xkimsungminx

iTrader: (2)

oh and all you guys that're getting like mid 30's mpg, about how fast do you drive on the freeway?? cuz just this weekend i sorta did alot of driving?? i guess, well i have 135 miles on it... and it's like 1 hash mark above the half point on the gas gauge =|, i feel like my car just gets crap mileage for some reason, and i did do mostly highway miles this weekend too so i dont know man eff

xkimsungminx

iTrader: (2)

sorry for 3 posts in a row but a question to those who get crazy mileage... do you guys have rims?? or are you guys on stock wheels/tires? cuz having rims makes a difference in the mileage especially if you're on 205/40/17 profile tires cuz the circumfrence of the tire is smaller than stock tires so your tire gets a full rotation faster than stocks, causing your mileage gauge to be incorrect, i think i read that somewhere on a post about wheel sizes etc. about the % error you'll have in your mileage when getting rims and tires

Mustang5.0HO

gas by my house is at 2.55 and I live in cali

Jrfish007

iTrader: (3)

Rims play a roll in milage, about 3-5MPG. Different tire can even affect it, for instance sticky tires that grab well will give you worse milage because there is more rolling resistance versus hard highmilage tires. The rims and tire also have a MUCH larger rotational weight now, even if your new rims are lgither, you've moved the weight further from the center, so now the motor most work harder to turn the rims/tires, wierd concept but it's true. If you want really good Milage, get HX or even hybrid rims, they are light and small rims.

Jrfish007

iTrader: (3)

just FYI, when I had my 17's on my old 7thgen, I notice about a 3 MPG drop, but I drive 50% city and larger rims are bad for stop and go, that's where I lost most of my milage.

xkimsungminx

iTrader: (2)

hm.. okay, so if i get rims i can expect the mileage to be a little off because the total circumference of the wheel is gona be smaller than my stock wheels? i know that weight makes a difference in mileage and stuff, but doesnt the wheels being smaller or bigger make a difference too? cuz your mileage is gauged by how many rotations get clocked, and if you were to have a slightly smaller total circumference, it'll rotate more often so it'll say you're getting more miles than you really are.. correct?? or am i wrong?? i'm not sure, so if someone could enlighten me about this

ncirom2003

iTrader: (7)

**** i hate you guys, i got 25-29 city mpg last few times i did it. ill have to start trying to baby her and do this again.

Mustang5.0HO

rims play a BIG role ...i should know

Jrfish007

iTrader: (3)

Well, it's kind of complex, because a smaller overall diameter means you will have less distance covered by the tire, that is correct. Now if that is good or bad is a different story. For the city, that is good, becuase now the car doesn't have to work as hard to get moving, that is countered by the fact that the weight is further out (this is called raising the moment of interia, this is bad for city driving), so you have a plus and a minus, which way it goes I don't know with out knowing the moment of interia of you specific rim/tire and a few other things.

So city is between good and bad, not sure where; but highway is bad, because now you have a higher moment of interia, so the car has to work more to keep the same speed, and the RPM's are higher so you're engine is working faster hence burnign more gas (that short for a long story of why).

Now there are many other things that drag into this, and that is why I can not say more than my personal experience and that this CAN affect your MPG. Reason is because there are things like air drag and bunch of other things I couldn't begin it predict that can affect your MPG, you would almost need a degree in applied physics to calcualte the exact drop or increase. I do know that sticky tires and wider tires are a big player, I've noticed that first hand.

if you want good MPG, you should have hard skinny tires.

Blackpearl

Here are my pictures about how the milage is showing up and the gas guage indicator moves.
I always use the trip B (~Benzen) to count the miles on a tank of gas. I reset every time I fil up.

lxcivic2k1

Right now all I can get is 36ish and around 370 miles but I'm on 17s(correct tire size) and Magnaflow Exhaust. So I'm not doin so bad sinc it would be a lil closer to 39 with steelies.

gearbox

iTrader: (95)

i get 15mpg if i actually drive the car (pressing gas hard).

