Weight factored FE?
 

At lunch Friday, a friend of mine was recalling his college days in the '60s. He participated in some FE rallyes in British Columbia. He said they used a weight factored scoring, but couldn't remember the details. Have we ever looked at a weight factor. For example, a per thousand pounds would be a way to measure the relative FE of different vehicles and modifications. This would not be a substitute for the raw numbers, but could prove interesting.

That would be an interesting factor to introduce. Would that mean my sub 2 ton Bel-Air at 25MPG would be equivilent to a just over 1 ton 50MPG Civic vx?

In principle--yes.

buy why? thats like asking to factor in a vehicles aerodynamics to "level" that playing field.

Good point, there are only so many things you can level off before everyone gets the "same" gas-mileage.

Hey, I have to drive 80 to avoid getting run over. I need a handicap!

Actually the roads around here aren't too bad. They don't mind me going 50-55.

If you'll note in my original post, this was part of an economy rally done years ago. It was used to provide way to weigh a variety of vehicles and driving skills. I was simply asking if anyone had considered it. I agree, there's a limit for trying to control for variable.

On the subject of an economy rally. Does anyone know of any currently being run? Just curious.

When I was a kid, the Mobil ecomony run was well known.

Graeme, it isn't raw numbers, it real MPS vs EPA estimates so it's basically us vs what the manufacturer said it c(w/sh)ould be.

Graeme -

I think it would be worthwhile because it can be useful to look at the data from different POVs. This reminds me of another thread :

Cost per mile?
https://www.gassavers.org/showthread.php?t=2940

CarloSW2

my wife's FE is "penalized" by extra weight(3 kids),idling in the school rider line, AND she's not a hypermiler!

I'm not sure who is being penalized :) Some places of the world it is illegal to idle excessively (and yes I've heard all the excuses for doing it).

actually to be more specific, my wife leaves early and parks(engine not running)waiting for the kids. then, when loaded, is stuck in slower than stop and go traffic exiting the school. its more like go,stop,idle...repeat. you know what i'm saying. in fact when i go to get them once a week, sometimes it takes a while to "get in" initially. we're not into repetitive shut-off especially in a moving line no matter how slow it is. starters aren't cheap. and yes i DO see the SUV driving soccer moms idling away(while waiting) contributing to GW,pollution,oil profits, or whatever else you fancy.

It would be very interesting since my main vehicle weighs 4 tons hitched and loaded, might actually make my 11mpg a lot more challenging than it would appear.

Well you could have different "classes" like regular races. Would be interesting.

*********************or*****************

Handicap based on most current 90 days mpg average.

You'd need to factor in the factual need for a heavier vehicle along with it's weight. If you really need it and it weighs four tons, that's fine. On the other hand, if it's just for show...

So far I'm "good" with the system we have where you're basically challenged against the car's EPA rating. If you're driving something with EPA rating of about 19 mpg (like yours truly here) and you can get 25-30 mpg out of it, well that's decent. If a car's EPA estimate is 35 and it's only getting say 30, then you probably could try harder. With all the money and technology behind the EPA testing I think it's probably a pretty level playing field.

I think nearly any one of us would buy a "next" car getting significantly better mpg than the one we're driving now. But there are years in between those purchases, it's just a fact of life for most of us. It's usually pretty wasteful financially to change cars more often than that. Which only leaves someone else driving your former ride, anyway, unless it goes to the crusher. Someone who might let it idle in the driveway.

brucepick...why do you use 19.5 vs 19 for mixed (19.0 is the new EPA estimate)?

Dunno. Maybe I averaged the city/hiway and got 19.5. Seems they always round the #s. Also somewhere I saw EPA #s given to tenths of a mpg but I didn't note where that was.

Maybe I should change my entry - might actually not be right as it is.

I am a landscaper, I work from my home, the truck and trailer is what I carry my equipment on so I can service customer lots. The 1995 D2500 slt is rated EPA 11 city 15 hwy and its curb weight is 5030 pounds, unfortunately I can't get exact stats on the trailer but it's between 1500 and 2000 pounds, empty.

It might seem like mpg would be the last thing I'd worry about, but I could say the same thing about hybrid owners why are they worried when they're already getting great mpg... Fact is a 10 percent loss in fuel efficiency can translate to 600 dollars a year.

The cost of doing business directly affects my earnings as an owner-operator, the cheaper I can run my operation, the more money I get to keep in the bank.

Unlike these landscapers you see running around with these huge 16-foot steel double axle trailers loaded with at least 3 lawn mowers and gas cans and half a dozen string trimmers and blowers and then a wheel barrow and pitch forks and rakes and shovels, that is not me.

