Speeds for best gas mileage
#1
Junior Member
Thread Starter
Join Date: Dec 2005
Location: Winnipeg
Posts: 7
Likes: 0
Received 0 Likes
on
0 Posts
Speeds for best gas mileage
With gasoline prices being what they are, I wonder if anyone has tinkered with various speeds to see at what speeds would one get the best fuel economy (everything else being equal). I have a 1997 Bonneville with a 3800 Series II from an " '01 or '02 Buick LeSabre" and I assume the transmission is obvious & ubiquitous (that there are a million identical or nearly-identical engine / transmission combo'* out there).
Is this a simple matter of lower RPM'* are better? I know it gets better gas mileage at 55 mph or 90 KM/h than at 62 or 63 mph (100 KM/h is 62.5 mph) but I am not going to do 85 KM/H for 2 hours just to try it out: I'm hoping someone else has!
Related, I hope: I have found best gas mileage after several (4-5) consecutive tanks of 92 Octane gasohol, and if you want to point out that makes no sense, save your breath / keystrokes, I already know that. But it works. 94 Octane gasohol with octane boost and it goes down to about the same as 90 Octane gasohol. By gasohol I mean (E= <10%) or that it'* ethanol blend, not more than 10% ethanol. FWIW the octane boost was NOS with a touch of nitromethane in it. I also constantly use what *I* call "MoleKule mix" also called "the brew" or MBF (MolaKule Brew Fuel???) A FINE gent (MoleKule) on another board (abbreviated "BITOG") is a chemist or something with secrecy agreements with a few companies. I believe he is legally OK, however, JUST saying trust me, the best daily-driver mix is 1 part Schaeffer'* Neutra to 3 parts FP (Fuel Power) and add 1 oz. per five gallons. And ask him nothing of how or why.
What'* the state of those instant fuel-consumption meters? I'm thinking something more than a vacuum guage; I heard about that one 20 years ago.
Is there a point to cranking up nominal timing? Having a "summer thermostat"
I want to drive to beaches LOTS in the next 2-3 months and I know going over 100 KM/h really guzzles.
Thankyou very much in advance
Rob in Winnipeg
Is this a simple matter of lower RPM'* are better? I know it gets better gas mileage at 55 mph or 90 KM/h than at 62 or 63 mph (100 KM/h is 62.5 mph) but I am not going to do 85 KM/H for 2 hours just to try it out: I'm hoping someone else has!
Related, I hope: I have found best gas mileage after several (4-5) consecutive tanks of 92 Octane gasohol, and if you want to point out that makes no sense, save your breath / keystrokes, I already know that. But it works. 94 Octane gasohol with octane boost and it goes down to about the same as 90 Octane gasohol. By gasohol I mean (E= <10%) or that it'* ethanol blend, not more than 10% ethanol. FWIW the octane boost was NOS with a touch of nitromethane in it. I also constantly use what *I* call "MoleKule mix" also called "the brew" or MBF (MolaKule Brew Fuel???) A FINE gent (MoleKule) on another board (abbreviated "BITOG") is a chemist or something with secrecy agreements with a few companies. I believe he is legally OK, however, JUST saying trust me, the best daily-driver mix is 1 part Schaeffer'* Neutra to 3 parts FP (Fuel Power) and add 1 oz. per five gallons. And ask him nothing of how or why.
What'* the state of those instant fuel-consumption meters? I'm thinking something more than a vacuum guage; I heard about that one 20 years ago.
Is there a point to cranking up nominal timing? Having a "summer thermostat"
I want to drive to beaches LOTS in the next 2-3 months and I know going over 100 KM/h really guzzles.
Thankyou very much in advance
Rob in Winnipeg
#2
Senior Member
True Car Nut
120kmh I get the best economy that should be 75mph. I get about 29mpg with the ssei and 31mpg with the olds.
at 130kmh or or 80mph i get about 28 with the ssei.
have you replaced your o2 sensor and cat?
oh i also should add the olds has the grany gear trans of 2.84 so it will get 30 at several highway speeds.
at 130kmh or or 80mph i get about 28 with the ssei.
have you replaced your o2 sensor and cat?
oh i also should add the olds has the grany gear trans of 2.84 so it will get 30 at several highway speeds.
#3
Senior Member
Posts like a Turbo
Join Date: Feb 2006
Posts: 220
Likes: 0
Received 0 Likes
on
0 Posts
I just finshed a 800 mile round trip through the NC mountains, with a full load of people on board. I averaged around 27 MPG, and I generally ran around 70 MPH. If I had ran around 60 MPH, I am sure I could have hit 30 MPG. I would say the best "trade-off" (speed vs. MPG) speed would be 65 MPH for me.
NCC
NCC
#4
Guest
Posts: n/a
I have pulled a dead on 32 @ 75 mph... I have done 29-30 at a bit over 80 after that it really starts to fall...
I usually just set the cruise at 75-76 and go along my merry way
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote
I usually just set the cruise at 75-76 and go along my merry way
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote
#5
Junior Member
Posts like a Ricer Type-R
I've pulled 31 with my 93, and 30 with the 95. It'* quite possible to get that in any car on the Forum.
Buick_Engine, can you put your year and trim level in your signature?
Buick_Engine, can you put your year and trim level in your signature?
#6
Senior Member
Certified Car Nut
Join Date: Oct 2002
Posts: 11,308
Likes: 0
Received 0 Likes
on
0 Posts
At an avg. speed (cruise control doesn't work) of 110kmh (70mph) with highway and (35mph) city driving I get around 26-27mpg.
Last weekend on a 300 mile highway trip home at an avg. speed of 100kmh (60mph) @ 1900-2000rpms I got 33mpg - 480km on exactly half a tank.
Last weekend on a 300 mile highway trip home at an avg. speed of 100kmh (60mph) @ 1900-2000rpms I got 33mpg - 480km on exactly half a tank.
#7
Administratus Emeritus
Certified Car Nut
Originally Posted by willwren
I've pulled 31 with my 93, and 30 with the 95. It'* quite possible to get that in any car on the Forum.
Buick_Engine, can you put your year and trim level in your signature?
Buick_Engine, can you put your year and trim level in your signature?
#10
Guest
Posts: n/a
You both have some issue then...
The rating for the 92 SSEi was 17 cty and 25 hwy, But real world usually netted a couple more than that...
If the 94 SLE is SC'd then it should do about 18 cty and 26-27 hwy... If its an L27 it should be rated for 18 cty and 28 hwy...
Even in my old beater 91 LE I have done over 30 on the road...
My worst in both is usually 18, and I have to make it work for that low number
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote
The rating for the 92 SSEi was 17 cty and 25 hwy, But real world usually netted a couple more than that...
If the 94 SLE is SC'd then it should do about 18 cty and 26-27 hwy... If its an L27 it should be rated for 18 cty and 28 hwy...
Even in my old beater 91 LE I have done over 30 on the road...
My worst in both is usually 18, and I have to make it work for that low number
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote