I have a 77 f-150 with a 460-it gets 10 mpg with 31 inch tires and 3.73 gears and a real light foot. I also have a 1993 mustang gt with a 5spd and 3.55 rear gears and it gets 21 mpg on the freeway. Big engines use big gas!! Anybody who gets 18 mpg with a 390 is a liar!! My 460 gets 12 mpg coasting downhill. The best mileage this guy is going to get is 9-13, at best! Anything else is bull!! Buy a Gear Vendors overdrive is about the only way your going to get any better mpg. That and change over to electronic ignition.

 

460 BB, I don't know who you are, but you sir are full of hooey. The 3.75 gear range is for I6s, not big power horses like the 460. You drop a 2.75 gear behind that engine and your mpg will increase. You are a lot like other big mouths with your clutch depressed, you are blowing hot air. Look at the torque curve of your engine, and plan it from there. The key word is planing, not just grabbing parts off the floor. My truck is strong from the start, but it's no dragster, but I don't drive from light to light. I designed it for crusing at 65 mph where it spends most of it's runnning time.
I'll lay 10 $100.00 bills on the hood of my truck, if I can't get 18 mpg out of it.

I have a 352, C6, 2.75 rears. Just do the math if you can, if you can't take your crap somewhere else.

John

 

>I have a 77 f-150 with a
>460-it gets 10 mpg with 31
>inch tires and 3.73 gears and
>a real light foot. I also
>have a 1993 mustang gt with
>a 5spd and 3.55 rear gears
>and it gets 21 mpg on
>the freeway. Big engines use big
>gas!! Anybody who gets 18
>mpg with a 390 is a
>liar!! My 460 gets 12 mpg
>coasting downhill. The best mileage
>this guy is going to get
>is 9-13, at best! Anything else
>is bull!! Buy a Gear Vendors
>overdrive is about the only way
>your going to get any better
>mpg. That and change over
>to electronic ignition.

interesting post, i think the gear vendors od is an excellent product, but i figure it cost about double what my truck is worth. no foolin.

 

WTG john, its nice to see somebody Deflating the Air heads that have posted here. I have a Similarly setup truck with a 390 and with a Inj Sys i get Somewhere between 18 and 20 mpg. And it runs alot better. the only downside is the cost, there are two ways to go, you can take a intake and have the injectors Mounted to it, and peice a Inj together (or let a copmpany do it Costs about 2200 Complete) or buy a Holley Projection System (avaliable from Jegs or SUmmit racing) Costs about 1300 for the top of the line 1100 for the next down.



Scott

 

I have been watching this thread for a while and have wanted to respond to several things but am abit afraid of getting chewed up. I can however tell you that in a 65 f-250 4x with 3:54s and 30 inch tires running a raceable 390( I say that because I use it in truck pulls and one year it won first in points for the season) I get 10 mpg consistantly towing or just cruising. I did not build the truck for economy. It is a work truck and I hate getting past on hills with a load. My point is fuel economy is realitive. I have been building trucks for 20 years and I live for FE motors, and currently have 2 CJs and a 427MR that are going into future trucks, but if it is mileage you want and still have the power to pull a sick ***** off a pisspot than go diesel. You can see my trucks in the photo section. My 65 is the white one with puller tires, and at the end of the 79s is my crew cab that now has a 7.3 Diesel and 5 speed. I got 24 mpg the first time I took it for a real test of all around driving, and I will lay 10 100 dollar bills on the hood If I am a liar. Rick. PS> I enjoy the disscusions, thats why I am here.

 

Gentlemen, I didn't come here to start anything. I will listen to what anyone says, and if there is a large hole in the bottom of your bucket I will say so. I have been proven wrong on this list, so I aint a know it all. I have owned the engine in my truck for nearly 30 years. My son did a four corner trash job with the truck that it was in. The engine then was good to get 12 mpg. I have known for a long time that if you drove the truck 45 - 50 mph, it got good mpg. You could make a sharp left hand turn and go up a fair grade and stay in high gear. The FE is strong and has a low rpm curve. If you are turning a stock FE over 4000 rpm, you might as well be pissing in the wind. I did the math and figured to get the mph up and rpm down, and good mpg would follow. Some of the 390s in the cars got 18 mpg, so why can't a lighter truck do the same, with proper gearing.