Although it would take 800 pounds to make a real difference all it takes is an extra mower weighing 3-500 pounds, then add fuel cans full of gas weighing 40 pounds each, now throw in all that extra hand held equipment and you have 5-6 maybe 700 pounds... I carry only what I need for the day.

I usually carry one lawn mower which I use on most lawns, one trimmer and one blower, no extras. No spare fuel on board, no cans, I have a syphon in case I run low but most of the time I can run the entire day. Yes I can hypermile a string trimmer, I do 8-10 lawns on one tank of trimmer fuel, thou this translates into ounces per lawn and not miles per gallon, still it's efficiency at work.

About the only thing that is overkill is the truck, I don't NEED an slt, that is an ultra-luxury truck with cruise control and tilt steering and power mirrors and all, a bare basics work truck would do... But I did drive for 5 years in trucks that had no a/c no radio no nothing... Man you're lucky if the crank handle for the window doesn't fall off and if the wipers work that is a bonus too, yes sir I believe in Rain-X, so just for once in my life I felt like I owed it to myself to splurge a little, but this luxury does cost, I admit that much.

Hope that helps clarify my position.

I do agree thou, entirely fair it isn't and it can't be.

Aerodynamically my truck is a pain but then my trailer gets drafted :p
Now take an 18-wheeler and we have a serious problem, simple fact is those things might only get a few mpg but they also haul tens of thousands of pounds yet their engines are diesel so again the equation gets thrown off.

I see the point, by the time we factor in weight we might as well factor in extra passengers and time spent idling, well heck how about hills, sure and soon the argument never ends.

So it might be this is something we may never be able to figure out without blowing the initial goal out of the water, thou I can rest easier knowing folks now realize the big rigs and those in between such as myself DO take mpg seriously, because it does matter.

If nothing else that's the only thing I wanted to accomplish, if we ever get a mpg per pound standard worked out that would be great, but if we don't that is not the biggest threat to my sanity either :p

Hi 8307c4,

This all makes sense to me. You certainly need what you're driving to do your work, and as you pointed out there are likely many in the same line of work who aren't nearly as thrifty with fuel.

I certainly don't begrudge you the fairly common luxuries your truck has. Many if not most new cars and trucks have a similar or equivalent list of creature comforts. AC would add to fuel costs, but I don't think anyone would deny you that on a hot day (I don't know if you have or use it). Besides, with the trailer and load, the additional FE cost of AC would probably be negligible.

And while there's an EPA estimate for the truck, there's no estimate for the truck plus your particular trailer + load. Let alone an EPA estimate for a "standardized landscaper's load" - that would let you can see how you're doing better than "standard" from your efforts to minimize your load and use fuel efficiently in various ways. I think we don't want our government being that big.

Two ways I like to gauge my own FE are 1) compare with EPA and 2) compare with my numbers for same time last year. Both give me a idea of how I'm doing without beating me up (usually).

Right now, the "same time last year" thing falls apart for me, because I'm out of work right now. So instead of commuting approx 60 mi. each way daily, I'm running a few errands and/or driving to a rehearsal or two, each week. The short runs are yielding lower mpg numbers, but the good news is I'm buying a lot less gas! My last fillup was 12/4 and I've used just over 1/2 my available range in 9 days.

What's my point? I guess ya gotta give yourself credit for your efforts for FE, and certainly nobody should assume that a work or commercial vehicle is being wasteful just because it's big and it's there.

Yup Darby, looks like I was in error. Seems to me the "combined" isn't an average of city/highway, but slightly closer to the city number. Anyway the EPA combined for my car is 19 as you pointed out.

I've just changed Sven's Garage entry.

Thanks. Shoulda seen that one myself.

the EPA 'combined' estimate is based on 55% city and 45% highway. I guess I'm cheating competing against that estimate, since my commute is about 85% highway. Oh well, we're all using the same combined estimate, so I guess that makes us even. :) I saw one entry in the garage which said it was using the "correct" estimate based on his actual amount of highway driving. I guess he's AR. hehehe

Well we could always make it like the Tour de France. I guess heavy pigs like mine could compete for the green jersey despite the paradox of that while the lightweights could get the polka-dot jerseys... ;)

Couple of thoughts:

Aircraft performance (MPG is just another corner of the performance envelope) are always compared at max gross weight.

Trucks and trains are evaluated on the basis of ton-miles per gallon, but the tonnagge is only the payload tonnage. Payload ton-miles are what the billing is based on.

Trains get staggering ton-MPG. 600 ton-mile/gallon is common.

Trucks that get 7 MPG loaded to 25 tons of payload (175 payload ton-miles per gallon) are common as dirt.

Ok, what about when there is no EPA data on a vehicle? I like the weight thing. I think I win...LOL!

