Yes we average from fill up to fill up when we are keeping an eye on mileage. However we only do that when we are taking longer trips, day to day driving around, she usually just puts in 20 or 40 dollars at a time. (we are in Canada where gas is nearly $6 per gallon for cheap stuff and 6.40 a gallon US$ for Premium, so fill ups can be close to $100 bucks if using higher grade gas. I also use the Instant and Average fuel calculations from the OBD2 Port. I keep a Bluetooth OBD2 Scanner plugged in all the time in the truck, so anytime I want to see what's going on, I just grab my phone and load up the software to see what's going on. (Yes I am that Anal about keeping on eye on engine data) Oh someone asked about Ethanol, if we run normal gas, 87-91 its 10% ethanol, however Chevrons here in Canada sell 94oct that is Ethanol Free. We occasionally use it, as I think the Techron is better at cleaning out the engine and we get zero detonation when running it. I am always disappointed when we are state side that we can not get the 94 ethanol free stuff down there. At one time only certain stations had ethanol gas, so we would always avoid them, but over the last year, all stations started using up to 10% in their low grade fuel. I finally gave in and tuned the Fiero for it, but I still hate it.
The trip or odo (if proven masuring accurate against a GPS) is the only good way to get the mileage IMO. I have a friend who says "my car gets 40 mpg" Because the live readout on his dash says that when he is cruising. I dont consider that accurate. Gallons used divided by miles driven is the only way. 94 octane thats gonna get you some gooood mileage too. It costs more here just to get any gas without ethanol in it, my mileage is 87 octane E10.
The trip or odo (if proven masuring accurate against a GPS) is the only good way to get the mileage IMO. I have a friend who says "my car gets 40 mpg" Because the live readout on his dash says that when he is cruising. I dont consider that accurate. Gallons used divided by miles driven is the only way. 94 octane thats gonna get you some gooood mileage too. It costs more here just to get any gas without ethanol in it, my mileage is 87 octane E10.
Running 87/E10 gets is our worst mileage, and there is audible detonation, so we simply don't run it, we try to stick with 89 as a minimum. I really hope those trip meters are wrong, as we got our GTP back from the shop with a new trans last weekend and driving it around last week and this weekend the average meter is showing 13.5mpg OUCH, LOL. We have not driven it enough to run a full tank through it to check with the odometer.
As for our Blazer I use the odometer as the primary and the ecm output as an aid. You are right, dead nuts distance traveled vs gallons used is the only really correct number.
------------------ 857GT Part 85GT Part 87GT Part Caddy, 93 Eldorado 4.9, 5spd Dual O2 Custom Chip, Custom Exhaust. MSD Everything Now with Nitrous. Capt Fiero --- My Over View Cadero Pics For Sale $4000, Yellow 88GT 5spd Full Poly Suspension, Lowered 1/2" in front, Corner Carver.
Your 4.3 AWD gets 32mpg and audibly detonates with 87 octane? Ha, ya, right..
I can see you are trying to pick a fight by stretching out what I said, I said between 28 and 32 on the highway. As in Pure Highway, it has gotten a high of 32, could have been an elevation change going from one area, to another over a 300+ mile area, maybe we had a good tail wind for a hundred miles. I also said in a later post that in city driving its closer to 20mpg. So no I never said its gets 32mpg all the time. I also stated that it became detonation sensitive after the addition of the E3 plugs and distributor change, along with the replacement of the entire top end including spider injection assembly. I am actually surprised and happy at how it drives and the gas mileage it gets. Its a factory odd ball, and every once in a while GM assembly line workers spit out something that sets the high side of the average for all vehicles produced for that model line. Its also possible that in the nearly 20 years since it was made, someone popped a head gasket and it had the heads decked. Who the heck knows and who the heck are you to claim to know what is going on.
