Ouch my mileage sure drops at speed

[BUTCH1]

Originally posted by: MercenaryForHire

Originally posted by: BUTCH1
Your right, the calculator specified the radius not the diameter. Using the radius it comes out to 101.5 MPH, still way too high. Oh well, Guess I'll just take the OP's word for it, looks like a nice little car BTW...

You're still smoking rock. I get 74.2mph from those numbers - which is perfectly plausible that the OP would see 68 given speedo error + wind resistance + margin of error.

Originally posted by: mugs
My Civic (2003) would be at ~3400 RPM at 68 mph in 5th gear. It's almost exactly 20 mph per 1000 RPM in 5th gear.

What tires are you on? 3400 in 5th would put me around 80mph.

- M4H

Hey M4h, my post says "numbers still too high", pull the crack pipe out of your a$$
and lose your attitude..

 

[IAteYourMother]

Originally posted by: iamaelephant

Originally posted by: KingofCamelot

Originally posted by: iamaelephant

Originally posted by: Scouzer
Actually, the thoughts in my mind was using archaic units to please stupid Americans.

I almost typed "stupid" but decided I'm sick of being banned Some Americans are sensitive to having their wittle feewings hurt I've found.

Yup, us stupid Americans with our archaic systems.

Hows that constitutional monarchy working out for you two? The Queen doing well today?

As Scouzer said, the Queen holds absolutely no power over here. You don't know anything about my country :roll: Just start using the metric system you imbeciles.

Seems like you're sensitive to having your wittle feewings hurt.

It was a joke.

 

[PlatinumGold]

Originally posted by: BUTCH1

Originally posted by: MercenaryForHire

Originally posted by: BUTCH1
Your right, the calculator specified the radius not the diameter. Using the radius it comes out to 101.5 MPH, still way too high. Oh well, Guess I'll just take the OP's word for it, looks like a nice little car BTW...

You're still smoking rock. I get 74.2mph from those numbers - which is perfectly plausible that the OP would see 68 given speedo error + wind resistance + margin of error.

Originally posted by: mugs
My Civic (2003) would be at ~3400 RPM at 68 mph in 5th gear. It's almost exactly 20 mph per 1000 RPM in 5th gear.

What tires are you on? 3400 in 5th would put me around 80mph.

- M4H

Hey M4h, my post says "numbers still too high", pull the crack pipe out of your a$$
and lose your attitude..

hmmm, didn't you also post this little bit of wisdon?

Is that CRPM?? (Canada's RPM)..No modern vehicle will turn 2700@68 MPH unless it's been modified for racing and no
auto will get WORSE MPG @ cruising speed than in traffic (except hybrids of course) please, drag your owners manuel
into the crapper and read it before any more posting, you lack the automotive knowledge that a 10 year old in the USA
takes for granted, making YOU look stupid..

so, the OP was probably right about 68 mph @ 6800 rpm, but his reading of his gas mileage meter was way off and lacked understanding of how it works.

 

[DanTMWTMP]

I wish the US will someday use the goddamn metric system. It just makes a lot more sense. We need to get w/ the world and use the standard the rest of the world is using.

 

[mrSHEiK124]

Originally posted by: BUTCH1
Is that CRPM?? (Canada's RPM)..No modern vehicle will turn 2700@68 MPH unless it's been modified for racing and no
auto will get WORSE MPG @ cruising speed than in traffic (except hybrids of course) please, drag your owners manuel
into the crapper and read it before any more posting, you lack the automotive knowledge that a 10 year old in the USA
takes for granted, making YOU look stupid..

Uh, my Altima does around 2400 RPM to keep me at 70 MPH, don't see why he can't be at 2700 RPM with a way smaller engine.

 

[BUTCH1]

Just out of curiosity I might start a "RPM@70MPH" thread when I get home from work tonight.
as for my responses,well if you call americans "stupid" or refer to me as a "crackhead" it just
serves to turn the thread into a giant flame-fest...

 

[Riverhound777]

My Mazda 3 does 3000RPM at 70.

 

[otispunkmeyer]

all the fords i have driven (focus, transit, fiesta, mondeo, galaxy) here have almost always been geared to do 70 in 5th at 3000rpm. yeah i think its a little high as well, but then again in my car the engine hasnt got enough grunt to maintain a good speed in a higher gear. (hell even now wind and a hill will make the car struggle)

i didi drive a 2.2 litre mondeo TDCi and it had 6 gears. i got nearly 55mpg doing 85mph

 

[BUTCH1]

I guess there must be a lot of variation in final drive ratios, My old 95 Escort would
be at 80@3000RPM if you survived the onramp!

 

[Kelemvor]

My car hits its top gear at like 40 mph. I don't know why they don't have a gear up by 60 or so just for freeway driving.

