hebrewhomeboy

I just did the math, from how many miles I got on my last tank, and as it turns out I'm averaging 17 miles per gallon. I know Porsche isn't known for their fuel sippers or anything, but this seems kinda low. I drive my car very gently, very rarely taking it over 4K RPM, and I'd say at least 3/4 of my driving is at 65mph on the highway. My car is in great low mileage condition, and runs like a dream. Is this normal gas mileage for an SC, or does is sound like something's out of whack with my car? And is there anything I can do to get better gas mileage from an SC, other than the typical maintenance? (tires at correct psi, tune up, etc)

flatsixnut

Seems very low to me. I am in the mid to high 20's.
From other threads I have read "some" getting over 30 mpg.

old man neri

You're not lugging the engine are you?

When was your last 'tune up'?

abe

I have an 83SC and I am getting about 22-24 hwy if I am careful. I just past the smog test so I know the engine is tunned. Boy, 30 miles per gal...not with our crappy California gas!
abe

theiceman

i get about 600km to a tank and refill about 75 litres , ca't be bothered to do the math but i am driving a 78 targa.
just did the math , works out to 17.5

sounds like yours is right in the ball park,,if your buying a Porsche for fuel ecomomy .. probabaly got the wrong car .. :-)

Brett San Diego

My 78 is typically right at 17-18 mpg. I've never given it a second thought.

Brett

WitchDoctor

Hey, Ice,

by my calculations, maybe a little off, I've got you at 18.8 miles per US Gallon, 22.6 per Imperial Gallon.

I've got no idea what I'm getting, cause I never know when my tank is full -- I have to fuel up slowly, or the pump quits, like it does when the tank is full. Usually happens about 30 times per fill up, no matter how careful I am. Grrr.

WitchDoctor

I'm sure there are going to be vast differences between a sporty ride on the twisty roads, versus a 5th gear cross-country commute at a stable speed.

It'd be nice to know the max mileage I could get out of the car by such a method, but it wouldn't be really relevant to the way most of us usually drive.

Joseph Mills

Maybe you already do this, but if not you might try it...

After you insert the gas nozzle into your tank, rotate the handle 180 degrees (you hold the handle upside down), and then pump your gas.

Using this method mine fuels up full with no issues at all. You do need to be careful and hold the gas line with your other hand so it doesn't hit your fender and leave a mark.

..

wwest

My '78 Targa gets 20-22 MPH hwy when driven consistently ABOVE 90MPH.

Around town 17MPH is better than I usually get.

It may be of note that the '78 engine gets up on the "step", torque surge, only above ~4,000RPM.

So driving conservatively around town doesn't really buy you any FE.

Our '88 has a little "upshift" light and if I am "easy" with/on the throttle, and upshift by it religiously I can get 16-17 city.

But that's no fun, no fun at all.

Houpty GT

Remember the 78-79 cars do not have the O2 sensor or the compression (higher compression ratios increase efficency) that the 80-83 cars have.
I think the early SC's are suppose to get 21-23 mpg on the interstate and the later SC's are suppose to get 28-29 mpg. I do not think 17 is to far off for mixed driving on the early cars. You may want to have your CO% checked because that is what controls your fuel mixture. I have gotten 25 mpg out of my car for interstate driving but I am having issues with my computer which I currently have disconnected and have gotten 20 and 21 mpg on the last tanks with a little bit of mixed driving.

Also I see stickers indicating that the fuel pumps here all have up to 10% ethanol. I do not know anywhere I can get ethanol free. The blend is going to cost you about 2% on your gas mileage and change your fuel mixture. Max power is 15% rich and max efficiency is 5% lean so the 2% leaner mixture might be knocking you somewhere you were not before.

hebrewhomeboy

I do end up sitting at traffic lights for extended periods of time (yay hawaii traffic), so that's probably killing my mileage. So seems like this is pretty normal for a 78. Shame, I like the 78-79SC best since they're the lightest. Oh well, my next one might have to be an 80-83. Thanks for the help, guys.

Norske

My 85 Carrera got 28 on a trip from Denver to Raleigh. Drove most of the way between 75 & 80 MPH. I think the later cars got better mileage. my current beast gets about 16 around town and about 25 on the highway.

bourgeois911

I drive the livin pi** out of my 79 SC and I get around 19mpg at worst. On the road at a steady 80 or so I get between 23-24.

DARISC

I get 16-18 mpg around town. Once I got 24 mpg at 85-90 mph with the windows closed.

WHAT?! 4000 RPM?! The fun just BEGINS at 4000 rpm!

Just one 911 owner's opinion here, but these cars were designed and built, not just to drive, to be "DRIVEN", which is to say driven in a manner that causes driver exhilaration over the awesome capabilities these cars can exhibit when their potential is exploited skillfully.

The furthest thing I'm inclined to do when I drop into my 911's seat is to go out and drive it "very gently".

This is not to say that I ever drive my 911 "roughly"! The key word here, I believe, is "smoothly", which is how ALL machinery, not just 911s, should be operated.

That said, a 911 can be driven "gently", and to truely drive it gently it MUST be driven smoothly, or it can be driven agressively, which CAN be done roughly, which, not to put it gently, is stupid. Driven agressively and smoothly, the 911 is in its element and shines.

I believe the 911 was designed to be driven "spiritedly" ("agressively" can have a negative connotation, i.e., percieved as symptomatic of road rage).

There's a world of difference between taking one's 911 for "a gentle drive over miles of winding country roads" and taking one's 911 for "a spirited drive over miles of winding roads".
The former can be done with any car. The latter is where the 911 excels - and, if done smoothly, is not the least bit detrimental to the car; again, the 911 was designed to be driven that way.

My 82 SC RoW coupe is about to turn 200,000 miles without a rebuild, burns no oil betweem 5000 mi oil changes and I take it to red-line in one gear or another every time I drive it, which is nearly daily.

Gently? Under 4000 rpm? HA!