It's the drag, man...

[DRW]

I like this topic, there's nothing like an open-ended question to spark the imagination.

There are many ways of lowering drag, it's just a matter of putting in the time and effort to attain those improvements. Then there's the question of value; how much time and/or money does it take to get X ammount of improvement?

About your comment about greasing wheel bearings really well, adding more grease will increase a bearings viscous drag because the grease is constantly being pushed around as the wheel turns. I happen to work in the bicycle industry, and the fastest bearings are ceramic ball bearings which use no grease. Second best is a typical sealed cartridge ball bearing with the seals removed, grease flushed out, and a light oil used as a lubricant- these get dirty quickly and need to be replaced. Obviously this is not practical for cars, but the point is to use light weight synthetic grease, and use it sparingly. Make sure the seals are making light contact, and lube the lip on the seal.

Engine and tranny oils have been covered in other threads, and the conclusion seems to be to use light weight synthetic oils, and to slightly underfill it.

How about shaving the sides of tires? There are two benefits for this one, to smooth the sidewalls for less air drag, and to reduce rolling resistance. There might be a tradeoff of reduced durability if it's taken too far.

How about cutting a larger central channel in the tread of the tire to mimic a trucks dual tire? It might also give air a place to flow through instead of being pushed around to the sides of the tire.

ECU program tailored to each individuals preferences. I wish everyone had a programmable ECU like I do. I've found about two dozen areas that have the potential to improve FE to various degrees. There are portions of the timing and fuel maps that seem to be set up to make the car easy to drive at the expense of FE. I have a feeling the engineers were more concerned with making the car easy to drive for the worst drivers so that customer satisfaction is highest. That's an area I (and I'm sure others) would gladly sacrifice to meet their own individual needs, habits and driving style.

[BEN_EJ8]

So how do you like your Laser? I had the exact same thing about 2 years ago, funnest car Ive ever owned by far. When I saw you are doing 37 mpg I instantly thought you had the 1.8, but the 4g63 getting that mileage is incredible. Especially since that tiny turbo would hit full boost by -+ 2100 depending on which gear. I had to get rid of mine because it lived up to the DSM reputation

Your car probably runs low 13s and gets 40 mpg, cant ask for more than that

[The Toecutter]

Adressing aero drag is where the largest overall fuel economy gains can be made, assuming about an even mixture of city and highway driving. Going from a .32 to .16 drag coefficient in today's cars would increase combined mileage by about 40%, with no other changes. This is the ticket to 30-35 mpg V8 musclecars and 35-40 mpg V6 sedans that use no weight reduction, no hybrid drives, no diesel engines, no LRR tires, or any other mods. With LRR tires, synthetic gear oil, weight reduction of 300-400 pounds by removing all sorts of useless interior filler, and other mods on top of extreme aerodynamic efficiency, 35-40 mpg combined V8 musclecars and 50+ mpg combined V6 family sedans become possible, which would incur no cost penalty, no horsepower or engine displacement reduction, no size reduction, no comfort reduction, and in most cases, an increase in cargo capacity. Going from a gasoline to a diesel engine or to a gasoline-electric hybrid drive would improve fuel economy by about 30% given horsepower remains similar. Going to a diesel-electic hybrid drive would improve economy about 50% over gasoline given that horsepower remains similar. This is how cars like the GM Precept got 80 mpg, while still being the same overall size as a Ford Taurus, and still managing 0-60 mph in 11 seconds: extreme aerodynamic efficiency, weight reduction, and diesel-hybrid drive.

Read the following article:

http://www.evworld.com/blogs/index.c...d=87&archive=0

Yes, the methodology is a little flawed given that it is an estimation, and the flaw is particularly egregious that it is a linear estimation, among other noticable flaws. I'm working on an updated article that uses a larger sample size, uses a nonlinear approxomation by finding a paraboloid of best fit, and factors in peak motor horsepower as well, to estimate the effects of having a more powerful engine on fuel efficiency. So far, I've played with what numbers I've derived with my current sample size of over 80 cars, and that's how I arrived at the possibility of 35-40 mpg combined V8 musclecars with 350-400 horsepower.