Enough of my rambling. Guys make sound statements and I'll listen, make foolish ones, and I'll tell you so. I'll try to address you statements and not make it personal, by calling you a liar.

John

 

i believe that 460BB is not comparing apples to apples.
john and i both have very similar vehicles. both are 352s set up for daily driving, not racing. i have an overdrive, john has a 2.75 final drive ratio. a 1965 f-100 2wd shortbed gross vehicle weight as stated on a texas title of ownership is 3500 lbs. my 65 is actually a little lighter than that!
460BB claims that a 390 cubic inch motor will not get 18mpg. he may be right as i have stated before that i think the 352 is a little more efficient engine than the 390. remember that we are a breed of truck owners that will tinker and fine tune when most average citizens will drive their vehicles as is until it stops running. that is why chris started this post and why we have expressed sixty-somthing opinions here.
a 460 is a 108 cubic inches more than a 352, it consumes more air and gas. it weighs more than a 352. a 1977 f-150 may weigh more than a 1965 short bed. and 3.73 gears w/out an overdrive is no combination for mpg.
18 mpg is not impossible from a 352 cubic inch engine, chris may never see 18mpg, but he may have a larger engine after all.
i actually thought about mentioning a bet which involved a certain 65 shortbed pulling a certain 1977 f-100 and still getting more than 10mpgs, but i restrained myself. seems you guys got all the bets covered.

 

First of all, I just read back through all the posts and I will eventually take my truck to someone that can actually look at it and what the problem is with gas milage. Also Id like to apoligize to jowilker because after a few of his posts my replies looked pretty snappy. I wasnt trying to be snappy but I think thats how it looked. My only concern now is finding the numbers on the block so someone can maybe id them. I would really like to know what size engine im running. Any help finding and IDing them would be appreciated.

 

> Thanks for responding, I thought everyone
>had given up on me. I
>know that there are alot of
>posts up here responding to my
>problem with gas milage and appreciated
>all the help. I was told
>on an earlier post to find
>the numbers on block near the
>starter, Are you talking about on
>the back of the block or
>on the side behind the starter?
>I cant find anything so please
>be more specific. This is the
>first truck ive owned and I
>grew up around a chevy family
>so I dont know much about
>ford motors let alone the FE
>family and neither does my family
>or friends so any help you
>guys give me is really a
>BIG help. Thanks again.

im sorry chris i think its real easy to get side-tracked on these posts. according to my sources, it is the block id # that is on the front of the motor under the oil filter housing. my info does not have all the fe block id #s listed, just the performance engines were listed.
how would you feel about a new post for the block id stuff, maybe that would get the attention of some hard-core fomoco parts id expert.
meanwhile, im still looking for your block #s i haven't given up, i have just run out of sources.

 

Chris, as far as I know thgere is no visiable number for you to decifer what you engine block is. As far as I know at this point you must remove one of the plugs, and get a small dowell rod and get an absolute bottom, and top measurement and mesure the distance between the two. The 390 has a longer stroke than the 352, and I think Thom Benedetto has the measurment on his site, if not check wrljet.com. We will get the cid if you get the mesurements.
I am not backing down from my statement that something is mismatched or the carb is dumping gas, if all is as you say.

John

 

 

chris, haven't forgot ya!!!!!! just been busy!!!!!! As 1 of the other posts says, the only version of the block # you found that I show is a 428!!!! If this is truly what you have, gas mileage is going to be bad unless you gear the truck for it. 2.75's would help the mileage greatly!!! Glad to hear that you are gonig to someone local. It is hard to diagnois w/out hearing it run!!! Hope this has all helped. The FE has alot of low end grunt, & higher rear gears can be run than if it was a smallblock. And someone says FE's can't get mileage???? That is bull!!!! I had a STOCK 76 F250 w/ a utility bed on it, 3.73 gears, & a granny 4spd., & it got 17mpg!!!! With some tuning & tweaking, they CAN get 18-20mpg!!!!!! It's all in the gears & how you build the motor.