67-79 F250 with modern engine swap is 15+ mpg possible?

Clutch

<---Pass
It may have been said already but a coyote motor would fit nicely.

I have thought of that too. I like the numbers of the Eco-Boost, 420 ft/lbs at 2500 sure looks nice...don't know if I want turbos, seems like more to fail in the future.

What are my manual transmission options with the Coyote? I see that Icon runs an Aisin-Warner AX15 in their Bronco...I am guessing that trans is too lightweight though.
 
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seanpistol

Explorer
it will get the torque and mileage I am seeking....for cheap too. Fits my old man just lug along driving style too. However...Nothing really beats the sound of a V8 gasser.

Except a diesel.

It would be a damn shame to put anything else in that truck.
 

Clutch

<---Pass
Except a diesel.

It would be a damn shame to put anything else in that truck.

The exhaust note does sound cool. You might be right on the "damn shame" part. What kind of mileage do you think it could fetch? 12V or 24V? I don't know too much about them. I have driven my buddy's 24V, it was impressive to say the least...IIRC he was averaging 18 mpg.
 

98dango

Expedition Leader
I used to get 18 mpg out of a 84 chevy 3/4 ton with 4:10 gears and 235 85 16. As long as I did not go over 65 I could watch the mileage drop at 68.

I drove from cody wy to Breckenridge Co and back so plenty of miles to verify mileage.
 

Clutch

<---Pass
I can see this thread turning into a gas vs. diesel real quick. :D :p


If I ever did buy a Travel Trailer in the future...diesel would make the most sense.

Maybe I need one of each...

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RedF

Adventurer
I didn't want to bring up the diesel option, since you initially stated you weren't interested. Sounds like you're coming around to the idea.

A 12 valve Cummins would be the ONLY diesel swap I'd consider doing to a 70s F350. Honestly, the 12 valve is top of my list for gas or diesel.
 

T.Low

Expedition Leader
I do think those old trucks look best in Midnight Blue.

945_main_f.jpg



I've seen that on google images . Luv that color and overall package, except the wheels and tires.

The blue would be sweet down in Tucson, not so much in the pnw. It will always look dirty and unkept from the rain, and then the pollen. In Tucson, you can wash it and it stays clean for weeks.

It would also show the northwest pinstriping too much. My van is scratched to heck from the trees growing over the trails, but from 20 ' away you can't tell.

Personally not a fan of the bling bling wheels: just my preference.

Quad cab with 6.6" bed is the way to go.


Speaking of diesel, my uncle in Flagstaff has a '13 Ram Quadcab long bed with 33.5" ATs , winch, winch bumper, etc, and his Cummins has 850lbs torque and is getting 19 mpg. Sure, with the initial outlay costs for be diesel you may never recover a return on investment from the added mpg...but I'm sure you realize that.
 
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Clutch

<---Pass
I've seen that on google images . Luv that color and overall package, except the wheels and tires.

The blue would be sweet down in Tucson, not so much in the pnw. It will always look dirty and unkept from the rain, and then the pollen. In Tucson, you can wash it and it stays clean for weeks.

It would also show the northwest pinstriping too much. My van is scratched to heck from the trees growing over the trails, but from 20 ' away you can't tell.

Personally not a fan of the bling bling wheels: just my preference.

Quad cab with 6.6" bed is the way to go.


Speaking of diesel, my uncle in Flagstaff has a '13 Ram Quadcab long bed with 33.5" ATs , winch, winch bumper, etc, and his Cummins has 850lbs torque and is getting 19 mpg. Sure, with the initial outlay costs for be diesel you may never recover a return on investment from the added mpg...but I'm sure you realize that.


I fricken love that truck...the wheels kill it, I wouldn't go any bigger than a 17" rim. IIRC it sold for $30K...still too nice for what I want to use it for.


The better half says do it in red so we can find it in the snow, we are moving to Idaho mid summer.

I plan on keeping it until the grave...don't care if I never recoup the cost.
 

Clutch

<---Pass
I didn't want to bring up the diesel option, since you initially stated you weren't interested. Sounds like you're coming around to the idea.

A 12 valve Cummins would be the ONLY diesel swap I'd consider doing to a 70s F350. Honestly, the 12 valve is top of my list for gas or diesel.

I like to be a little different...seems like everyone wants to drop a Cummins in. The smell of diesel just reminds me of another life I had...think it brings back nightmares. ;)

Might have to get over that. Really hard to beat the torque and mileage they get. Perhaps build up a crew for a hauler/camper...and a short bed high strung gasser for a play truck.

