Re: What kind of gas mileage do you get with your 67-72?
 

my 67 C10 - 283/powerglide and 3:73 rear. I don't know what it gets but it isn't good! I haven't run the numbers but my guess would be around 10. The gas gauge moves pretty quick.

Re: What kind of gas mileage do you get with your 67-72?
 

‘67 GMC 250 L6, 3 on the tree, SM 3.54 rear end, 15 mpg on the highway.

Re: What kind of gas mileage do you get with your 67-72?
 

Snotty 355 with a TH350 and 3,000 stall. 3.73 butt gears with limited slip.

6 with my foot in it, 8 with it out.

Gas mileage is for Honda's... :lol:

Gary

Re: What kind of gas mileage do you get with your 67-72?
 

Nearly same setup as OP and get 12.5 with non ethonal. Never checked with ethonal blend because it doesn't start as good and rarely use it. Non highway driving with start/stops.
I need to take it for an interstate drive and see.

Re: What kind of gas mileage do you get with your 67-72?
 

Mine is the original 350 V8 with a 4 barrel qudraflood carb and a 350 at trans . Never been into the engine and has 113,000 on the odometer. I drive it like a old lady going to church. at 5200 feet elevation I have seen 11mpg and up to 15mpg The old engine could use a freshen up. The carb was rebuilt and restored to factory specs. I am still running a distributor with points. :metal:

I forgot that this is a 2 wheel drive short bed truck .
Vic

Re: What kind of gas mileage do you get with your 67-72?
 

Before the rebuild, I believe it was in the neighborhood of 11 MPG for my stock 402/400TH. The engine was rebuilt in 1993, punched out and high performance heads off a 60s Corvette/Camaro. I've never checked and haven't cared to, but 8-9 is probably right.

Re: What kind of gas mileage do you get with your 67-72?
 

I feel like I'm at a gas station every 20 minutes...
Big Block Problems!

Re: What kind of gas mileage do you get with your 67-72?
 

I haven't bothered to check my fuel mileage in many, many years -- it is what it is, and it ain't anything to brag on! Many years ago I made a round trip from NorCal to eastern Kansas & back, about 3000 miles or more iirc. This was when the 55 mph law was in effect, and my truck isn't real happy going much faster anyway. I got between 10.5 - 11 mpg on that trip. '72 K20, stock 350 with TH350 trans and 4.10 gears. At that time I was running 7.50-16 bias-ply traction tires on split rims.

Re: What kind of gas mileage do you get with your 67-72?
 

69 shortbox fleetside with a 400sb and a TH350 and a 3.73 posi. Best I ever got was 13 but I only ever saw that once as I recall. Typically 10 or between 8 and 10 when towing one of the cars on an open trailer. The truck originally had 3.07 gears and I had the 400 in there for a short while with those gears, but the mileage didn't really seem to change when I upgraded to the 3.73s. I still have those 3.07 gears lying around if anyone could use them....

The original 307 engine didn't really get better mileage than the 400 I have now, but it was pretty tired when I got the truck. The 400 was pretty much a win-win when it went in.

Re: What kind of gas mileage do you get with your 67-72?
 

THIS!!!:lol:

Re: What kind of gas mileage do you get with your 67-72?
 

Gas mileage! We don't worry about stinking gas mileage!........:ito:

I have a 350/400 with 3:73 rear getting around 8 to 12 mpg depending on how much my foot is in it.:burnout:

Re: What kind of gas mileage do you get with your 67-72?
 

250 Straight Six one barrel with a powerglide and 3.73, got 10 mpg
250 Straight Six four barrel with a powerglide and 3.73, got 9.75 mpg
454 Big Block with two fours and a 4L80E and 3.73 rear, get 9.75 mpg which seems like a bargain!

Re: What kind of gas mileage do you get with your 67-72?
 

250 Straight Six one barrel with a powerglide and 3.73, got 10 mpg
250 Straight Six four barrel with a powerglide and 3.73, got 9.75 mpg
454 Big Block with two fours and a 4L80E and 3.73 rear, get 9.75 mpg which seems like a bargain!

Re: What kind of gas mileage do you get with your 67-72?
 

I've had 4 trucks, all v8, and gotten between 11 and 13 combined. Best ever from my bone stock 307/3ott/3.73 truck, 16mpg, all 60mph back roads.

Re: What kind of gas mileage do you get with your 67-72?
 

When mine was running it had the original 327 in it. I'm working on putting a 350 into it now, but with the 327 I was getting about 12-13 MPG. I could squeeze it up to 14 if I was really careful with the gas, but what's the fun in that?

Re: What kind of gas mileage do you get with your 67-72?
 

68 swb, 292 with electronic ign and holly 4 bbl, A833 OD, 3.73 rear....16.5-17.5 mpg.

Re: What kind of gas mileage do you get with your 67-72?
 

9 MPG. 69 K20, 350, 4 spd, 4.56 gears, 33inch tires. All stock, all original.

Re: What kind of gas mileage do you get with your 67-72?
 

I have a 406 with a TH400 transmission and 3:07 gears.

I don't really know what the mileage is. I never worried about it.

I just know that I can't leave the engine running while I'm filling the tank, or I can never get it full.

Re: What kind of gas mileage do you get with your 67-72?
 

'72 307 2-Barrel, 3-Speed Manual, 3.73 Rear, an all around 12 to 15 as an approximate. I never did check it mathematically. One reason why is I know that my Speedometer/Odometer is off some. Mainly due to my tall 265/75/15's on the Rear.

Re: What kind of gas mileage do you get with your 67-72?
 

Yep. I've always heard it doesn't much matter what stock engine is under the hood, there's going to be little difference in MPG. Less 4WD applications, I believe the real difference is longevity. The smaller the block the longer span between rebuilds.

But tough to see past the look and feel of a BBC.

Re: What kind of gas mileage do you get with your 67-72?
 

That's actually pretty good for a 4x4 with those gears! :metal:

I checked mine today and it actually got into the 11s :chevy:

Re: What kind of gas mileage do you get with your 67-72?
 

I get 7 miles to he gallon, 4:11 gears,4200 converter,team G intake, thinking thats not bad, stock was 16 miles to the gal.

Re: What kind of gas mileage do you get with your 67-72?
 

Where is the guy beating the dead horse emogi when you need it? Lol!!

Im really just joking. I love the milage threads. Im a mpg geek with my BBC 'Burb. Its kinda out of necessity as I have never bothered to fix the fuel guage.
I typically average 8 mpg in town. Lots of stop and go and short drives. On the highway, keeping below 65 mph., I can average 13.5-14 mpg. This has been checked 3 times this last year driving the same two lane highway over the Cascade Mountains. I used to average 12.5 on this trip with the old AFB, but recently swapped carbs to a 600 Edelbrock and I picked up 1 mpg highway.

This is a stock smog era 454 with peanut port heads, Eddy rpm intake with a 1" phenolic 4 hole spacer, 38 degrees total initial and mech. timing, and clutch fan. Trans is a TH400 with shift kit, 3.07 gears, and 29.5" tires. Its a 2wd that has approx a 4" drop.

I used to own a '69 C10 lwb with a rebuilt 250" 6, 3 OTT, and 3.73's. The best highway mileage I EVER got was 16.5. This was on a flat freeway drafting behind a semi.

Re: What kind of gas mileage do you get with your 67-72?
 

How are the rpms going down the interstate?

Re: What kind of gas mileage do you get with your 67-72?
 

8 mpg but will get 11 on the highway. 72 K10 Engine: 350, Trans: TH350, Gears: 3:07, Tires: 31.5 10.5 15