MPG?? 351W

[Orangecrush]

Okay, I've got $40k (minimum) in my street bronco. After all this, it finally runs perfectly, sounds great, has tv/dvd/gps.....everything. It's pretty tough.

Now that it's "perfect" (until the next thing comes up), I'm VERY concerned about the fuel economy. I mean, 10 mpg is to be expected. The thing is, I'm seeing more like 4-6 !! I have the 23 gallong tank. I put 15 gallons in, and after 80 miles, it's getting really low again. This just can't be right??

Here's my setup. Any ideas or suggestions would be appreciated. I'm ready to sell it otherwise.

*351W with RV cam

*Aluminum intake manifold

* Speed Demon 650 carb

- Black spring so back 2 barrels shouldn't open until 3000 rpm

*C4 tranny

*highway gears (70 mph is like 2500 rpm)

*35" tires (BFG Mud Terrains)

What gives? Could 5 mpg be normal for this truck?? The motor doesn't blow smoke at all and runs strong; but, I suspect it's "well seasoned" as the compression seems a little on the low side. Still................5 mpg (average) on the street ??

 

[STLKIKN]

The speed demon and the C-4 are dragging down your mileage.

If you can run a slightly leaner setting on the carb you should increase mileage.

Check the float level as well, if you can drop it slightly, you may find a bit better mileage.

With 35s you should be running a minimum of 4.10s to bring it back to closer to stock gearing, that will also contribute to poorer mileage.

 

[76Explorer]

If I had spent $40,000 on my Bronco, I wouldn't be worried about gas milage, I would be worried about a divorce /emoticons/[email protected] 2x" width="20" height="20" />

 

[NastyBad]

Not to bash, but with 40k (with mpg in mind) wouldn't EFI had been an obvious choice? If not, then why not switch. OEM EFI Ford setups are easy to do and very inexpensive.

 

[Bandit]

Not to bash, but with 40k (with mpg in mind) wouldn't EFI had been an obvious choice? If not, then why not switch. OEM EFI Ford setups are easy to do and very inexpensive.

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I'm not gonna comment about how much you put in your truck,I've got 28,ooo,and I could easily drop 40,ooo if I had it .Tell me exactly what gears you have?On the Bronco Driver Tire, gear selection chart,it shows a power and performance area and a good fuel economy area.You say you're running 35's....so...4.11'S and 4.27 gears put you in the highway driving,good fuel economy,and 4.56's and 4.88 gears put you in daily driver,best all overall balance of performance and fuel economy.personally ,I'd rather have the power,I'm running 4.56's with 35's,and I'm getting about 12 mpg.Have you tried an MSD,It claims to give you a more efficient burn of fuel,also,the tires you run definitely change your mpg,I was running swampers,and when I switched to MTR's my mileage improved.Also I went down in size on my carb,it still has power,but not as much if you're feeding more fuel.

!good luck,

BANDIT &lt