Hey guys. I have a 98 Expedition 4WD, 5.4L, 3" body lift, 33" Cepeks with 166K miles. I tow a 20ft enclosed racecar trailer on weekends. Well its starting to lose power in its older days so I want to either install a bigger engine or rebuild/modify my current engine.
Yes I would love to have a nice F250 but I want to keep my Expy for the following reasons:
ITS PAID FOR!, it fits inside my garage, its more practical for parking spots, its great for 4x4 fun. It just fits me better.

Anyway, I dont think adding a diesel engine will be easy so what are my other options? If I just rebuild my 5.4, what can I change to make it a beast?

 

You have a few negatives going right from the start. One, the lift kit with big tires. That is a strain on the entire drivetrain and robs you of power. 2nd is you have the non p.i. motor. 230 hp is not a lot for a 6K vehicle pulling a 20 ft trailer I assume is loaded on the weekends. That motor has got to lug around 10K when you tow and last is the 166K. A lot of miles but in no way ready to die. They last a long time but also with the few mods you have done and towing what you tow there is a good chance the engine is tired. How much money do you have and how much of it do you want to spend. That is the question you have to answer. Rebuilding it will only get you 230HP, still pushing with what you have. You may want to look for a p.i. motor from a 99 and up and get the heads from it and intake and other stuff. How about aftermarket cams with a little more lift. That would give a little hp when you need it. How about a tuner for when you are towing. I am sure if you search this forum, you will what others have done and what works and what doesn't. Good luck!

 

I'm aware of the negatives for my kind of setup, but you gotta pay for what you want right? I'm getting multiple uses from my Expy so I require more power. I'm thinking now towards a fuel injected 351W. I'm finding several nice high horsepower crate engines to choose from.

 

Your best course of action and most bang for the least buck is to rebuild the 5.4 and add a supercharger.

Send a PM to 04markIII for supercharger information. He put a supercharger on his 5.4 Expedition: https://www.ford-trucks.com/forums/member.php?u=336373

 

You might want to check out this site: Squires Turbo Systems - Bolt-on. A turbo will use the exhaust gasses that are wasted to provide a great horsepower boost. Squires has the system down pat, or you could install the V10 and then turbo it.

 

Superchargers are not cheap but add lots of instant HP.
STILLEN : Vortech 1997-2003 Ford F-150, Expedition, Navigator 5.4L 2V Supercharging Systems

 

Superchargers with the correct supporting mods can really wake these trucks up.

 

I think I may go with a supercharger. Sounds like a better idea. Though it sure would be cool to have a diesel in it.
Thanks for the advice.

 

You might get the same power with a turbo vs supercharger.. I think the turbo will get better MPGs during the week though (when you are not on it).