Hi Folks. I am looking for ways to get better mileage with my 1975 F250 Supercab 460 cu.in. automatic. Am thinking that a rad fan with a clutch may help. Any advice would be gratefully recieved.

 

The fan might help alittle bit, but I don't think you'd see to much saving at the pump the cover the cost of that fan. That 460 probobally won't get much over 12mpg, but have fresh oil, new air filter, and other little things like that if they're getting old.
Other wish there would only be 2 other ways to see a difference. Keep tires properly inflated, for less friction.
1) You could regear, if your gear ratio is to high(numatically) with the right size tires to match.(pretty expensive)
2) Let off of that big right foot. Acceleration kills gas mileage. Take it easy in low gears, and don't fell you have to be the first one to go after a red light,(swallow your pride and just slowly get it going and keep that up for a whole tank, and if you don't already do than, then I can promise you a 2 mpg increase.(free, just take a couple seconds off of your trip, but save you cash)

 

It's SO hard to keep an easy right foot on the gas in my 73 Ford. I'm getting about 7-8mpg average on my first tank since getting the truck running...probably because I have a lead foot. But it's really fun to drive and it hauls A$$!

Dan

 

I'm in the process of building a 74 f350 with a 390 and am trying to get the mpg up, right now it's a c-6 with 3:54 gears. I've been collecting parts to convert it for mileage. the plans are

1)4 speed standard, have this, looking for the clutch linkage
2)duraspark ignition, just bought distributor,module,cap,rotor,wires,plugs from Carquest for 200 bux
3) radial tires, have these also

At present it gets 10mpg, . The mods will be done one at a time, so I'll post any improvements at the time.

 

Yeah I plan on upgrading to duraspark, getting rid of the stupid points! Good to know you can get that from carquest for $200...not too bad! Should increase my gas mileage somewhat...hopefully!

 

The only thing you can't buy is the harness, gonna have to find that at the boneyard. makes for a nicer instalation, you can steal it out of pretty much any duraspark car or truck.

 

Thanks for the tips! Have recently upgraded my exhaust system to a duel 3 inch with Xover pipe. Should be a big improvement as the factory had two 2 inch leading to a common muffler w/ one 2 inch tailpipe. The power is quite noticable but haven't tested the mileage effect.

 

Read my post about mileage on this thread.

https://www.ford-trucks.com/forums/s...d.php?t=102632

Post #17.

 

I've heard great reviews with these people and their carbs for gas mileage increases.
http://www.ponycarburetors.com/

 

There are dual port intake maifolds which are listed as increasing gas mileage. I don't have first hand experience with them, so I don't know for sure if it actually helps.

Maybe someone who has used one can back up the claim.

 

You've got to give to receive. Fuel mileage is a trade off between cost of parts, and miles driven. If your truck is a daily driver to the office, park it and get a car. If you only use it for weekend camping and hauling, just keep it well tuned and everything adjusted properly.

Now, if you use it for a lot of hauling, there are things you can do to make it worthwhile. Dual 2 1/2 inch exhaust is one thing. New cam with dual plane intake and 600 cfm vacuum secondary carb will help a little. Note: if it's a hauling truck meant to haul things around on the road, you DO NOT need a big carb. Period! Probably the most noticable thing for gaining fuel mileage is higher compression. Rebuilding the motor to about 9.5:1 CR will gain you in the neighborhood of 80-120 hp from a stock 200hp 8.0:1 motor, depending on the cam and intake. It really helps with the mileage. There are also way's to make the C6 better on mileage too. Valve bodies, shift kits, ect... can help get the power through the tranny, which in turn will help move the truck. This will also improve mileage. My '79 F-350 DRW 12' flatbed truck with nicely modded '71 429 gets me about 16mpg. The motor puts out about 470hp and the truck weighs 6980 empty. You can hardly tell when there is 5000lbs in the back. You should see the looks I get when I open up the secondarys hauling a load. I actually had a mid 90's F150 try and pass me when I made a left onto a road. I had it opened up, and I was pulling away from him while he was in the other lane trying to pass me. Anyway's, unless you plan on putting a lot of needed miles on the truck, it's best to just keep it mantained. The stock 460 is a ******* pig on fuel, coupled with the pigish C6 you are destined to have poor mileage.