I have a 1999 Expedition with the 4.6L. We use it to tow a camper and usually have plenty of power. However, last year we took the rig to Wyoming from VA and I was disappointed with the performance when engaging the headwinds in Nebraska, SD. This was due to drag on the camper face. We may be going back this year and I was looking for a cheap fix to boost hp. I was looking at the K&N Fuel Injection Performance Kit. Has anyone used this item or have any other suggestions within reason?

Thanks, Vince

 

There is no known cheap fix to boost horsepower. And sevaral testers have reported no gain in buying a big air deflector for the top of your truck either. Make sure your air filter is clean and tires inflated to a few pounds higher than around town or door sticker pressures.

I've hit those 40 and 45 mph headwinds heading west too, and got only 7 and 8 mpg towing 5200 lbs with 64 sq. ft. of frontal area. If your trailer is sort of boxy, the way most are, you might see if you fabricate and install a false front on it that is more streamlined to make it more efficient vs drag. And if the loading gate, taillights, etc. permit, you can add 12" wide extensions of the body sides and roof at the rear of the trailer. NASA showed in tests for truckers that trailers so equipped reduced drag at the rear and increased efficiency relative to drag by 5%. INcreased efficiency means more percieved power and better gas mileaage.

In Wyoming once, I had a fully loaded Mazda station wagon going into one of those headwinds for a camping trip and maxed out at 45 mph on the flat with my foot to the floor!

 

I know it's not a cheap option, but I have a 99 that I tow a TT with as well equipped with a 4.6L and am seriously contemplating a Kenne Bell Supercharger. From posts I've seen and mat'l I've read over the past few weeks it'll really give you what you need.... torque! It'll cost you about $4K for the kit and a complete dyno tune of your engine. This is a proven kit and it comes with everything you need to install it.

The second best item would be a costum burned performance chip for your EEC. I have a switch chip in right now that allows me to switch from an economy mode using 87 octane for daily use and a second switch setting for towing which uses 92 octane gas. It's not a miracle solution, but the right programmer should bea able to give you 20-30HP, perhaps more. Check out the performance forums below.

I've been researching this exact issue for some time as I can't swing trading up to something with a bigger motor, etc. And the Supercharger is by far the best bang for your buck. It seems like a lot of cash, but if you use it a lot it'll pay off. If you're like me and get stressed out driving in an underpowered situation the payoff is even greater since you can relax a bit more on your drive.

 

planning on adding a volant air intake ($250), gibson cat back exhaust system ($400) and may a chip/programmer ($300). i've been told that i can expect anywhere from 25-40 hp, 30-40 lbs torque increases. i'm very happy with my xp's performance but i'm hoping the mods will help me squeeze a few more mpg to make this worth my while. will let you know how that pans out.