96aad3d962b214b35e42cdacf8083898.jpg
 
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RedF

Adventurer
I fricken love that truck...the wheels kill it, I wouldn't go any bigger than a 17" rim. IIRC it sold for $30K...still too nice for what I want to use it for.


The better half says do it in red so we can find it in the snow, we are moving to Idaho mid summer.

I plan on keeping it until the grave...don't care if I never recoup the cost.

^ That is a really nice truck overall. A couple of things I find strange though.
- All that lift without "better" steering. Crossover steering would have been a minimal investment.
- There's no hitch! Obviously they didn't intended to pull with it, but still!
- No tow hooks.
- That bed rug does not appear to fit well.
 

Clutch

<---Pass
^ That is a really nice truck overall. A couple of things I find strange though.
- All that lift without "better" steering. Crossover steering would have been a minimal investment.
- There's no hitch! Obviously they didn't intended to pull with it, but still!
- No tow hooks.
- That bed rug does not appear to fit well.

I noticed all of that too...makes you wonder what the bed looks like under the bed rug. Seems like there is always something weird the owner did with the restored ones.

Found this in Idaho...seems like most of the ones I have look at over the years have been in Idaho...funny that I am moving there beginning of August...maybe that is a sign. ;)


Over-all not bad.

I would change the front bumper, remove the steps, those flames have to go...not crazy about the seats either...

00202_jipzBz8RJSN_600x450.jpg
 

east_tn_81

Adventurer
I
I noticed all of that too...makes you wonder what the bed looks like under the bed rug. Seems like there is always something weird the owner did with the restored ones.

Found this in Idaho...seems like most of the ones I have look at over the years have been in Idaho...funny that I am moving there beginning of August...maybe that is a sign. ;
Over-all not bad.

I would change the front bumper, remove the steps, those flames have to go...not crazy about the seats either...

00202_jipzBz8RJSN_600x450.jpg

Love the Alcoa wheels.
 
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LR Max

Local Oaf
Get 15+ mpg? Possible but you gotta trim it just right.

This comes from getting more out of my old rover.

1st off, tires. I drop about 3 mpg going from 235/85/16 tires to 34x9.5 TSLs. I end up losing about 75 miles of range which sucks a lot. If you want to run 40" knobbys then no, you ain't getting 15 mpg. However if you keep it under a reasonable 33" and not 15" wide, then you are closer. Sounds like you want a street truck so going with a more reasonable size like a 265/75/16 or something like that will rock. Also on that note, reduce your tire/wheel package weight. A set of nice light street tires on some factory like alloys will be better than heavy carcass tires with dual beadlocks.

2nd, a good engine. Crappy underpowered engines don't do crap in the power nor MPG department. When I finally got my engine up to snuff, I noticed it held on the hills better, I wasn't using as much throttle, and I got better mpg. So yeah, if you are doing an engine replacement, get like, 400 hp. Also on that note, you might as well get a complete Chevy Gen 3 engine (like an LQ9) to throw in there. Good power, cheap, plentiful. I would say get a Gen 4 + 6 speed auto trans but you've already veto'd that. However a Gen 4 6.2 engine with the engine management (aka, cylinder delete) would help you out a lot on the highway.

Feel free to open up the exhaust and put a LS intake manifold on it but don't be going and throwing a cam and giant injectors in it and getting it tuned to the moon. Think efficiency and you'll get mpg and power.

If you put a carb on it, you deserve all the crappy MPG you get.

Be careful about putting a non-truck engine into a truck. They'll build their power at much higher RPMs. This is crap for a truck application and highway cruising. Also be careful of a LS1/2/3 used. That means it came out of a Camaro or Corvette...that was probably wrecked...guess what aluminum blocks don't like...

For gearing, set it up so you are using that nice low end torque. Something like an LQ9 will give you mighty fine power at 1500 rpm. So you can use that for highway cruising but not blowing up the gas tank. You said you want a manual trans, I'd look to see if a G56 would mate up to a Chevy engine. I did some research and you can get a nice new unit for like, $2k (if memory serves). This unit is great because you aren't going to be torque loading it (its for a diesel application so it should be able to handle a gasser without much issue) and its light. Same with a Gen 3 iron block, they are actually pretty lightweight and you'll probably be shedding weight by upgrading. On top of that, these old trucks are actually pretty light. Just think on the weight savings and it'll go a long way despite the fact the truck isn't aerodynamic worth a crap.

You'd probably end up running a 3.73 diff gear or something like that. This is alright assuming you start off with a transmission with a ~4:1 1st gear and your run of the mill stock chain driven transfer case. If you absolutely gotta have the crawl capability, then get you a 4.3:1 Atlas 2 speed but a chain drive will be great for street and help with your efficiency.
 

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