 

[Zenmervolt]

Originally posted by: d33pt
if your 5th gear was higher, you'd need more power to overcome drag, so you'd actually waste more gas.

Wrong. MPG is affected much more by RPM than by throttle position. You're better off at wide open throttle and 1,800 RPM than you are at part throttle and 2,700 RPM from a fuel economy standpoint. From a drivability standpoint, however, it would be an incredibly stupid thing to do to make the engine lug like that.

ZV

 

[Zenmervolt]

Originally posted by: sao123
The national speed limit is still 55 on all non "limited-access" highways... (interstates only make up about 2% of all roads)

Wrong. There is NO "national speed limit" anymore. It's all determined at the state level.

ZV

 

[Zenmervolt]

Originally posted by: BUTCH1
Just out of curiosity I might start a "RPM@70MPH" thread when I get home from work tonight.
as for my responses,well if you call americans "stupid" or refer to me as a "crackhead" it just
serves to turn the thread into a giant flame-fest...

Butch, give it up. The OP is right. Very common for a 4-cylinder car to be spinning 2,500-3,000 RPM at 70 mph. With 68mp at 2,700 RPM and a normal redline (6,250 RPM is a conservative estimate) the car would redline at just over 157 mph in 5th. (Divide 6,250 by 2,700, that gives you the number of times that you need to multiply 2,700 to get to redline, then take that result and multiply it by 68, which gives you 157.4 mph.)

ZV

 

[Zenmervolt]

Originally posted by: BUTCH1
I guess there must be a lot of variation in final drive ratios, My old 95 Escort would
be at 80@3000RPM if you survived the onramp!

80 mph at 3,000 RPM would yield a speed of 72 mph at 2,700 RPM. Shockingly consistant with the OP.

ZV

 

[SampSon]

31mpg-42mpg is great.

 

[BUTCH1]

Originally posted by: Zenmervolt

Originally posted by: BUTCH1
I guess there must be a lot of variation in final drive ratios, My old 95 Escort would
be at 80@3000RPM if you survived the onramp!

80 mph at 3,000 RPM would yield a speed of 72 mph at 2,700 RPM. Shockingly consistant with the OP.

ZV

Well I was wrong, his 3.91 final drive ratio probably pushed it up a little higher than
a non GT version of the car so might be a few extra rev's @ Hyw. speeds but gains
better acceleration. I checked mine on the way home tonight, turning 1900@ 70 but
thats a V-6 Malibu geared for a quiet ride..

 

[b0mbrman]

Originally posted by: sao123

Originally posted by: Scouzer
Car: 2006 Pontiac Pursuit GT

I have an on board fuel economy gauge. It is very accurate. I have tested it on two fuel tanks in the past, and it was within .2 mpg of my calculations.

When I was driving through the city, the speed limit was between 44 and 56mph (converted from KMPH). In about 20 miles of driving with this, including three red lights (complete stops) and numerous times speeding up and slowing down, I managed 42mpg.

After this, I finally got out on to the open highway where the speed limit is 68mph. I turned on the cruise control at exactly 68mph, and watched the fuel economy. Over the next two hours my economy dropped and averaged at 31mpg.

Ouch. Sucks. And it happens every time.

Why don't they make 5th gear higher? My car turns at about 2700rpm to maintain 68mph, seems higher than necessary...

Several fuel economists suggested that they make 6th gear which would run at 65mph at 1800rpms thus making fuel economy peak at 65 instead of 55... but thent he government claimed that would encourage people to drive 65mph all the time thus creating a more sufficient speeding problem...
:thumbsdown:

Interesting.

Links?

 

[b0mbrman]

Originally posted by: BUTCH1
Just out of curiosity I might start a "RPM@70MPH" thread when I get home from work tonight.
as for my responses,well if you call americans "stupid" or refer to me as a "crackhead" it just
serves to turn the thread into a giant flame-fest...

Calling Americans stupid is business as usual.

You making unfounded claims and insulting people in the process is what's turning the thread into a giant flame-fest

 

[Tommouse]

I can attest to drag killing gas mileage (not like you needed more proof anyways ). When my car is clean and waxed I get around 32mpg on the highway. When its all dirty and nasty it gets 29-30. This is at speeds or 75-85.

 

[Mallow]

Originally posted by: KingofCamelot

Originally posted by: iamaelephant

Originally posted by: Scouzer
Actually, the thoughts in my mind was using archaic units to please stupid Americans.

I almost typed "stupid" but decided I'm sick of being banned Some Americans are sensitive to having their wittle feewings hurt I've found.

Yup, us stupid Americans with our archaic systems.

Hows that constitutional monarchy working out for you two? The Queen doing well today?

the queen is an essential part of the system! haha, yeah right!