How many mpg

[veinbar]

On my most recent road trip I achieved some very satisfactory mpgs. I drove from Austin, TX to Lubbock, TX @ 65mph averaging 16.9 mpg. On my return trip I faced a helacious headwind and averaged just under 14.5 mpg... I'm stoked. I can deal with those numbers any day of the week. This was my test voyage for my new carb and engine. Couldn't be happier with the outcome...

PS - I lied just now when I said I couldn't be happier. I could be much happier. So... I just didn't want to leave things on a lie like that. Are we cool now? Cool...

[Goldfinger]

305/700r4 all highway driving recent tune-up edelbrock 1406 tuned properly. I am seeing about 20-25mpg at 55mph with conservative driving. jack rabbit starts diminish this greatly.In the city I average 10-14mpg; my engine hates stop and go.

[Rightone1974]

Originally Posted by veinbar

My '79 SWB had a similar set up. Gas gauge not working in it either. If you know how many gallons your gas tank is, and your Odometer works, that's all you need. Example:

My truck had a 16 gallon tank, so I stopped at a gas station at or before 160 miles just to be safe(10mpg average). When you stop, write down the exact miles you traveled, and the exact gas amount that it took to fill your tank again. Divide the mileage by the gallons of gas, and you have your hwy MPG. Of course, my highway mileage was better than 10mpg but this is how I figured it out. If you're not getting 10mpg, turn around and go home. LOL

I used to get 15mpg with my edelbrock, but I switched to a SMI Q-Jet and now I get just under 18mpg. My engine is stock with the exception of open element air filter and dual 2.25" exhaust.

I disagree with you that that would figure your highway mileage, It would figure your average milage when figuring that way.

[veinbar]

Originally Posted by Rightone1974

I disagree with you that that would figure your highway mileage, It would figure your average milage when figuring that way.

Do you disagree with it because I didn't say "on a road trip you should..."? I was implying that if you're on a road trip with prodominately highway use, this is how to get your HWY mileage. Do the same in town to get your intown mileage.

there are phone apps out there that do all of this for you. Fuel tank capacity, distance traveled, fuel consumption, duration, avg speed, etc. That would be the most accurate way, but not everyone want to hassle with an app.

[Goldfinger]

just right down you milelage on a fullup then caculate distance gone to gallons used on the next fillup

[Rightone1974]

Originally Posted by veinbar

Do you disagree with it because I didn't say "on a road trip you should..."? I was implying that if you're on a road trip with prodominately highway use, this is how to get your HWY mileage. Do the same in town to get your intown mileage.

there are phone apps out there that do all of this for you. Fuel tank capacity, distance traveled, fuel consumption, duration, avg speed, etc. That would be the most accurate way, but not everyone want to hassle with an app.

Oh ok I got you. sorry

[79Silv4x4]

Originally Posted by Goldfinger

305/700r4 all highway driving recent tune-up edelbrock 1406 tuned properly. I am seeing about 20-25mpg at 55mph with conservative driving. jack rabbit starts diminish this greatly.In the city I average 10-14mpg; my engine hates stop and go.

25 mpg? GM should hire you as a consultant!

[veinbar]

Originally Posted by Goldfinger

305/700r4 all highway driving recent tune-up edelbrock 1406 tuned properly. I am seeing about 20-25mpg at 55mph with conservative driving. jack rabbit starts diminish this greatly.In the city I average 10-14mpg; my engine hates stop and go.

20-25 mpg? Did you mean to say kilometers per gallon? JK. What's even more unbelievable is that you're able to maintain 55mph on the highway without feeling anxious. I go 65mph on the highway, and I get passed by everyone like I'm standing still. At times I feel peer pressured into driving faster and watching my mpgs suffer.

[C-10 simplex]

Originally Posted by Rightone1974

I have a 68 gmc C20 with a 351m big block v6. What kind of mileage should it get on the average. The truck is bone stock.

i would be interested in knowing as well. Does your odometer work?

[VWBeamer]

1979 LWB 350/350 3.08
4 bbl 600 elderbrock

I get 12-13 mixed driving.

My 2004 Vw Tdi gets 42 mixed driving, sadly it's on Jack stands because I'm putting a clutch in it and it's big shock to the wallet have to drive the truck every day.

[piecesparts]

Originally Posted by Goldfinger

305/700r4 all highway driving recent tune-up edelbrock 1406 tuned properly. I am seeing about 20-25mpg at 55mph with conservative driving. jack rabbit starts diminish this greatly.In the city I average 10-14mpg; my engine hates stop and go.

I quess I am impatient. I would much rather pay for the gas and drive at a speed that I like, than let every semie and beetle bug pass me and get better mileage. I get 15 MPG with a 400 HP stroker 383 engine, 700R 4 tranny and 3.73 gears. I know the cost of HP is not cheap.

[VWBeamer]

Yea. I hate being passed. On the highway I drive a little faster than most.

[Goldfinger]

i'm running 2.73 gears in my rear and i run with my tires a little over inflated. my rpms stay low. If you want to get the best mileage possible get a vacuum gauge and you'll learn how to drive right.

[rare86]

This is a question that truely has to many fators to give an accurate answer. Highway speeds, flat ground or multiple hills and inclines, stock size tires or bigger/smaller, hi daily temps or cool days. My extended crewcab gets about 11 average. My 86 excab 2wd, 305/700r4 with 2;73s and one inch larger than stock tires in the rear gets. 18-19. My big red 4wd gets 12-13mpg with 350/th350/3.48s and 35 inch tires. I also live in west texas, its flat, hot but very windy. I can garauntee the wind here will mess up your mileage.
How well your truck is tuned up also plays a huge factor. If you only get 10-12mpg out of a half ton 2wd truck with stock tires, you have issues or a lot of hills to climb.
Describe the terrain youll be driving, flat or mountainous, and what speed averge. Then you can get an idea based off of somneone here who drives in the same conditions.
If all else, Id start by filling up after the first 150 miles to get a base line and then figure average mpg x size of tank and get a baseline on how far a tank will go. I would only go about 75 percent of that for safety.