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Old 05-18-2003, 02:55 AM   #1
krazy_texan
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heres one for you guys with inline 6s

i am wanting to know what kind of gas milage are you getting, i have to go to college soon and need to get something that gets better gas milage than my 350 but i want a classic prefferably another truck like the one i have.
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Old 05-18-2003, 03:11 AM   #2
casey
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hey crazy texan how about a propane conversion, those kits a cheap used, or like I said car pool
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Old 05-18-2003, 05:04 AM   #3
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My 350 Burb is now getting 16-17 mpg. You can get a fuel efficient V-8. With propane you will actually get about 10-20 Percent worse mileage, but it usually is cheaper depending on where you buy it. Now I have heard that if you "fumigate" your gas with propane you can increase a couple of mpg. Im not sure if this is true though.
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Old 05-18-2003, 08:07 AM   #4
XXL
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Re: heres one for you guys with inline 6s

Quote:
Originally posted by krazy_texan
i am wanting to know what kind of gas milage are you getting, i have to go to college soon and need to get something that gets better gas milage than my 350 but i want a classic prefferably another truck like the one i have.
I can't tell you what mileage I get with my 6... I just put gas in it and drive, and my speedo's not right after the rearend gear swap. But... I'd say that you can probably get your 350 to be as efficient (or more) as the 6 is quite easily. The 6 is way underpowered for the weight of these trucks, so if you do any highway driving you're probably eating up a lot of fuel just trying to keep the thing rolling... whereas the 350 has enough torque to get the job done easily.

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Old 05-18-2003, 09:15 AM   #5
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my 76 with the 250 I 6 gets crappy gas mileage used like almost half a tank to drive maybe sixty five miles and thats with a three speed and only one burnout LOL
my motor needs a tune up badly though aint had a chance to work on mine yet.. you know how it goes the shoemakers kid is always the one running around barefoot
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Old 05-18-2003, 11:51 AM   #6
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My dad used to have a late 70's C10 with the 250, he said that it got crappy gas mileage, even worse than some of the V8 cars hes had. Those inlines have a really low comp ratio, which may be why. Probably if you built one to run higher comp and a few other doodads, you could get better mileage.
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Old 05-18-2003, 12:08 PM   #7
lukecp
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A friend of mine used to have a '71 GMC 1/2 ton with a 250, 3spd on the column, and 3.73 gears, and the best they ever got out of it was 11mpg. The engine had like 260,000 miles on it though. You could proably get you 350 to get a little better mileage. Since you have a 3/4 ton, you proably have 4.10 or lower gears. If you could find a way to put some 3.54-3.07 gears in it, that would give you better mileage on the highway. Also, you said you have a comp cam, how big is it? Anything over a Comp 268 will proably kill your mileage. Jet your carb a bit leaner too, and give the truck a nice tuneup, and you will proably get better mileage than an I6.

BTW, i am in the same boat as you. I am going to college this fall, and i need something that gets better gas mileage than my '72. I was looking on the internet.....and early ninties geo metros are about 1000 bucks, and get 45mpg. I dunno if i could drive one though, they are too small and underpowered, but if push comes to shove i may get one. Then if i don't have to drive my truck every day, i could go wild on the motor (bigger cam, lower gears), but i know i would miss driving it everywhere.
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Old 05-18-2003, 12:37 PM   #8
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Quote:
Originally posted by yellow72custom
BTW, i am in the same boat as you. I am going to college this fall, and i need something that gets better gas mileage than my '72. I was looking on the internet.....and early ninties geo metros are about 1000 bucks, and get 45mpg. I dunno if i could drive one though, they are too small and underpowered, but if push comes to shove i may get one. Then if i don't have to drive my truck every day, i could go wild on the motor (bigger cam, lower gears), but i know i would miss driving it everywhere.
Oh man, do I hear ya. This past year at college, I had to drive the Festiva back and forth...it's basically like a Geo Metro, but a Kia/Ford edition. I only drove my truck to school a few times but it wasn't worth it. I'd get about 45-50 mpg in the Festiva and you can't beat that with a stick. You just have to get used to people making fun of you all the time, and tell them, "If I ever see you again I will run your car over in my truck."
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Old 05-18-2003, 01:35 PM   #9
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There are a lot of variables here. My 74 C-10 bare bones 250/ 3 speed got about 16 after I took off the smog crap and put in a module for pointless ignition. My 80 G-10, with 250/ 3 speed had the integral intake with a two stage two barrel got about 19. Now my 52 with a 235, 4 speed and 4.57 gears only gets around 11. If you want economy, you need a smaller vehicle. At one time I had a Nissan ext-cab with 3.0 L V-6 and 5 speed, it got 22-28 mpg, depending on conditions.
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Old 05-18-2003, 01:47 PM   #10
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Quote:
Originally posted by yellow72custom
...and early ninties geo metros are about 1000 bucks, and get 45mpg. I dunno if i could drive one though, they are too small and underpowered, but if push comes to shove i may get one.
A couple of must-have options for one of these are 1) DARK tinted windows, and 2) sunglasses. That way nobody will see you when your driving it, or when you're getting in and out

Years ago I had a 3 month crunch between building a hotrod and waiting for my new ordered vehicle to arrive. I went to the local Ugly Duckling rental place to rent a cheapo from them but found it it would be cheaper to just buy something. So I became the "proud" owner of a bright blue Pinto hatchback. It was absolutely superb. It was in excellent condition, ran just fine, and it was so absurd for the people who knew me to see my driving it, we all just got a great big kick out of it. And... when my new truck came in, I sold the Pinto to my neighbor for a 50% profit! W00t!
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Old 05-18-2003, 03:36 PM   #11
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You can't really beat a mild 350 with overdrive for mileage in one of these trucks. My 350 with Vortec heads, a 700R4, and 3.73's gets 14mpg, and that's with me cruising fast and 28" tires. If you got a nice mild 350, with either a 700R4 or a 5-speed, and a rear in the 3.42 / 3.73 range, you could probably do that pretty easily as well.
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Old 05-18-2003, 05:30 PM   #12
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The sunglasses don't help. I have a 95 metro 4door that I drive to work everyday, and it is hard. I only bought it because I was sick of paying for the gas in my Durango and it was really cheap(600). I have heard quite a lot of ridicule from the guys I work with for driving it, but $10 a week compared to $40 keeps me smiling.
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Old 05-18-2003, 05:55 PM   #13
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I've got a 250 I6 in my 72'4x4 with the 4spd and 3:73 gears. Fuel economy sucks. I'm getting around 9-10mpg with the 1 barrel carb. My 71 2wd with it's 307 V8, 3spd tranny, and 4:11 gearing gets around 13mpg with a 2 barrel carb. The 250 I6 for me is just way too under powered for the 72' truck.
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Old 05-18-2003, 11:50 PM   #14
krazy_texan
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i found something that will be fun to drive and i go to test drive it tomarrow, i found a 75 dj5 postal jeep, cant wait to test drive it
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