My 2001 F150's engine is getting tired with 100k very very hard miles on it. I was wondering if by chance anyone here could tell me what the difference between the two as far as motor mounts and actual dimensions. Is the 4.2 a bored out 3.8? I really like the truck and although it is rough it is very simple. No power windows or locks, radio just a 5 speed on the floor. Anyway anything you can think of will help me greatly.

PS i know it isnt a mustang... But I wouldnt mind putting a mustang engine in it.

 

the 4.2 is a stroked verison of the 3.8. the motor mounts should be the same. how is your engine getting "tired" at 100k miles??? unless you have had some poor maintenance. my 3.8 has 166k of hard miles and still going strong.

 

Upper intake is differnt as well. it's got better runners, but it is physically taller.

The 4.2L makes more hp and tq than the 3.8L. If you swap in a 3.8 in it's place, you'll feel the power loss alot.

 

Well, I got the truck with some really hard miles with not so good maintenance. I have thought about rebuilding the 4.2 and the 5 spd and possibly the rearend. I really like the truck but man does it run like ****.

I would rather swap in somthing much larger. All I really want is for the engine to start up, shift right and tight aswell as have all the guages work. I dont mind running aftermarket guages. If it could be done I dont even care if I have A/C. Just need my brakes/lights to work.

 

with putting larger such as a v8 you will have to swap alot to get it to run right(engine, trans, rear end, ecu and such). it would be alot cheaper to rebuild the 4.2 or find a replacement 4.2 to drop in.

 

You can find a good solid 4.2L for about $600-$800 that will drop right in if you have a free afternoon. That's the route I'd suggest.

 

Why not slap a M112 ontop and beat the snot out of it till it goes.
Just as a backup keep an extra 4.2L around.

 

Well, that sounds like a hell of a deal! rebuild the 4.2 and supercharge it. nice!

 

even better swap a low mileage 4.2 with an eaton already on top of it

 

More horsepower than the 5.4L guys and in a lighter more fuel friendly package.

300-350hp are safe numbers on an M112 swap, you can do it for around $2-2.5k.