f150 successful mods

[JR1]

Here are mods that improved gas mileage on my 2000 f150, 4.6L motor and 5 speed manual :

I installed a k&n filter with the FIPK long tube and a helical throttle body spacer when the truck had about 20,000 miles on it. Gas mileage improved by 1.5 mpg. Engine respose and power increased noticeably. That was 100,000 miles ago and the fuel savings have been constant. I don't think there is anything magical about the K&N filter-it was the FIPK tube , removing the old restricive airbox that did the trick. Any decent large cylindrical air filter on the end of the FIPK tube would work.

I also installed a Gibson exhaust about 2 years after the FIPK tube- no measurable improvement in gas mileage or engine power.

I've also found that a hard tonneau like a roll-n-lock is about 0.5 mpg better than a canopy.

In a back to back test, I found that the 5 speed manual got 3 mpg better than the same truck, same engine but a 4 speed automatic. Downside : you lose a LOT of towing capacity with the 5 speed manual.

JR1

[Frank Lee]

Claiming reducing intake restrictions as a fuel economy measure doesn't make sense.

[JR1]

Well, it might not make sense theoretically, I'm just reporting on how it improved gas mileage based on careful measurements and averaging over many tankfuls. Removing the constrictive airbox did increase gas mileage, possibly by allowing the engine to run properly, up to the air/fuel specs it was designed for. Cars get poorer gas mileage as the air cleaner gets dirtier, then recover to their former gas mileage when the air filter is changed.

[Frank Lee]

Not efi cars.

[t vago]

Originally Posted by Frank Lee

Not efi cars.

link

[markweatherill]

I think the throttle body spacer was the biggest factor, if anything. Not because of anything inherent in a 'helical' design, though.

(as for intake 'restriction', engines controlled by a throttle plate are, most of the time, running with a big old restriction on incoming airflow, by design)