Hi My Electra has between 11 and 13 miles pr gallon on the highway. If it had been a high performance engine, it would have been OK with that fuel consume, but not with a standard engine. The 73 Pontiac Grandville with a 455 . that I had earlier had between 13 and 18 miles pr gallon. Is there anybody who knows what numbers Buick had for these cars when they were new? How much fuel uses the board members Electras?
Honestly, that sounds about right to me. Remember that is a very heavy car with poor aerodynamics, a huge, inefficient smog-era engine with a choked off exhaust system and a 3-speed transmission without overdrive. You just can't expect too much in the way of fuel economy.
That's about right, unfortunately! My 1975 Electra Limited (same drivetrain, 2.73 posi rear) gets 12 at best, even on the highway. I attribute this to the low-compression, smog-era engine and current need of a carb rebuild. And 5200 pounds! Of course, if when it has aluminum high-compression heads, dual exhausts, a gear vendor unit......who knows?
Hi And thanks for the answers. The only thing I have changed is that I have double exhaust with Flowmasters. I had earlier a 78 Pontiac Catalina stw with a 69 428cid that I drove at 18 mpg on the highway. So I suppose I have to rebuild and modify the engine in the future. SBRMD Is your car original with Posi or have you installed it?
My boss's fully loaded '73 Electra got 27mpg on the way to Florida right after he bought it brand new. A few months later he topped that with 33mpg on the way to Washington State. He did have H.E.I and the rest was stock. Im hoping for 15mpg in my '73.
Rob, i think your boss is telling fish stories.Their is no-way a 73 Electra got anywhere near 33MPG. Tom
What gallons are we talking about.Imperial or American. In 71 Riv i get around 22 mpg cruising at 100 110 kph. I am talking Imperial Gallons. 1 Imp. equals 1.2 Amer. Tony. :beer Running a 750 vac sec holly.
We are talking US gallon, at least I am. As I told you earlier I had a 78 Pontiac Catalina stw with a 1969 428 cid and th400. This car was loaded with stuff, when I drove it home after I had bought it, there was an extra 425cid Olds engine,4wheels etc ,that was stored in the car and I measured the fuel consume between Oslo and Trondheim.(about 300 miles with OK Roads),and it had 18 mpg. So I am sure it is possible to get this mpg on the Buick too with highway driving. But maybe not without modifying/rebuilding the engine.
Something to remember is even highway driving is different. If you held it at 60mph for a long drive with very little slowing and acceleerating (IE optimum conditions) then I would say 11-13 is a little low. My Riviera is about 600 lbs lighter and gets about 16-18 mpg average on the highway. City is about 12-14. That's a 71 with a 76 motor 71 heads and performer intake.
I have no idea of what kind of mileage my car gets, but I think it has gotten better since I changed over to the HEI ignition system. It just feels like it's longer between refuels.
Gear Ratio Anyone? Hi Guys, An engine is basically an air pump that we feed fuel into and ignite it. Variations in fuel economy can be as simple as the rear end gear ratio. The lower numeric ratio (i.e. 2:56 to 1) will allow the engine to turn lower rpm which equates to the engine turning slower, using less fuel. This is one area that seems to be ignored when guys talk about fuel economy, lower the engine rpm at highway speeds equals increased fuel economy. This is another reason why you can't compare one vehicle to another for fuel economy without knowing the specifics on each car. High torgue engines like the Buick 455 can accelerate at a good rate (not Great!) even with these low numerical gears. The mileage of the 75-76 Buick sounds right in the ballpark. My brother had a 76 Estate wagon that knocked down about 12 on the road and 9 to 10 in town, nice car but very thirsty! :beer Tim McCluskey :Comp:
I wish I had a fourth gear on mine; sitting at 3200 rpm's at crusiing speed isn't exactly economical. That sure is a drawback with 3.42's, and it felt like the car had different sweetspots with the old 2.93's.
I got 20-21 mpg with my 69 LeSabre a couple of times back in the day driving back and forth to college. Probably averaged 18-20, and we always drove those trips pretty hard...lots of passing on 2 lane highways. That car had a 350 2 bbl, absolutely no creature comforts, the ST-300 trans, single exhaust, basically a stocker. That engine had 9:1 compression ratio and only around 40-50000 miles at the time. I'm sure it weighed significantly less than your Electra or most of the other cars being discussed here. Still, I was always quite pleased with those numbers for a full size Buick. I bet that 69 428 had higher compression ratio. THe 9:1 ratio in my LeSabres 350 was pretty low for the day. That would make a big difference. Lots more potential for economy/power with more squeeze per displacement. I'm still patting myself on the back for fixing teh gas leak on my Riv. It was leaking at least as much as it was burning for a while there, so my mileage is much better, although I have yet to calculate it, or even take it out of town yet. Actually, I'm quite sure it still sucks, just not quite as bad :grin:
You all are forgeting something, back in the muscle car era, how much was fuel? Less than a dollar per gallon? Back in the day, they didnt worry about mpg, they just got around because the fuel was not a top concern like it is today. Just my 2 cents! -Jake
Jake, what your forgetting is the fuel shortages started around 74-75 and were talking about gas mileage of a 73 buick. I don't know how old you are but i can remember quit well the fuel concerns of "back in the day". Tom
My electra gets roughly 12mpg in the city. The cruise control doesn't work right now, but I figure that I could probably do 15mpg on the freeway. A brand new 1976 Electra had an EPA fuel economy rating of 18mpg combined city and highway, not bad huh. It was 3mpg better than the 1975 combined average. I got that fact from the standard catalog of buick.
My 75 Limited also has a 2.73 posi and it does about the same 12 MPG on the highway. I never shut off the a/c or try to save gas by any means. My 76 Limited had a 2.56 open and the mileage was similar. My 65 Wildcat is more fuel efficient but it's lighter, it has a smaller 401 engine and it lacks a/c.
The usual suspects.... Weight, axle ratio, displacement, compression ration, engine/carburetor condition, etc.; the reasons for mileage are no mystery. I think the 1976 Electra came standard with a 350, while the 1975 was still standard with a 455, hence the difference in EPA ratings. A '76 with a 455 performs similarly to a '75, I would think. Engines and weight are the same. Jake: just curious - how old are you?