Extreme cases like the Opel Eco Speedster sports car get 94 mpg. It has a .20 drag coefficient, ~15 square foot frontal area, and weighs ~1,500 pounds. It's engine is a 112 horsepower inline 4-cylinder turbodiesel. It tops out at 160 mph, and would go faster if the governor were removed.

High performance and high fuel economy can coexist, while still remaining affordable. But the auto industry refuses to go that route. It would rather push onto us high-maintenance gasguzzlers with high profit margins.

[DracoFelis]

Originally Posted by DRW

About your comment about greasing wheel bearings really well, adding more grease will increase a bearings viscous drag because the grease is constantly being pushed around as the wheel turns.

I was aware of that, but it is worth repeating.

OTOH you have to work with what you have. For example, my mechanic could "easily" drill a small hole in the rear wheels to put in a grease fitting to add grease, but removing the old grease junk would have been a lot harder. So we "made do" with squirting a little new synthetic grease in there without removing the old/junk. Even though this situation wasn't ideal (it would have been better to get the old junk out, and only use a little new grease exactly where needed), it still made a HUGE difference in how freely the wheels turned.

Originally Posted by DRW

I happen to work in the bicycle industry, and the fastest bearings are ceramic ball bearings which use no grease. Second best is a typical sealed cartridge ball bearing with the seals removed, grease flushed out, and a light oil used as a lubricant- these get dirty quickly and need to be replaced. Obviously this is not practical for cars,

I'm not so sure the concept wouldn't work. For example, has anyone tried plating all the moving surfaces (including each individual bearing) with Moly (a very good high-pressure dry lubricant)? I probably won't try it (due to the hassles of tearing the wheels fully apart), but it sounds (at least at first glance) like that could result in very freely turning wheels.

And if Moly isn't "high tech" enough, just consider some of the dry "Nano-Lubes" that some companies are working on. If you could work out a cost-effective way to "nano-lube" up the wheels, you may end up with easy turning wheels that stay lubricated.

Of course, neither of these approaches prevents you from also using good synthetic grease. And depending upon their lubrication properties, it might even be useful to do so (i.e. combine Moly plated metal parts with small amounts of synthetic grease). But the point is, there are dry lubricants (some of which, such as Moly, which can be "plated" to moving metal surfaces), that could be usefully used in a car...

Originally Posted by DRW

but the point is to use light weight synthetic grease, and use it sparingly.

FWIW: This is the stuff I used in my car, and so far I really like the results.

https://www.amsoil.com/storefront/grg.aspx

Originally Posted by DRW

Make sure the seals are making light contact, and lube the lip on the seal.

Good to know when you have a choice in the matter. But in our case, just getting the grease in any way we could (when the bearing unit was designed to not be greaseable at all) was our (mine, and the independent mechanic I use) first concern. Because even if we couldn't get the ideal greasing situation, just getting some good synthetic grease in there (after 15 years of nothing being done) was going to help a lot more than it hurt...

Originally Posted by DRW

ECU program tailored to each individuals preferences. I wish everyone had a programmable ECU like I do.

Cost? Difficulty in installing? Which cars is it for?

I would be happy to consider a programmable ECU for my 1991 CRX. However, last I checked it would run me several hundred dollars for one, and even more for the EPROM programmer. And I just am not yet ready to fork over that much money to upgrade the computer in my car...

[red91sit]

Originally Posted by DracoFelis

Cost? Difficulty in installing? Which cars is it for?

I would be happy to consider a programmable ECU for my 1991 CRX. However, last I checked it would run me several hundred dollars for one, and even more for the EPROM programmer. And I just am not yet ready to fork over that much money to upgrade the computer in my car...

If your comfortable with a soldering iron, you can run one of the free programs out there, and buy a cheap ($10-25) ECU chipping kits. Then all you need is a chip burner, or a chip emulator. I have aMoates.net Ostrich, GREAT service there too! I'd highly recommend it to any one. If you have a lap top (with USB port), you can buy the HULOG and datalog too!

I'm considering getting the FordEmu too, so I'll have to fully programable cars haha.