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Fuel economy

I have a 88 chevy caprice…305cu in v8 automatic trans… This car has been getting 25 mpg with the carbeurated v8. Why is it so difficult for car makers to bring newer cars to higher standards…

Ok so it probably has a 2.55:1 rear axle and the automatic has overdrive. on the highway i am just about 12oorpm at 65mph.

My first car was a 68 caddy coupe deville…(yes I like big cars…) and i remember getting about 20mpg with that car with its 472cuin v8…(and a teenage driver to boot)

my fuel economy measurements have always been gallons to fill the tank divided into miles traveled. I learned to keep accurate records from my father who wanted me to keep track of everything… I almost always leave a full tank in my cars and drive a combination of highway and around town (50/50 mix)

Whats up in Detroit?

You have a slower car with less safety equipment, that helps economy. I imagine a new Accord 4cyl would be faster and get better economy, much better crash performance, better handling, with almost the same room.

"My first car was a 68 caddy coupe deville…(yes I like big cars…) and i remember getting about 20mpg with that car with its 472cuin v8…(and a teenage driver to boot) "

That NEVER happened…Those cars would empty a 24 gallon tank in 250 miles…

The caprice is a slug, and puts out far more in terms of emissions than a modern vehicle.

Take a look at a new Camaro. A V6 that puts out over 300 hp and gets 30mpg on the highway and nearly 20 in the city. Your caprice has a V8, that puts out about 160hp and gets about the same in terms of mileage. Which is more efficient?

And whats up in Detroit? You are obviously suffering from a severe case of perception gap. Japanese and European gasoline engines are not producing higher mpg ratings than “American” engines.

the accord is not an 8 passenger vehicle… I drive my fathers 98 accord 5 speed 4 cyl and i get 33mpg regularly, by the way I stopped driving the caprice recently because of an accident that crushed the fender. Hit by a drunk driver and is still driveable after a 35mph head on. and all 4 passengers (wearing seat belts) were unhurt. but that is a story for another day…lol

The caprice was not an 8 passenger vehicle either, not even close. Which is why it only had 5 seat belts, same as the Accord.

i was just looking for my old notebooks but I think my dad thru them away years ago. He made me write down all the mileage everytime I filled up and I regularly went nearly 340 miles per tank and never let it get to empty. the only mods on that car were disc brake conversion and dual exhaust. I did alot of road trips since I had room for many friends… but regularly refilled it every 10-12 gallons. Taht was about once a week driving to school and work which would be about 200 miles a week…

You need to sit in a 2009 Accord. Much larger than the 1998. And where did “8 passenger” come from?

kgcharacter has a vivid imagination it would seem.

You must have been one of the lucky few who got one of the cars with the experimental “Fish” carburetors…As everyone knows, the oil companies bought up the patents and destroyed the design…Too bad…

If it’s the stock LO3 305, then it has Throttle Body Fuel Injection, it’s not carbureted although the TBI setup looks much like a carb from the outside.

Credit for the good fuel mileage goes to low gearing as you mentioned, more lenient emissions standards and the fact that it doesn’t weigh as much as you may think for the size of car it is, it weighs about 3600 pounds, and the fact that the L03 is the low performance variant of the 305, it’s cammed for more low end torque than ultimate HP.

With the revised (re: more realistic) EPA estimates you should be getting 15 city, 22 highway. If you’re getting 25 MPG, then you are doing better than most.

Edit: It maybe possible to have the LG4 4bbl 305 in the 1988 Caprice, I’m reading conflicting reports on the subject.

How often have you measured the gas mileage of your Caprice, and how?? I had the exact same car for 11 years , and the very best highway I ever got was 22.5 mpg and the average was between 18 and 20. If you go back and check the EPA mileage figure, you’ll find that this 25 mpg would only be achieved with a good tail wind, and all acessories OFF.

People wax euphoric when talking gas mileage of a car they liked. On this forum, please be very realistic and ACCURATE when you boast about your mileage.

As for the rest, I agree with the others, 140HP in a 4000 lb car with automatic made it less than a hot rod.

Mine had a 4 barrel carb, and the final drive axle ratio in overdrive was 1.41.

It had 6 seat belts, but the middle passenger in the front needed to be a midget.

I usually got pretty good highway mileage with the various V-8 powered land-barges I’ve owned over the years, like usually in the low 20’s. But the around town mileage was always always abysmal. It is definitely all about the gearing.

And you can pretty easily cram 8 people into one of those old Caprices, especially if it has vinyl seats. That doesn’t mean it’s a good idea, though!

Ahh I did’t remember that one. I had an 82 Caprice. With the split bench and folding armrest I think the front center belt probably spent most of it’s life under the seat…

In a Caprice wagon for sure!

FoDaddy you know your stuff, my 93 Caprice with the L03 and a 2.56 rear was rated at 17/24 under the old system, so 15/22 sounds about right.

I’ve had the car for seven years and check the mpg every 3 tanks or so (~1000 miles). Before NJ went to E10 year round, the car was averaging 22-23 mpg in local (semi-rural) driving. With E10 the mpg dropped to 20.5 -21.5 mpg. I estimate the highway mpg is 25-26 mpg.

These mpg numbers were obtained on an old set of Dunlop D65s Touring tires that had very low rolling resistance (and traction). The tire were replaced in March and the mileage has dropped to ~20 mpg. Still not bad the size of the car though.

Ed B.

There are two things that many men boast about, one of them is their gas mileage, you can probably figure out the other one on your own.

“… but the middle passenger in the front needed to be a midget.”

Not so! But they did have to be on good terms with the other front passenger to share the foot well! :wink: