[Gtholic]

I tend to drive my Opel GT like a maniac. I think this car invites to it, and is the same with most petrol turbocharged cars. I like to feel the push when the turbo kicks in at 3500 rpm and for then my speed is already 150 km/h minimum so pretty soon I am surpassing 200 and don't even notice except because I am passing other cars like if they were stopped at the side of the highway. The only thing I can't pass is a gas station. In fact my fuel economy indicator reads 12 L/100km (19.6mpg) which is a bit too much, specially with fuel prices here in Europe. (about 1.25€/liter, 1.1 at low cost gas stations)

So today I tried and made the effort of driving economically. 5th gear, 90-100 km/h. 2000 rpm or even less... It was exhausting but the average comsuption after a 60 km trip mostly by road was 7.7 l/100 (30.9mpg) according to Car Scanner ELM OBD2 (previously calibrated) which I think is pretty good for a car this powerful, with 90,000 km and 12 years old.

So what kind of mileage do you get from your cars be it turbo or atmospheric, and how do you drive it?

 

[JohnWR]

My turbo and my NA average about the same mileage, at approximately 25 MPG.

 

[Robert Neighbours]

i just drive mine till it is close to empty then fill it up.
i didn't buy my sky for fuel economy.premium gas costs here
in canada about $1.30-$1.40 canadian dollars per litre.

 

[Gtholic]

i just drive mine till it is close to empty then fill it up.
i didn't buy my sky for fuel economy.premium gas costs here
in canada about $1.30-$1.40 canadian dollars per litre.

Premium gas is the same as 95 octane gas i guess?

 

[mikeyt]

In my part of Canada (Ontario) we have 87, 89 & 91 octane fuel with a few stations having 93/94 octane. My Sky runs just fine on 91 from 'top tier' vendors.

 

[Wnolte1122]

In some areas in Wisconsin there are choices in Premium Unleaded. One choice is with alcohol, the other is without...... the price for without alcohol is often .60 cents a gallon more expensive. I gladly pay the premium because I prefer alcohol in my cocktails 🍸, not in my fuel ⛽. 😎

 

[Gtholic]

Such a viariety... Here in Spain there is only 95 and 98 octane. Now I use 95 as recommended in the manual. Will have to use 98 octane if I someday tune my engine to get moar powa though.

 

[rjgramps]

i just drive mine till it is close to empty then fill it up.

Like most vehicles, the primary electric fuel pump in the Sky's fuel tank will last longer if allowed to run "cooler" during it's life span. So if you drive to almost empty, the fuel pump is physically above the fuel line, hence the fuel is not externally cooling the pump. The general rule for any vehicle with a fuel pump in the tank is to avoid going below the 1/4 fuel mark. It doesn't mean you are doing damage when driving with less fuel. It's all about increasing longevity.

The bright side of the Sky and Solstice, it's much easier to replace the fuel pump. Just remove your trunk carpet to access it.

Another related tip.....

If your Sky or other vehicle is disabled for unknown reasons, turn the ignition off and on again and listen for that 5 second buzzing sound from the fuel pump. If you don't hear it, the fuel pump could be your problem. Slapping the underside of the fuel tank (top side of Sky/Solstice) often wakes up the fuel pump. It is most effective while someone else is turning over the engine. This does not repair the fuel pump. It just gets you going until you turn off the ignition. Repeated cycles gets harder and harder, so get to a repair shop or home-done repair right away.

I have helped a few disabled people over the years in parking lots....if no fuel pump buss, slap the underside of their fuel tank while they are cranking the engine. Whola! they are so happy. I tell them...."Don't turn off your engine. Go directly to a repair shop or plan on calling a tow truck when you turn off the engine at your next stop".

 

[wspohn]

We are juggling different octane systems when speaking of Europe.

Locally I get premium 94 octane with no alcohol. That is the equivalent of 98 Euro RON.

Many areas in the US top out at 91 and have added ETOH. As mine is tuned for the higher non ethanol fuel I light foot it a bit when in the US, although I expect that the engine programming will compensate.

 

[ConeHugger01]

My opinion is that when I am driving my "fun" cars (Sky, Trans Am) I don't care any more about mileage. I drive them for pleasure/fun/racing. It's "Smiles Per Gallon". I have a Honda that gets 34-42mpg US for commuting and long trips (A Fit/Jazz, that has more interior room than most SUV's). Though, I do want to change to electric some day, gas won't last forever.

