getakey

Have you guys seen this site before:
http://www.fuelly.com/car/acura/rl

You can select any car

Ballinger

People are reporting some pretty high MPG for various cars.

getakey

I was on another forum (boating) and I guy claimed that he got 30+ mpg in his vette cruising at 80 to 85. I could not believe that, but looked up a vette forum and multiple owners saying the same thing.

Ken1997TL

I believe it, lots of torque with a super tall gear giving you LOW rpms.

HEAVY_RL

iTrader: (1)

Those RL numbers look legit.

Ballinger

The best number are "mileage on the tank", rather than mileage while actually cruising. Heck, I get 30+ mpg at 80mph, every single morning in my commute and for several miles. The, I have to climb a big hill and drive in city traffic.

I'm at 19.7mpg on the tank today, with less than a gallon left in it. This is better than average for me.

getakey

I agree. I get about the same ave mpg (19.7), but I've never seen 30 mpg on the instant mpg going 80 unless it was downhill. On a totally flat road at 80, I'm lucky to get 23. Not complaining, just that's what it is.

The vette guy claimed speed control set at 80 (rpm = 2200) and his trip ave was 31mpg. Understand that those cars are light and those V8s have great low end torque, but still seems a bit of a stretch. (He is from TX)

alex1372

I have cool little app on my iphone - Gas Cubby; takes a minute to fill the info. For the last 5 months I average 21MPG according to statistics making 330-350 miles per week per fill-up, but computer in the car tells me over 22MPGs... Driving in tight traffic on expressway 40 to 70MPH

037

the car should also be taking into account idle time which I dunno if your app does. I'd go w/ what the car says as I will have a heart attack if it's any lower.

getakey

mpg calc is easy
how many miles did you go since last fill-up divided by how many gallons to fill
nothing to do with idle time. I'm sure the phone app just has him enter mileage at each fill-up and gallons purchased

the car calculator is probably based on total gas through injection system. Not sure how accurate that is.

037

sounds like someone who doesn't have an RL.

if you had one you would notice your MPG go to hell whenever you were standing around.

oo7spy

What does it matter if he has an RL or not? It's not rocket science. Fill up. Drive x miles. Fill back up with y gallons. Avg mpg = x/y. For any car ever created this will be true. The only variant to consider is that filling up might not be accurate to +- 1-2%. Even so that is the most accurate way to calculate. My car always tells me 22+ mpg, but I calculate 21+. The car is close, but not accurate. No matter what car he drives, a 7th grader with a calculator could tell you avg mpg.

wackjum

What's with your preoccupation with idle time? What ultimately matters is the mileage you get out of a certain amount of fuel in your normal driving. The instantaneous mileage calculation you get is useless. Coasting down a hill will give you an instantaneous reading comparable to the best hybrids. Conversely if you are at a red light, your instantaneous miles per gallon is exactly zero. But surely you get more than zero miles per tank.



I always write my miles down on the receipt I get from the pump. Afterwards, I either reset my trip meter, or in the case of the RL, it does that automatically.

merlin the wrench

we made a trip from Sacramento to Monterey CA last month for a conference. The tires were Michelin and inflated to 32psi cold all the way around. I thought the first tank was a fluke since we averaged about 27 cross country last year with some General tires. 44 MPG going to Monterey and 35 coming home. Round trip about 38 - 39 MPG 2006 RL 65 - 70 mph taking it easy with two people and luggage in the car.

Around town to and from work stop and go on Fwy is usually 18.5 - 20.5 with Chevron being lower than Shell. Tank added before Monterey was 94 octane Shell.

Ballinger

That's outstanding mileage, Merlin! The hottest gas I can buy w/o going $6/gallon is 91 octane and my best "tank" is just under 25mpg for a day driving from San Diego to Las Vegas, not all highway.

