Hey guy's. I'm new to the board and this is my first post on a truck board. Spend most of my time on the Yamaha FZ1 board.

I ahve a few questions if you don't mind helping me out a little. I ahve two 98 F-150's. Actually one is mine and other one belongs to my youngest son. Mine has 140,00 miles ans his has 120,000 miles. We are both looking to do what we can to help them operate at their best. We both have duals, but not true duals. Mufflers are one in and two out. They were that way when we bought them. This brings me to my first question.

Will true duals help much. Power / MPG
Would we be okay leaving the stock manifold or would the cost of headers be worth it?
Does a cold air intake help much?
Which would you do first. I always thought it was better to let it out before you could stuff it in.

I grew up tinkering with cars, trucks, and motorcycles, but this new EFI stuff is all new to me.

Any help appreciated

 

true duals wont really do anything, i didnt notice a difference when i changed mine, it was just louder.

 

Thanks! Anybody tried headers? My main concern is I'm not getting the MPG I had expected. I'm only getting about 13. Is that about normal for the 4.6? Everything else seems to be fine. Doesn't use any oil, new plugs, wires, air filter, fuel filter. Runs fine.

 

Gearing would help both power and mpg. 4.10's will help around town because the engine will not work as hard to accelerate and with OD, highway mileage will suffer little.
Oh, and welcome to the forum

 

I would steer clear of aftermarket mods....Cold air intake etc,I installed a K&N filter in my 97,,and the mileage actually went down a bit....Im averaging around 17/18 with the LWB,4.2 V-6,Auto....Keep it as much OEM as possible..

 

Anybody have an idea why I'm only getting a little better than 13 mpg. I don't drive really fast. I don't take off like a rocket. I actually drive fairly conservative. I run the low grade of gas. Do I need to step up a grade?

 

I figure your mileage is about right for the engine size,and miles showing.The 4.2 in my 97 gets fairly good mileage until the air conditioner is turned on.Wish I could give a few good ideas,but as I said earlier aftermarket mods will usually tend to give poor results in the economy area.Just be sure the plugs/wires,and filters are in good order.Of course if you decided to do a complete rebuild,the compressions would go up,spunk would re-emerge,and mileage would quite likely be better...for my money its not worth the expense