I'm intrigued by this I really think the % over the current EPA rating would be a fair challenge. It would be a challenge because then no one is favored and the challenge is to better the EPA rating by the largest amount over a 90 day period. the gas receipts and ODO readings need to be verified probably with photographs.

I'd win since I have no EPA standard. 1,000,000% increase...LOL!

Our club is holding Economy Run events and we in fact have a weight factored award. This is how it works:

Best ton-mile per gallon [TMPG] vehicle weight in pounds, divided by 2000, times miles driven, divided by gallons consumed. A handy calculator is here.

Our next event is October 5th and details can be found here.

Has that event been held before? I'd be interested in seeing results from it...

Yes indeed. The results are here.

Mike

That's cool. I like seeing the 95 Suburban in there... ;) His mileage isn't all that good though. Even driving my 98 K1500 (same body, pickup model, probably same engine((350 V8)), and 4wd) I get better than that in stop & go driving. If it was a little closer I'd consider going to something like that.

-Jay

Would TMPG competitors be able to carry ballast? A ton of weight in my truckbed puts me at a decent 54.4 TMPG.

I'd win the TPMG competition towing my camper. 14,400 pounds total weight and 10 mpg shoving it up mountains as hard as I could without any regard for FE; I'm sure I'd get 12mpg now unless it was 100% stop-and-go. That's 86 TMPG by your calculator...

If I stop by the quarry before I leave town I can get a ton of bluestone gravel in my pickup truck for $10... ;)

-Jay

I'd have to say no because our electronic race car scales don't go high enough. When we drove the 6,400 lb. Suburban onto the scales the digital readout went to all zeros. We then realized that we could not accurately weigh the Chevy so we used the curb weight on the vehicle registration instead. Also, the only reason the Suburban was there was because our August Economy Run event preceeded our club picnic later that day and we knew that entire families would be coming along. So we offered an award for the Worst fuel mileage to encourage people with gas guzzlers to particpate. That's the reason why the [454 c.i.] 4WD Suburban only got 11 mpg. He wasn't hypermiling one bit.

The weight on the registration may have been GVWR (maximum legal weight with a full load), not curb weight. Many states (mine, for example) do it that way.

Perhaps a nearby truck scale (truck stops, gravel yards, landfills, transfer stations, some trucking/multimodal hubs), or the police/DOT, would be willing to help weigh the heavier vehicles?

My VW would come in at a respectable 66 TMPG with a full tank of gas and if I squeezed 40 MPG out of it (not my best record but tough for me to achieve on my commute).

I drove over the scale where I take my aluminum cans for recycling. The Excursion went over the scale at 7900# with less than 3/4 of a tank of fuel. LOL! At least it's lighter than the bus was.

Does make my ton miles per gallon better than our Focus. :D

Oh, Ok. I'd take Rusty up there then, but he's recently been put back on the road. Not sure I'm ready to take my chances on a long haul with him.

-Jay

My Jeep Liberty CRD went over the scales at 4550#...on the highway (100%) I can get 28+...What would be my TMPG at 28mpg?

According to the calculator it it is 63.7 TMPG

Not sure if you guys saw the results of the 2nd one or not: https://www.icerace.com/amec-2008-economy-2.html

The first one was for fun before a picnic, the 2nd one brought out some hardcore drivers. The Prius and the diesel had over 100 ton mpg.

That Avenger that won last time at 48MPG I was sure was a filling fluke but he got 50MPG this time, so that's amazing, he needs to start a gaslog.

As for the route, it's sweeping curves with lots of ups and downs in the Adirondacks. The only lights are at the end we pass a stretch of 6 or so in 1-2 miles. That sucked. But there was also a section of probably almost 30 miles all with either a steady or slight downgrade. I'm sure most didn't have their engines on for a long time.

I rode with my friend in his RX7, we got the worst MPG and the fastest course time! But mostly we tuned up his MegaSquirt a bit and had a fun time. It's really funny because I have a Festiva that can average 50MPG and he has an CRX HF (as well as a VX) that easily pulls 55MPG and we probably could have gotten really close to the 65MPG needed to win.

A measure of efficiency commonly used in the aerospace industry is "seat miles per gallon". I think to factor in weight, we need to compare "actual payload-mile/gallon".

i.e. examples:

If you drive a 5800# SUV, get 13 mpg, and normally drive by yourself at say 200#, thats 2600 payload-lb-miles/gallon. Weight of vehicle shouldn't matter, it's the weight of the payload carried that matters. On the other hand, if you filled all 9 seats with 220# passengers, and manage 12 mpg, you get 23,760 payload-lb-miles/gallon.

A motorcycle at 70 mpg with a 170# rider would be 11,900 payload-lb-miles/gallon.

A 12 passenger Dodge Sprinter Diesel full of 200# passengers at 26 mpg would net 62,400 payload-lb-miles/gallon.

just my .02 :)