To the other discussion, "Idle Time" does matter in an RL --- for our running average MPG. When the tank is done, the final number is still computed by (number of gallons burned/miles driven) but mid-tank, the car monitors gas being burned even while the car stands still. Yesterday, I filled up on my very nearly empty 19.7mpg tank (over $70, thank you) and drove home. Sitting at a stoplight I had coasted to with 25.4mpg on the average meter, I sat and watched it drop to 24.8 while I waited for green. This is because the car's burning gas, the computer is monitoring consumption and updates the (consumed/miles) results even if the car isn't moving. Of course, the relative effect was more pronounced on a tank with only a gallon of air space, ie "early in the tank".

Now today, my goal is to drive the ramps like a grandpa and, still using the speed control at 80, get the average ticker to read 27.7 by the time I hit the bottom of the hill.

EL19

iTrader: (4)

With mixed driving I get 21.5 MPG. I took the RL on a trip to dover with it being 90% highway and averaged 28mpg with 4 people and luggage. I was happy about that LOL

getakey

not sure what you are getting at
I am origianl owner of 2005 RL and now have 128K miles on it. Think I'm pretty qualified on any RL topic, but mpg has nothing to do with any model of car. Sitting idle you get Zero mpg. Coasting downhill you get lots of mpg. What matters is how many miles you have driven and how many gallons you consume.

getakey

Where do you get 94 octane in CA?

037

why would anyone use instant mpg? I'm talking about pump to pump average mpg.

sitting idle is negative mpg btw cause you're eating fuel and going nowhere.

getakey

You were the one that brought up idling.
I am talking pump to pump. Miles travelled/gallons filled.
That is pump to pump.

FYI - no such thing as negative mpg. Its Zero mpg at idle.

EL19

iTrader: (4)

I think by negative mpg hes talking about the fact that you are going nowhere yet still burning gas. Which will bring down your mpg if that was calculated into it. But yes, it is zero mpg because you are getting zero miles per gallon.

037

so...you've idled through 5 gallons, went 0 miles.

still paying for 5 gallons aka negative mpg

getakey

maybe you should punch in 0/5 on your calculator and see what happens

037

to be fair, I've made up that term to make convo easier, I guess that backfired.

either way...you get the point, end of story.

P.S. I fixed the part where my math was not mathematically correct. end of story...again.

Ballinger

Oh, drive your car 18 miles in reverse and you'll find that the RL actually puts a gallon of gas into the tank. I do this all the time when I'm running low on funds. Yeah, it steers like a forklift but, whatever.

Dudes. Idling burns gas. Burning gas counts toward your mpg on the tank. Fini', no?

getakey

I think we've beat a dead horse here.

I'm still wondering how Merlin got 44mpg. I want what that car's been drinking.

oo7spy

Finished. (Hopefully) As long as no one here thinks you can go a negative distance this IS finished. If you do, we can have a science discussion in a different forum.

Getting back to the topic, I cruised @ 80 today on flat highway and the instant "block" was on 20 mpg. Now, understanding that these blocks represent 2 mpg each, my average was steadily climbing from the 20.8 it had when I left home. By the rate it was climbing, I think the actual instant mpg would have to have been over 22 mpg. This just goes to show that the instant MPG is inaccurate and unreliable at any given instance. Not only is it only able to guess your instant mpg to within +- 1 mpg (terrible resolution), it obviously was reading low today when I looked at it.

With all of this in mind, the corvette, if it has the exact same system as the RL, could have actually been getting 27-28 mpg. The only true way to tell is to fill up, drive 80 to the next gas station and fill up again.

And one more thing getakey, what does being from Texas have to do with his estimate? Everything is bigger here, but that doesn't mean our exaggerations or mpg numbers are too. J/K

merlin the wrench

The shell at Sunrise and Greenback in Sacramento is the one that had 94 octane. Usually we get 91 as that is all we see around town. We have found that the gas from that shell usually gives us better mileage than the Chevron near us. Sometimes the Chevron gas locally will be off 10% on all our cars about the same time making me think someone is diluting the alcohol in it with water. Central Valley gasoline south of Tracy along I-5 gives us better mileage too compared to most local stations here in Sacramento. I keep a spreadsheet for every purchase of gas and use an excel formula to figure mileage. Usually when one tank is way good it means I screwed up filling the tank but on the trip to Monterey and back the mileage was consistent over 2 tankfuls so I know it was real. I am guessing that with the higher octane the engine timing advanced and got the last little bit of energy out of the gas. Funny thing is that Shell usually has 91 octane but lately it has been showing 94. Something changed in their formula at that station. We love it cause with the R+M/2 formula that is almost 100 Octane the way it used to be figured.