Ratz-2004

I get 27.........is that bad?? i have an 02 ex(auto).....what can i do to bring it up? i drive concience (most of the time) he he......... is 27 normal??? im reading all these 37 and 40 mpg and wondering why i cant get that?

gearbox

iTrader: (95)

you have to drive almost 100% highway miles to get that high. usually in the city i get around 22-26mpg.

lxcivic2k1

32 is my normal with city but then again a don't get above like 4k so that might be why.

I also noticed that at 80 its at 3500 where auto is at 70 at 3500 so that might also be helping me a lil

gearbox

iTrader: (95)

my auto is at 70 at 3000

Blackpearl

Probably I get high milage becouse I try not to push hard. I shift up at 2500 (if you have more wheigh than at higher rpm). All iz about the load on the engen rather then the rpm. After some time you fil where is the shifting point. Try to avoid as much as possible the break. My car never see higher than 3000-3200 excep when I pass. I obey the speed limits, and I lower the speed a litle bit if I am not disturbing the trafic. My race is for gas saving and for environment. This give you the same satisfaction as high speed race.

acidbaby

iTrader: (15)

i get around 320 miles per tank

acidbaby

iTrader: (15)

how is that possible?

turboengnr

iTrader: (2)

get this......

my parents went on a trip from here (lancaster Ca.) to Reno NV in their 99 vette. They got an average of 38 mpg.

90mph in 6th gear somewhere between 2300-2500 rpm.

Jrfish007

iTrader: (3)

vets have a very low coef. of drag, little wind resistance and lots of torque, so low RPM's for the engine, specially with a 6 speed.

ncirom2003

iTrader: (7)

i highly doubt that, its 500 miles and the needle isnt even in the red so he still has a gallon or two.

xkimsungminx

iTrader: (2)

maybe he has a smaller size wheel diameter than the stock diameter, if that's the case, it might make sense?? haha i dont know

DDragon7

Could also be that he didnt reset the OD on the last fill up.

Ratz-2004

yeah i like that one.....you do need to reset it....he he
i get to like 320 and im searching for a gas station......
and i have tried both....i have an auto but it seems that wiehter im
slamming the gas or not i still get about 27-28 mpg.......i went one tank
as slow as possable....slow accel and kept the rpm as low as poss and i still
didnt get over 28 mpg

xkimsungminx

iTrader: (2)

haha good point, i totally forgot to even consider that a possibility, cuz i was assuming people were gona be honest about their mileage ehh

Blackpearl

Well guys. That is not the case (forgeting to reset the trip odometer)(do you guys going to race, and during the race you say: Ohh sh.., I forgot to put nitrous...) ha ha ha. I am also engenier and with PhD so I think I am not that dam. I dont forget to reset it as you don't forget the special things for your car . As I state in this treat, my race is for the MPG, but in not that side that you sacriface the AC, audio etc. Is like the coin with two faces. Race for speed and performance or MPG are just the who faces of the coin. Both can give you satisfaction. I doupt that genting 27 MPG or less will not make your driving less enjoiable. The point is to get satisfaction on driving. That is the point. I know, most of the people here in the forum are on the other side of the coin than me. But that is fine. Actualy is the same coin .
As I mention at #78 in this treat, I try not to push hard.
I have the original Firestone tires, no moods other then iridium spark plugs.
Alway use 87 grade gas. Aditives for cleaning injectors once a year (here in USA, the gas have low sulphur, so no need for cleaning every gas fil up. I need to change the oil (I donk know what is inside of the engen; I bought the car in Aug). At the next oil change the engine will get 5W20 Mobil 1 as presen.

Blackpearl

You are wrong.
Bigger the diameter -> lower the RPM for the same speed -> better MPG

ncirom2003

iTrader: (7)

thats not what he meant. he meant since a smaller tire spins more than a big tire does at 60mph the odometer would think youve driven alot more with a smaller tire.

lol, and you just praised your brilliance

Jrfish007

iTrader: (3)

So let me get this straight, you're an engineer with a PhD and you bought a 4 year old civic and doesn't know how to spell engineer or engine?

BTW, sulfur is not the only thing that clogs injectors and Europe has FAR lower sulfur in their gas than the US, hence the reason they've had direct fuel injection for the last 10 years and the US has not.