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-   -   yet another MPG thread (https://67-72chevytrucks.com/vboard/showthread.php?t=410665)

68longhorn 07-06-2010 12:07 PM

Re: yet another MPG thread
 
86 swb, 305/700r4 2.73 rear, P275/60R15 all the way around and I get 17mpg mix of city/highway. I've gotten as high as 18.7mpg and as low as 8mpg, but 17.xx is average.

Chlsnk 07-06-2010 12:26 PM

Re: yet another MPG thread
 
Im guessing about 12mpg on a good day with my 355.

iroc12valve 07-06-2010 12:34 PM

Re: yet another MPG thread
 
I get about 11 MPG average. 13 if im towing, Strange eh ? thats a 2005 4.6 ford F150
my old 86 C10 350/350/4.11 gears got 19
my 89 camaro 305 got 27mpg all day long but failed an e-test
interesting huh

Jonboy 07-06-2010 02:06 PM

Re: yet another MPG thread
 
Mine is getting close to 18 when I do drive it to work. the SEFI and overdrive do wonders. It has pretty decent power, too.

Trick76 07-06-2010 06:53 PM

Re: yet another MPG thread
 
1984 longbed 6.2l/700r4 23mpg hwy

Irish's_79_Step 07-06-2010 06:59 PM

Re: yet another MPG thread
 
either zero or infinite. she doesnt run, turn over, cough, nothing.

Big Port Jimmy 6 07-06-2010 08:43 PM

Re: yet another MPG thread
 
454 tbi 400 3.08 gears 6mpg in town 11-12 highway.

The 308s make it lug itself right out of the power band in town. thats why a 5.3/4l60e and some 3.42s are laying in the shop floor. Mines a DD, and I care about mpg. Jay

staggerd86c-10 07-06-2010 09:16 PM

Re: yet another MPG thread
 
well my mileage isnt good at all. I dont sell crack but I wouldnt stop driving my truck if it only got .5 mpg, then again I only drive my truck for fun. I think calculating mpg on these trucks can never give you a consistent result. if your going against the wind you can cut the mileage in half.

irishman999 07-06-2010 09:42 PM

Re: yet another MPG thread
 
I read the Quadrajet carb is more efficient than a 2 barrel. I got a 305, 4 speed 4x4 and the quadrajet, what could i expect as mileage?

DubDubU 07-06-2010 09:48 PM

Re: yet another MPG thread
 
I get a 1000 smiles a gallon

tucsonjwt 07-06-2010 10:31 PM

Re: yet another MPG thread
 
83 C20 stock Mr. Goodwrench 454 (slightly bored over) rebuild with 4 spd granny and 4:10 and gear vendor: 11 city, 13+ highway (but can go down to 9 city when using it as a dump truck or idling a lot.)

spinem 07-07-2010 05:12 PM

Re: yet another MPG thread
 
Quote:

Originally Posted by irishman999 (Post 4076725)
I read the Quadrajet carb is more efficient than a 2 barrel. I got a 305, 4 speed 4x4 and the quadrajet, what could i expect as mileage?

The motor wants fuel, with a 2 barrel you have to put your foot in it to go anywhere, the 4 barrel is allowed to "sip" on fuel and douche it when needed.

Giving your 305 is tuned alll the way areoung, id guess 14mpg give or take

KEEP EM COMMING!!

chevymotocross 07-07-2010 05:49 PM

Re: yet another MPG thread
 
87 2wd swb, 305 TBI/700r4, 3.08 gears. 14 Mix. I would like to bring that up a tad. I drive it pretty easy. The transmission needs a rebuild, it slips a bit between gears so that probably doesn't help. The 305 is in good tune but definitely has some miles racked up. My s10 blazer 4x4 with the 4.3 tbi gets 17 mix, but is way underpowered compared to the 305 in my truck.

Future plans: rebuild 700r4, swap in an L31 350 Vortec while still using the TBI injection.

