Ford 460

I recently bought a 95 F350 4wd dump truck with plans to use it as-is until I can find a 51-56 cab to put on it. The 460 engine was in rough shape, so I replaced it with a 460 from an 87 F350. It was an easy swap, and it runs great, but the fuel consumption is awesome. The best I have been able to get is 6 mpg.

Now for the details. The engine is stripped to bare bones. All the pollution control stuff has been removed-some by the PO, the rest by me. The tubes coming out of the exhaust manifolds have been removed, and holes welded shut. The air pump is long gone. I put a new electric choke on the carb, and the distributor is a one-wire unit from Summit Racing--basically a Chevy distributor made to fit a Ford. The high pressure fuel pump goes into a bypass fuel regulator with the pressure set very low. Specs call for 6-10 psi fuel pressure, but I have it set lower. Whatever was in the truck for a computer is no longer functional--one wire to the distributor, and a fuel line to the carb, and it runs like a top.

I haven't owned a Ford since my 55 crown vic in high school, so I have no relevant experience with Ford engines. Other than the obvious--replacement of all the computer controls and pollution control hardware- is there some significant issue I am overlooking which would improve my gas mileage ?

 

Make sure your distributor is calibrated for use on what sounds like a non-EGR engine.

Have a functioning vacuum advance that is appropriate to the pre-emmissions configuration of your engine is now in.

I don't remember what years; some 460s had the cam timing intentionally off(retarded?) from the factory. If your engine is one of those, even if you don't replace the cam, the engine will make more power and get better mileage if you replace the cam sprockets and chain with a "regular" ones.

 

Back in the '70's Ford retarded the 460 cams with the timing sprockets, for smog reasons, and they have been like that ever since. Get a straight-up timing set for a 429 and it will make some difference. So will a better cam.
What carb are you running, and what jets?
6 MPG out of a 460 4X4 heavy truck (I am assuming dual wheels?) isn't really surprising, it is after all a Ford.........

 

460 cubic inches is a lot to feed. That's a big motor by any standard. You can lean it out but you'll still have to feed it enough fuel to run right.

 

460's have never been what one would call misery on fuel consumption. My 85 F-250 Supercab with a four speed used to get a bout 12 and it didn't seem to matter whether it was just the truck or towing the race car. I traded it for an F350 Crew Cab Dually - that Pig got about 8, no matter what. It would tow my off road race truck up the side of a cliff but 8 was all it ever got. Both were 1986 models and the only difference was the weight and dual rear wheels
I imagine yours is even heavier!

I did put a cam that was designed for towing, an Edelbrock manifold, and headers on the dually and it improved(?) to about 10

 

It probably needs 38 to 40 degrees of total timing and that needs to come in by 2500 rpm that will help some.The late 80ish 460 were all strait up on the timing chain. Hope this helps.

 

Thanks all for the great feedback. I will do some investigating re: vacuum advance and timing. To BH-what do you mean "straight up on the timing chain"?? It doesn't sound like I will be able to get much better mileage, no matter what I do, so-o-o-o what does anyone think about replacing the 460 with a 351 ? I reiterate my almost total lack of experience with Ford engines. As a good challenge, I wouldn't hesitate to put in a 350 sbc if I could be confident that I could properly adapt the ZF5 transmission

 

I dropped a 77 460 that had been rebuilt in my 66 f250 and if I keep my foot out of it will get better gas mileage then the original 352,I dont know what all was done to it but it wants to run and hard to drive behind slow pokes. I presume it has straight up cam timing and maybe a RV type cam and cant wait to start driving it again since its been apart for body work and paint for the last couple years,the original 352 got about 10 loaded or empty and the 460 is definately getting better mileage then that.

 

here is a link on the cam i did on mine a few years ago

http://www.pirate4x4.com/forum/ford/807042-efi-460-cam.html

 

Melling Cam MTF3

Part Description : Torque Camshaft
Opens : -5 BTC/44 BBC
Closes : 29 ABC/-10 ATC
Duration : 204/214
Opens : 29 BTC/77 BBC
Closes : 73 ABC/35 ATC
Duration : 282/292
CamLift : .280/.295
Gross Valve Lift : .485/.516
Center Line C/L : 112/112
Rocker Arm Ratio : 1.73/1.73
Valve Lash Clearance : HYD./HYD.
Qty : 1
SHORT NOTES

Autolite 4100 Carb, 6" power valve

38 total at 2500
10 vacuum

Dual exhaust w/balance

 

HE-HE-HE!! I thought 6 was good, pull a loaded job trailer behind it, probably got 1, at best!!!-MIKE

 

In the early 80`s I had a side job of hauling a promo mustang around to some car shows for a ford marketing co. They had a 79 ford F350 with a 460 pulling a 42 ft trailor. I had the show car and my 69 Boss 302 in the trailor. The truck had 2 fuel tanks and would suck them dry in 100 miles!
460`s may run good but they are far from economical. You may mess around and get a little better but Id be surprized if you got past 10 mpg.

 

Had an injected 89 that would do 15 empty if I "allowed it to". Went to Carmel, CA from Det and back, towing a Packard in an enclosed trlr and averaged 8.6 for the whole trip at 17K lbs. Bought an identical truck and it wouldn't do better than 12. My advice? Convert it to a 7.3 Powerstroke and don't look back. We had one of those for the Alky F/C gig and did 16.8 loaded. Our wt was like 19K. Just sayin...