with a much smaller engined vehicle than I do allowing me to break the law once in a while with my regular car, not to mention the safety issues. And it's not even sporty !

So I seem to recall you're telling us that you use a M3 as a daily driver and that you don't break the law with it and that you drive hard on the track ?
Yeah, right !

Each to their own but an econo box on the side of the M3 is going to pay for itself in no time ...

Try P&G one of these days, it's much funnier than you think.

As I said, I don't drive like an idiot, but, I do keep up with traffic, which in DC can be 80 mph.

I had a motorcycle that I wish I hadn't sold (Ninja 500) and I plan on buying an older Ninja 250 very soon. The new bike will likely be the basis of more serious MPG efforts. (This will be my 'econobox')

Originally Posted by UFO

I like track racing, and I like commuting to save fuel. Two different ways to enjoy driving. I slowly got into hypermiling; it's too much of a challenge and requires too much attention to go all in at once with P&G.

Try coasting out of gear to known stops. Turn off the engine at long lights. Accelerate briskly without higher rpm to your target speed and get into high gear/low rpm to maintain. I am constantly challenging myself to maintain momentum through curves and turns, and timing traffic signals to minimize braking.

Spirited driving doesn't always have to be about all-out acceleration or rushing up to stops.

I guess, it helps to look at it as hypermiling is a different sort of precision driving.

Bob

[elhigh]

I was going to suggest spending what you might on another set of wheels/tires on a cheap commuter...but I couldn't do it. You already have to sit through a commute, you shouldn't have to punish yourself by giving up that BMW interior to do it economically.

I know DC driving. I grew up there. And yeah, there are places where 80 is what it takes to not get somebody up your tailpipe, shouting imprecations.

At this point, I'm out of suggestions.

[UFO]

At 80mph there are huge gains to be made in aerodynamics, but I doubt this is going to happen with a BMW, I certainly wouldn't do the mods.

[Frank Lee]

If you go in the triple digits speed range you can get transonic flow which as we all know has much lower aero drag.

[CFECO]

Originally Posted by UFO

At 80mph there are huge gains to be made in aerodynamics, but I doubt this is going to happen with a BMW, I certainly wouldn't do the mods.

Why?

[renault_megane_dci]

Originally Posted by CFECO

Why?

I guess because late BMW are already very much refined in this department and that aero is often a compromise that we, individuals, can very difficultly evaluate and alter for the better.

Modding an 80's econobox is far easier.

[justme1969]

I played with my tire size untill I got a best case scenario at 75mph.
Not a hot rodder per say just going with speed of traffic mostly.
Lowering my engine rpm @ 70 mph untill I best used inertia and engine torque at that speed.
Now this resulted in a ride height difference of 1.75" so I installed a chin spoiler, and side skirts instead of belly pans. {those may have proved better not sure>}
Then I worked on aero by deleting the passenger mirror and folding back drivers side.
next I moved tail spoiler as far back as possible on the trunk
Next I added wheel disc covers.
Little things like a wiper shut off help little, but items like engine kill switch and push button start helped final effect by making P&G and engine off coast down easier and saved on motor mounts and clutch.
My POS can really coast engine off now and cleaning and relubricating drive line helped alot.

I hope this helps you some and happy motoring.

[Daox]

Originally Posted by renault_megane_dci

I guess because late BMW are already very much refined in this department and that aero is often a compromise that we, individuals, can very difficultly evaluate and alter for the better.

Modding an 80's econobox is far easier.

I've modded my Prius for better aerodynamics, one of the most aerodynamic production vehicles. There is plenty of room for improvement on his car.

Just looked it up, the drag coefficient and it is .30. That is really not all that slippery.

[UltArc]

Have you done any modifications so far? If you're monitoring temperatures and in regular driving, grille blocks should be in line, and can be tasteful.

I saw you mentioned the exhaust, but an underbody would be a great point to expand on. mcsrews was successful with his Q45 build, and my polycarbonate hasn't had an issue yet.

Rear wheel covers could be in line, but definitely more noticeable. Have you went through 65+ Vehicle modifications for better fuel economy - EcoModder.com for ideas while you start working on what you like from 100+ Hypermiling / ecodriving tips & tactics for better mpg - EcoModder.com

It will be a little while before aero mods will be more so beneficial than driving technique, but the DC commute will help. I found my FE wasn't so bad at higher speeds in the traffic, but I imagined it because we were such a cluster moving through the air.