 

[JohnWR]

Today, 87 Octane is $2.18 per US Gallon, 89 is $2.48, and 91 is $2.98.
My NA runs perfectly (no loss of power, no knock retard, and no change in economy) on 87, and my un-tuned turbo does equally well on 89.

 

[wspohn]

John, is there any retard on the turbo car at full boost? IIRC they recommended 91 for that.

 

[JohnWR]

John, is there any retard on the turbo car at full boost? IIRC they recommended 91 for that.

Not in any of the testing I have done, but I clearly haven't tested every possible combination of conditions.
There may be some extremes of temperature, humidity, elevation, etc that will result in a loss of power, but I have not personally found them.

 

[rjgramps]

My turbo and my NA average about the same mileage, at approximately 25 MPG.

If my memory is correct, the actual fuel economy figures issued by GM rate the Redline 1 mpg better. I also recall the automatic being 1 mpg better than the manual transmission. Maybe my memory is incorrect.

 

[JohnWR]

If my memory is correct, the actual fuel economy figures issued by GM rate the Redline 1 mpg better. I also recall the automatic being 1 mpg better than the manual transmission. Maybe my memory is incorrect.

The RL will get better mileage on the highway (I see 32 vs 28) so the EPA drive cycle will show better average economy for it. My real-world driving gives me approximately the same mileage for the two. I also do not consider 1 MPG to be a significant enough difference to comment on, since it is less than the deviation I can get from one day to another.

 

[BlueRL]

When I bought my XKE I asked the seller what the fuel mileage was. His answer was, "I just fill it up when its empty and have fun driving it." Since then, that has been my attitude. Fuel costs are not your major costs, depreciation is. So use it up before it depreciates and enjoy owning it till it craters.

 

[JohnWR]

I suppose that interest in fuel mileage can take many forms, up to and including obsession, and can do so for many reasons.

I am an engineer and really like data. Partly just for the sake of the data, but also as a means of monitoring the health of whatever I am collecting the data for. Changes in fuel mileage for similar driving can (and have) been an early indicator of engine problems, so i will continue to watch it while I continue to enjoy driving my cars..

 

[wspohn]

It would be interesting to know what the mileage of a GXP was in two situations - driven so that it never entered boost and driven as hard as was legal so it was in boost as much of the time as possible (yes, I have seen some people doing that).

Unboosted it betters the NA but if driven like a maniac I expect that the difference would be quite large. That's one of the nice things about turbo cars - you have that choice.

You can get a similar schizophrenic result with a naturally aspirated car - my elderly Lamborghini had a high rpm V12 engine with 12 Weber throats feeding it. In normal driving it would get high teens per gallon, but opened up aggressively on the open road, it would drop to at or close to single digits. Of course my Chrysler big block with sixpack wasn't far behind, but both cars, driven sanely, were pretty reasonable on gas mileage.

In regard to the XKE a good friend has a series 2 that he converted from twin carb to triple carb and was aghast at how much fuel it sucked when driven sedately. I did a custom conversion on another of my cars, and MG with a straight 6, going from two carbs with crappy fuel distribution to triple carbs with excellent distribution, and actually gained mileage over the stock car at cruising rpm.

 

[The_Ghost]

I average 27-30mpg mixed... Much worse when the air is on at about 17mpg. I've done as well as 42mpg at 75-85mph for a 50 mile trip. But I'm usually around 37mpg on the highway. My car gets its best mileage around 78mph. But that's all to do with my tune.....

 

[rjgramps]

My 1984 Honda Magna V65 motorcycle (V4, 1100cc, 1 carb per cylinder) averaged around 45mpg driving to work and back. I don't know what fuel economy it would get under max throttle. What I do know is that I could hardly hang on. They talk about 0 to 60 mph in "X" seconds. At a stop light in my neighborhood, I was well over 60mph before reaching the other side of the intersection. I never drove anything else that fast in my life and likely never will again.

Here is the bike. I gave up motorcycling in 2001 when my wife was diagnosed with M.S. There is a certain amount of risk one must accept when cycling that I could no longer accept. Cell phones were becoming popular back then so it was the right time to give it up. There have been far too many distracted drivers from texting and such. Our Saturn Sky is our current 4-wheel replacement.....so much safer of a ride.