I'd absolutely love like a 3.08 gear in my truck. The E4OD has a low enough first that take offs would be fine, and you'd drop the RPM's so low in OD you'd probably save a lot on fuel. Plus 460's make peak torque at 1600 RPM so the lower cruising RPM's would be fine.

I work for my father in his trans shop and here lately he's been doing a little testing with trucks here and there. He's been putting F59D (low stall diesel) converters behind gas motors when we do rebuilds. He only does it for farmers and people who work their trucks hard, but it had me thinking. The lower stall point would drop RPMs down on take off and build up less heat. I'm thinking of trying this to see if I could gain even a little fuel mileage. We've had good luck with these behind the 5.8's, the low stall isn't good at all with the 5.0, but I imagine it would be great with a 460.

 

Actually if I think about it, I'm pretty sure the 460 converters are already low stall from the factory. But they just don't get the F59D designation from my supplier. I'll have to look more into this when I go in to work

 

My grandfather told me his 460 truck gets around 13. He said he does decent because of the higher compression, so it burns more and burns cleaner. Wonder how true that is.

 

i had an 89 cc lb and once i did headers, banks intake plenum, custom air filter nice plugs wires i was getting around 15 on freeway, but it was also 2wd, but it would out tow my pstroke, however it was stock, just drive it good and do a few fuel mods

 

Your dividing by 6 and multiplying by 8 is right on mathematically, but you'll get more accurate numbers to work with if you take it on a longer trip. If your GPS has a resettable trip odometer you can use that, or otherwise find a stretch of highway with mileposts. The longer the stretch you use the more accurate your numbers will be. For instance, with your numbers (6 and 8), if each is off by 0.1 miles it puts your actual distance anywhere between 259.0 and 274.5. On the other hand, go 10 times as far and you get 60 and 80 miles respectively and 0.1 miles off only gives you a "tolerance zone" of 265.9 to 267.4 miles.

And BigBlock350 didn't include your speedo calibration in his calcs. Assuming all of your numbers are accurate, you're going the 266.6 miles you said on 19 gallons which would be 14.0 mpg. But keeping track of how much gas you actually put in it would be more accurate too.

By the way, 14.0 mpg is such a good number you might not want to look into this any closer. You might find you're really only getting 10 mpg like the rest of us and you'll be less happy with your truck!

Edit: And by the way, if bigger tires is the only thing putting your odometer off, reading 6 miles when you really went 8 miles would mean that if your stock tire size was 235/85-16, you must be running 42" tires now. So I'm thinking something else is likely going on there more than oversize tires.

 

Screw it, I'm just gonna go with that I'm getting 10 mpg lol. I only use it to haul stuff, and I paid $800 for the truck. So I'm still in it dirt cheap even if I have to put a ton of gas in it. Right now, it's much much cheaper than buying/driving a diesel

 

So yesterday I got the "wild hair" I put the gas to the floor and the oddest thing happened… The truck physically slowed down, the speedo jumped up to 50 somethingish. And for some odd reason the rear tires seemed to be steaming. Oh and I can't forget the gas gage started to point to the unhappy E. On the plus side I do believe that I giggled like a small child during the whole process.

 

^^^^ That's what it's all about, haha ^^^^

 

This is a fun thread so happy new year to the big fords out there… I do love having an "older ford" The 460 is an animal and the truck looks like a truck is supposed to. Again happy new year to you all.

 

I just put a Hughes fuel miser torque converter behind my 460 and C6 transmission. It is supposed to add between 2 to 4 MPG because it is a closer to a 1:1 lockup. So far the engine does run cooler but I haven't been on a long enough trip to check MPG increase.

 

I have a 1974 460 in a 1966 F250 with a 1 inch carb spacer, headers, 3.54 gears and a Hughes fuel miser torque converter in the C6 and get around 12 MPG. Just bought a used US Gear overdrive and hoping to increase to 15 MPG. Only other idea I know to try is put a Dana 61 rear axle with a 3.07 gear. Any more suggestions would be appreciated.

 

I have a Gear Vendor O/D with C6 460 Std cab.lb. i get around 12 unloaded. I'd sure like to try the Hughes fuel miser torque converter also.

 

More recently I've come across a possible way to increase fuel economy on the EFI engines that can be tuned when using ethanol blend fuels, such as e10, e15, e50, e85, etc... While it's not all that common the few people who've done it claim a significant increase in MPG. What they do is tune their EEC to add more EGR. Most report a 4MPG increase on e10, and 6 on e85. How valid these claims are as far as the actual MPG amount, I'm not sure, but I can say that the claim of more EGR with ethanol creates a better burn is true, so it probably does increase MPG somewhat. More EGR also CAN allow for more timing, which usually equals more complete combustion, but more timing isn't always the best...

Any rate, /backontopic...

 

Wow! Very cool!

 

When I get my TwEEcer I'll give it a shot