------------------ 857GT Part 85GT Part 87GT Part Caddy, 93 Eldorado 4.9, 5spd Dual O2 Custom Chip, Custom Exhaust. MSD Everything Now with Nitrous. Capt Fiero --- My Over View Cadero Pics For Sale $4000, Yellow 88GT 5spd Full Poly Suspension, Lowered 1/2" in front, Corner Carver.
the AWD 4.3 is by far the biggest gas guzzler , yours must have some special engine work done to get that.
my featherweight basic s10 (141k) gets exactly 17mpg in the city with the AC on, have not tried AC off nor highway (live in the hot tropics), and thats average driving, not babying it all the time, but never ever dogging the thing. Thats why it still feels new at 141k , its never been dogged.
[This message has been edited by DanDamage (edited 04-01-2014).]
Remember kids. Change your spark plugs and you're Blazer will beat GTP's, get 50% more gas mileage, and will detonate on 87.
In other words, you're full of $hit.
Nope Wrong Again, I said it would beat it through an intersection and a bit more, then the GTP gets Traction and Boost and walks on by. From a dead stop, the front wheel drive GTP either spins or the traction control pulls it down to a slug. So I am not full of anything, but you are an idiot and a troll.
------------------ 857GT Part 85GT Part 87GT Part Caddy, 93 Eldorado 4.9, 5spd Dual O2 Custom Chip, Custom Exhaust. MSD Everything Now with Nitrous. Capt Fiero --- My Over View Cadero Pics For Sale $4000, Yellow 88GT 5spd Full Poly Suspension, Lowered 1/2" in front, Corner Carver.
I guess I must be an idiot. My Fiero is significantly lighter than your blazer, has far better aerodynamics, better gearing for mileage, a more efficient engine, far more advanced fuel injection and ignition components, and a more efficient drivetrain. But yet I barely get the same fuel economy. Maybe I need new spark plugs. Ya, that's it.
And by the way, your statement on fuel economy being better with rpm is absolutely false. Lower rpm, within reason, will always yield better economy. That's why gearboxes today have 8, even 9 speeds. Better economy without hurting acceleration.
I guess I must be an idiot. My Fiero is significantly lighter than your blazer, has far better aerodynamics, better gearing for mileage, a more efficient engine, far more advanced fuel injection and ignition components, and a more efficient drivetrain. But yet I barely get the same fuel economy. Maybe I need new spark plugs. Ya, that's it.
And by the way, your statement on fuel economy being better with rpm is absolutely false. Lower rpm, within reason, will always yield better economy. That's why gearboxes today have 8, even 9 speeds. Better economy without hurting acceleration.
Just curious what drivetrain do you have in your Fiero. Most 2.8's with mods can attain 30mpg on the freeway, and newer 3.8's, 4.9's and other motors can get even better. 87 Duke 5spd being the best gas mileage if driven at normal speeds.
Ya know why they have 9 gears and not just 3 really tall gears, its to keep the engine in the optimal rpm range which is NOT idle speed or lugging the motor. If engines worked best at the lowest rpm range (within reason, like you said) we would all have 1 gear for take off and then 1 or 2 additional gears for cruise speeds, however that is not the case, keeping an engine at optimal speed for acceleration vs optimal rpm for cruise are 2 different things, if you LUG a motor down while trying to accelerate vs having it closer to a mid range rpm it will use more fuel. That is why we have 8 and 9 speed transmissions.
If a CVT did not have such horrible power loss through it, most cars today would be running one. Heck I think it would be cool, to be able to in theory set my engine rpm to 4800 and let the trans gradually adjust ratio as the car accelerated. Max acceleration while staying in the middle of the power band. Then once it reached a set speed gradually bring the engine rpms down as the cvt continued to adjust the ratio to maintain speed. However its like the Wankle cool concept...... but horrible in reality.
------------------ 857GT Part 85GT Part 87GT Part Caddy, 93 Eldorado 4.9, 5spd Dual O2 Custom Chip, Custom Exhaust. MSD Everything Now with Nitrous. Capt Fiero --- My Over View Cadero Pics For Sale $4000, Yellow 88GT 5spd Full Poly Suspension, Lowered 1/2" in front, Corner Carver.
