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Old Dec 2, 2010 | 08:40 PM
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Engine advice

Hello, I am new to this but I am looking for a little advice. I own a 1977 Ford F250 Ranger. I love this truck but I am running into issues with fuel economy. I was looking at replacing my 400 big block with a 302 engine. What I am having trouble with is finding the best one for the job. Hopefully everyone out there can help me out. One other issue that I am having is when I bought This truck it only had one gas tank and it originally had two. Now I can not read my fuel gauge like accurately. Without trying to find and rewire a second gas tank, what should I do? Thank you for your time, John
 
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Old Dec 2, 2010 | 09:51 PM
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These trucks were not designed for fuel economy. If your truck is a 4x4 F250 you may even lose some MPG going to a 302 (and a lot of power). The money you would spend for all the parts needed for an engine conversion could buy a lot of gas and pay for any difference in cost savings you could make in added fuel mileage.
If it was a lighter F100 you might could gain a little with a 302 but I just don't think you are going to be happy with the results in a F250.
I would take the money you would spend on conversion and buy a small well used economy car and drive your truck on weekends.
 
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Old Dec 2, 2010 | 09:56 PM
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Keep your F250 the way it is for hard work and get you a F100 shortwheel base with 302 with all emissions equipment working and engine completely stock. I get about 21 mpg out of my 73 F100 on highway. If you want better mpg than that you probably better find a little diesel car.
 
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Old Dec 2, 2010 | 09:59 PM
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You shouldn't have any issues reading the fuel gauge. As long as the selector switch is on the real tank it should read accurate. If not, it's not due to the missing tank, most likely a sending unit/gauge problem. I also agree that going down to a 302 would prolly hurt more then help.
 
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Old Dec 2, 2010 | 10:04 PM
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I had the 400 in my 77 highboy tuned pretty tight, and it got around 9-10 mpg average. My buddy's 07 3/4 ton 4x chevy with the six-oh barely manages 12 mpg on the interstate. If miles per gallon is what you're after, don't drive a heavy duty behemoth. If it's smiles per gallon, then by all means.

-Jared
 
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Old Dec 2, 2010 | 10:17 PM
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2x with 79FordBlake... a light(er) shortbed, highway gears, and well tuned engine will garner decent mileage. I don't drive the F-Bomb for mileage - I drive it to instill fear in those who see it coming down the road. For mileage, it's the PT or 68 Stang.
 
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Old Dec 3, 2010 | 10:31 AM
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their are things to help.

run skinny tires not wide. keep engine tuned up. I think a decent 400 should get around 14mpg if tuned up properly with 4 speed or c-6. if big tires and lift and other cool factors are involved it takes away from fuel mileage. these rigs aren't design for mileage. But if wanting to spend some money you can upgrade a c-6 tranny to some modern componets and it helps a little. Or upgrade manual tranny to s5-42 zf tranny. It helps some but their is some expense. Also running lighter weight/synthetics oils. their are many tricks to help but not totally solve your problem. What have you done to your truck to cause your fuel problems. I know of some engine upgrades to help a little like a modern ignition is a big step. Having a multistike ignition helps on the start up and helps your engine run cleaner at lower rpm's where we run ours the most. It helps a little. catch you later and any questions PM me!
 
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Old Dec 3, 2010 | 10:47 AM
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It costs a lot of money to save a tiny bit of fuel. Now days, with the cost of gas, these old trucks can't be your main source of transportation unless you are a millionaire. Driving technique is the best thing to change. Light acceleration and lots of coasting. Use brakes as little as possible. Don't idle. It will **** off all the impatient drivers out there which is pretty much all of them...lol.

I had a reg cab 4x4 long box 400cid 4-speed 3.50 gears 14 mpg. Now I have a SC 4x4 long box 400cid C6 4.10 gears 12 mpg. These are highway 60 mph numbers. Hope this helps.

fyi, 400 is considered a small block.
 
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