oo7spy

Not being from CA, I was going to guess it's an all downhill drive, but no. Monterrey elevation = 26 ft, Sacramento elevation = 25 ft. I use 93 octane and the highest I have ever seen is 28 mpg after and oil change. 44 is crazy. That's some Texas size mpgs.

037

maybe the roads are all even for 44mpg...my 20mph on summer tires comes from all hill driving constantly up and down never even.

I know this cause I was looking for a place to measure 0-60 and couldn't find 200ft even space in 77mi commute.

getakey

I've lived in TX, so I know that there are some stories to be told
I agree that instant may not be spot on, but I suspect it is fairly close in the +- 1mpg as you suggest.
I've looked at the instant in the Trip Computer going a variety of speeds on an absolutely flat highway. With speed control on, I see 25/26 mpg at 75mph. It goes down from there at any constant speed above that.

The vette guy claims mpg calced with fill-up. Its interesting that he says his V8 was clocking 2200 rpm at 80. I would have thought lower as I see about 2300 rpm at 80 in my RL. Wonder what the 6speed does in the 2011.

Our car is about 1000 lbs heavier, probably a bigger COD, and also has the SHAWD.

merlin the wrench

Sacramento to Tracy area is a drop of maybe 20' then along I-5 which is flat and minor hills paralleling the foothills, then up and over the coastal range at Pacheco Pass at 1,300' and then back down to sea level. We just drove really easy and never sped up or slowed down much as it was mostly freeway. I would say we did 65mph most of the way in very light traffic.

Ballinger

Also: tires and pressure affect things.

Por ejemplo, my mileage data comes off of oem MXM's with 35psi all around. When I get mah dubs, the numbers will likely change even if I drive the same.

wall e

how are u guys getting higher numbers than the EPA gas ratio. For ex. the 2009 RL is 16/22 and u guys are waaay above 22.

oo7spy

EPA just doesn't want to admit a car can be so sexy and full efficient at the same time.

sherman_nguyen

I usually get around 18mpg for local but when my RL gets on the freeway it is a gas saver. I usually time the mpg when i cruise at 65mph about 60 miles from San Fernando valley to San Bernardino, CA and i got around 34 mpg which is the highest I could get on my RL. So 44mpg is plausible i guess.

alex1372

The car does take idle time into account, however readings from car computer are always higher than calculator... Go figure

As for math exercises, +1 with you - you still have to pay even you're just sitting and burning gas, so it is negative (in the packet)

wall e

Im a math major, and distance is never negative, which is why u take the distance formula contains an absolute value symbol.

Legendliving

That was news to me that the car computer isn't accurate? Don't know if the options are the same as on my European car, but I have a tripA and tripB option and I spend far too much time trying to get the numbers up. I have done about 30k miles since I bought the car last May and converted to US gallons I've had 24.6 over those 30k and 24.5 since the last service. It is mainly on the highway with cruise set at 64 with a once a day overtaking blast so I can hear the nice noise the engine makes which is only audible over 4000 revs.

oo7spy

Those mpgs sounds right. Our systems are the same across the pond with both A and B trips. I wasn't saying the computed average was way off, but rather, it reads a little higher than the fill and calculate method (at least in my car). There will be some error no matter how you calculate it unless you fill up to EXACTLY the same amount every time. It is just a matter of which method has the least error. I think the computer's method isn't accurate enough to display tenths of mpgs (significant figures), but I also don't do that when I calculate at the pump. I round to the nearest integer or possibly to the nearest half and go with that.

*correction to previous post: *fuel* efficient, not full efficient. Damn you iPhone autocorrect!