What's there to understand. Lop 2 cylinders off a 350 Chevy and you get a 4.3. Same gas mileage, same pros/cons, less power/torque and more expensive.
Lop 4 cylinders off a 305 and you get the same displacement per cylinder as a Duke Fiero motor. Decent torque no horsepower, however wait, the duke is not too bad on gas mileage. (at least the 87 5spd)
why same gas milage? i know its like 170 hp right?
I don't know why the gas mileage on MOST 4.3s are so bad (for what they are). I know what I get and that's about the same as MOST other 4.3 owners. Some get much worse, some get much better. I DO know that I've driven full size trucks/SUVs with a V8 (4.7/5.0/5.2/5.7/etc) that have gotten the same or better gas mileage. If you can figure out the answer, you'll make a lot of friends in the 4.3 arena.
My Fiero has a 3.4 DOHC turbo through the factory Getrag. I average right at 30 on the highway, driving carefully to stay out of boost.
Cruising RPM is a huge consideration on fuel economy, with the best being just about as low as the motor can go. However there are other considerations. The vehicle needs to be able to maintain speed without excessive downshifting, and without going into power enrichment.
The 4.3 gets horrible economy for a lot of reasons. It's horribly inefficient in every way. The fuel injection was behind the times with every iteration, same with the ignition. The combustion chamber design was also very poor throughout it's lifespan. It's also naturally unbalanced. And because it makes sh!t for power, and is in front of a 4-speed auto, the highway RPM needs to be kept high for the above reasons. In the later years GM went to the LSX. Besides being the best automotive engine ever produced, it was leaps and bounds above the 4.3 in every way (SFI, coil on plug, good chamber design, good head design, etc). And because it made a lot more power, it could run at considerably lower rpm on the highway.
In the later years GM went to the LSX. Besides being the best automotive engine ever produced, it was leaps and bounds above the 4.3 in every way (SFI, coil on plug, good chamber design, good head design, etc). And because it made a lot more power, it could run at considerably lower rpm on the highway.
Got one laying around? I'll take it off yor hands.
[This message has been edited by 2.5 (edited 04-03-2014).]
3, actually. Which shows the engine's tremendous versatility. A 5.3 in a Silverado, a 5.7 in a SS Camaro, and a 6.0 in a big delivery truck. And as soon as the body is finished, I'll be building one for a 55 Chevy. Hopefully a twin turbo, but S/C might fit the car better.
I'll go along with RobertGT with regards to the 4.3 MPG. 30+ MPG in a 4.3 AWD Blazer in ANY situation I'd categorize under "internet car forum MPG claims."
I do own a 1987 Astro with a throttle body injected 4.3 A/T and 3.42 rear gears. 20 MPG is rare but achieveable under perfect conditions.
My son owned a 1996 S10 with a 4.3 A/T with 3.42 gears with the same MPG figures as my Astro.
My experience wth any year GM 4.3 (in a truck type vehicle) is it is VERY consistent in delivering crappy MPG.
I have a 4.3 in a stripped WT 2002 Silverado. Typivcally around town get about 19.5 mpg in the summer. If I baby the truck in the summer on the highway I have gotten in 23.5 to 24 mpg fairly normally---this is babying it on long highway trips.(65mph or less). Typically in the winter get 17mpg or 15mpg with with four snow tires. These are real numbers, I log every fill up with the odometer milage, the tripometer milage, hours and fuel consumed.
I do see the 4.3 being slightly more fuel efficent than it's V8 big brother. Is it significnatly more efficent? No. Maybe 10% better normally; 15% on a good day.
Overall the truck is generally a dog in terms of power but it runs and get the job done. it is a dog even in a light truck weging in at ~4400lbs. I accept the engine for what is it and don't expect oo much.
The "general" structure of the engine is as old as could be...from the early 1950's with the 265/283. While the 4.3 is a dinosaur it is rock solid and reliable, kind of like the Buick 3300/3800/3.8?
