I have a 1995 F-150 300 Inline 6. I wanna increase the horsepower and MPG's. I wanna be able to pull a 19 to 21 footer. I need some more horsepower goin up the hills. Any help would be appreciated. Thanks

air in and air out
good clean air filter and high quality exhaust
19 to 21' is gonna slow ya down some, but learn to drive with it and get your speed up before going up the hills and use your momentum going downhill

I forgot to mention that its a five speed. what do u mean by air in air out? cold air intake? how much do those run?

Drop in a K&N air filter and keep it clean... You can modify the airbox for a "Do it yourself" cold air intake but not sure what your airbox looks like. Also, as FishHauler stated, add a good exhaust whether you replace the cat and muffler or do a complete exhaust kit... These to things get more air in and more air out which will increase HP maybe 5-10 horses... Also, tune it up, change the fuel filter and run some "Seafoam" through the tank 300 miles befor your next oil change and you will have that truck running awesome!! My buddy has that straight 6 in his work van and it hauls Bass!!!

Good Luck!

A cold air intake is not gonna help out that much.
Even if they make the advertized 10hp you will not feel it or even notice it on your mpg. I dont think you will need to do anything over stock unless you just have too much money and want to get rid of some. I would give the truck a complete fluid change. Oil, antifreeze, Transmission, differencial, and even purge the brakes.
Then i would put new plugs and wires. New FACTORY air filter. I have went the K&N route before and will not again. After doing alot of research they do not filter well enough for me.
All of this should give you 1-2mpg plus it all NEEDS to be done due to fluids breaking down.
If you are still having problems with the I-6 let me know by PMing me. I love these engines and have had a few before.

That motor is a good one...lots of torque. I had good luck with mine. I agree on staying away from k&n as well.

It's going to kill your MPG, but a lower gear ratio in your rear end is the ticket to pulling a larger boat.

"I wanna increase the horsepower and MPG's."

Often mutually exclusive goals.

i pulled my 20 with the same rig for years you can increase air and add a chip but your just gonna have to down shift on those hills

Exactly, more air means more horsepower, but not MPG's. More air means you burn more fuel.

how much does changing the gear ratio in the back end run? Im startin to realize that its gonna kill my MPG's so I just want more power!! Thanks

turn the overdrive off and give it he ll it will pull

anything if you hold it to floor.

The only economical way I know of to accomplish this feat is to get a new truck. Diesels are less expensive to upgrade torque/horsepower than gassers are. However if you get a new truck with a new powerplant, you will have more torque and HP, get a 3/4 or 1 ton if you are feelin frisky.....