You might try a search in this thread to see if there has been any post about 460 EFI

 

Best mods I know of is replacing the exhaust cat back and adding any 5.0 TB. After that your better off with older heads and making up your own injection system or aftermarket TBI.

 

I'm glad to see great sense of humor. And your right.

He could keep it parked to and that will improve the mileage. (LOL)

 

Intuitively we all know why we want to improve gas mileage. Save money, right?

Well, if I get 6MPG on my 460 and I improve the MPGs by a mear 5% to 6.3MPG, and gas is $2.859 per gallon, I save about $22.69 for every 1000 miles I drive.

So, if you only drive 1000 miles a year some of the suggested improvements are not economically justifiable, but if you drive it 30,000 miles a year (like I do) then your savings would be about $680 per year for a meager 5% increase in MPGs.

If I could improve my gas mileage from 6MPG to 7MPG I would save a little over $2,000 per year in fuel costs. If I spent $500 to get that extra 1MPG it would pay for itself in 3 months. Not a bad deal.

Please keep discussing this issue and suggesting any and all ideas for improving gas mileage on a 460. It doesn't cost me much to read the threads and it could save me a ton of money.

 

Well one of the first thing I did was to go to a smaller carb from the factory holley I had on mine.I went to a Edelbrock 600 Cfm. Now I plan to change my gas tanks I have dual tanks but will go to a single rear tank by getting a 38 gallon tank from LMC. After that I can add headers with true dual exhaust. Also I plan on a AOD swap from my C6 which with all that done and my current gear ratio(3.55) I hope to get a solid 10 MPG on a ragular basis. But I haven't heard anyone talk about the grade of gas they are running?

 

Good math on the "not worth it if you drive 1,000 miles a year".

With the price of gas so much higher than it has been though, the break-even is faster than it used to be.

I've got the same truck... 460/5-speed/4wd/extended cab/4:10 gears. I got 11 mpg driving across Kansas with it... at 80 - 85 mph. I was getting closer to 14 though when I drove at 65mph, so I think your 12-14 should be realistic, provided:

-You are talking all highway. My above mpgs were entrance ramp to exit ramp, gas station, repeat. No traffic, no idling, no redlights.

-You aren't trying to make it from Denver to Pittsburgh in 28 hours (I slept for 5 hours and still avg'd better than 60!).
-The truck is empty. Weight kills mpg

While these trucks will really GO with a 460, they'll go much further with a light foot. If the tach clears 2200rpms you're wasting fuel.

 

Since when did the stock 460 come with other than a 600CFM carb? Unless you had one of them Motorcraft things and I'm not sure they were bigger than 600.

 

Mine didn't come with a 600.I put a Edelbrock 600 on mine cause every rebuilt factory motorcraft holley's leak.Even the ones from Tomco were bad after going through 3 of them I went and bought a Edelbrock and haven't had a problem since.

 

The stock Holley's (or if you prefer Motorcraft Holleys. Made for Ford/Motorcraft by Holley) were all 600CFM carbs. If it was something else then someone changed it and it wasn't a Motorcraft Holley. If a Holley carb leaks after a rebuilt it is poor workmanship and not the carbs fault. Besides why buy a carb rebuilt by someone who doesn't give a rats a$$ how you truck runs? Do it yourself and have it done right. If you can swap carbs, you can rebuild a Holley, which can't be said for the Edelbrock; which is actually a Carter carb from back in the 50s and 60s, so don't kid yourself into thinking it is a new carb design, He!! the Hemis back in the 60s came with a pair of them and they were noted for the carb fires.

 

I never said it was a new design but a new carb.For what I use my truck for it works fine.

 

I have an Edelbrock carb on my Mustang and love it.

What that has to do with getting more mpg's out of a truck with fuel injection is beyond me though, and well off the topic of this gentleman's question.

 

Well in the original post he never said if it was efi or carb'ed it wasn't until page 2 that he let everyone know it was efi.

 

Huummm I put a bigger carb on mine and got better economy and mo ppower.

 

What did you put on?

 

Holley 750 mechanical secondarys with a Pro Form body. Had the carb from before. I ran a 600 and a 650 they just didnt work out towing my 14000lbs boat. Economy sucked with them too. I would recomend a vacuum secondary 750 ovr the mechanical. Being frugal I just grabbed one off my shelf. Cant say it would be best for your combo + it wll have ported heads before winter I hope. Got to finish this hipo Nailhead moter and sell it first.