85burb 07-07-2010 07:49 PM

Re: yet another MPG thread
 
7-8 mpg. 350/700r4/4:10 gears/ NP208/85 burb. Thats in town mixed punching on it and fuel sipping. 6.0L sitting on stand waiting for rest of parts. Will be carbed but hope to get same mpg with WAY more power. That will deff make the smiles per gallon go up.:lol:

78 Chevyrado 07-14-2010 10:10 PM

Re: yet another MPG thread
 
http://i160.photobucket.com/albums/t...-i-t/8-mpg.jpg

hitcher 07-15-2010 12:56 AM

Re: yet another MPG thread
 
just bought an 88 1 ton crew cab 4x4 with a 6.2 diesel auto no overdrive . any idea what kinda mpg im gonna get once its on the road ?

qu1cks1lver56 07-15-2010 02:55 AM

Re: yet another MPG thread
 
350 built a little with long tubes, TH350, 3.42's out back on 235/75's 10-13mpg

68 TT 07-15-2010 08:55 AM

Re: yet another MPG thread
 
340 hp 350, 5.13 gears, SM465, 32" tires, 5200 pound 3/4-ton 4x4 = 7 mpg city, 9 mpg highway.

Nothing like 4000 rpm on the freeway to suck down the fuel.

big10ratrod77 07-15-2010 09:43 AM

Re: yet another MPG thread
 
Quote:

Originally Posted by DubDubU (Post 4076736)
I get a 1000 smiles a gallon

amen... i love to drive my truck and at one time it got good milage! when it was stock!!! for real when my 77 big ten was just single exhaust and all that i had no urge to kick in the 4bbl and i could go a month on 40 bucks of gas. i bet if i kept it at 55 back then i was geting 14 or so to the gallon. but when skool started back i wanted a good sounding truck. so i asked mom if i could get duel exhaust for my truck to "help my milage" (dont we all tell this to our parents just to get more power?) well i dumped like $350 between duel exhaust through summit turbo mufflers, k&n air filter, and a flex fan. it probly helped a little but not much, it did more hurt than help i think couse every where i go now i make them pipes do some talking and i probly get like 8 or less becouse of jack rabbit starts and all that. but if i changed my driving habits id be getting "good milage"... for these trucks

but if my 350 ever blows i want to drop in a 250 stright six and a t5 and make it a nice high way cruzer

glock35ipsc 07-15-2010 10:25 AM

Re: yet another MPG thread
 
18-19 in town, 20-21 on the highway. 5.3, 4L60E, 3.42.

Once I have a new truck bought, then the 5.3 will get built up, or replaced with a 6.0 and built up. By then, I won't get two poops what it gets for mileage.

glock35ipsc 07-15-2010 10:26 AM

Re: yet another MPG thread
 
Quote:

Originally Posted by spinem (Post 4075460)
......well it should be. You can determine many issues by mpg, stoich, brake drag, vacc leak, hei spring advance exc.....

so before you go on here bragging, think about efficiency, because I DON'T GIVE A DAMN IF YOU DRIVE A PRIUS. but for those who dont sell crack, mpg matters.

keep your a## whole comments to yourself

This crap needs to stop, NOW, or you just might get a free vacation.

Keith Seymore 07-15-2010 10:28 AM

Re: yet another MPG thread
 
4.3L V6, MY6 OD trans, 3.73 rear axle, P235/75R15 tires = around 20 mpg.

K

powerdriver 1958 07-15-2010 06:55 PM

Re: yet another MPG thread
 
Umm , I have a one ton....All you need to know is,It has 2 20 gallon tanks........Nuff said.

Sillyoldman 07-15-2010 09:39 PM

Re: yet another MPG thread
 
I get 8 mpg's out of my 402. It costs me $18.00 each time I drive it to work & back. Just did it today for the second time this month. In no way could I afford to do it all of the time. I sure enjoy it when I can. It's worth every penny.

Hubscrub 07-15-2010 10:51 PM

Re: yet another MPG thread
 
last i checked was around 10ish, 85 4x4 lwb 355, aftermarket cast heads, mild cam, 700r4, 4inch lift and 33's


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