Hey all! I have a 1989 F-150 extended cab XLT Lariat 4x4 with the 351. My dad just put it under my name cause he is tired of paying insurance for me now that i am 23. It is not in the best of running conditions but it still screams like a beast when in full throttle. I want to get it as close to original running condition as possible, but also want to throw on some goodies, such as headers and exhaust and maybe some cams. What would you guys suggest i do? Thanks
-Rob

 

Headers and exhaust is always a good starting piont for mods. When I did mine I noticed a bit of power increase but it also ended up running cooler too.
RSH

 

Nice, thanks, yeah i really want it to run cooler.

 

A free flowing exhaust always helps, with the 4x4 you might have fun installing full length headers. These engines do not like that radical of a cam change due to the restraints of the computer system. You could always switch to the mass air system.

 

Yeah thats why I was saying maybe cause i didnt know what all i could do to the 5.8L, what do you mean by switch the mass air system? Also how hard is it to install headers on these trucks, i think mine may have a 2-4" lift cause my dad bought it used in '95 and it is a little taller than my friends dad's '88, same truck.

 

The height seems to depend on what option you have, mine sits taller than guy I work with and he has a leveling kit under the front of his. The mass air system uses a mass air sensor MAS in place of the manifold air pressure sensor MAP, this gives the computer a better idea exactly how much air is passing through the engine. When you make changes that allow the speed density to pass more air the map sensor does not indicate exactly how much air is going into the engine. I am not sure exactly the modification needed to make the switch, others who have made the change will speak up shortly.

 

OK gotcha, thanks for explaining that