Hey guys, I’m having to swap the engine from my 98 F-150 due to bad compression in 2&6. Would a 4.6 from a 99 or 2000 Expedition fit? I’ve seen that the 99+ have the PI heads and my 98 has NPI heads but I’m not sure what kind of modifications it would require to make the expedition engine fit. Both my truck and the expedition are 4.6L Windsor VIN 6 so I know physically it should be interchangeable.

Thanks for the help!

 

yes but...
i would look to get a 5.4 pi motor... exhuast may need a bit of tweek 5.4 ports are 1 inch higher so i would get the exhuast manafolds from the 5.4 too or long tubes
should do it everything should be in same spots
only crazy difference in years is egr ports may not interswap
ie 98 intake needs 98 drivers exhuast manafold
and around 2002 started the drive by wire vs old school cable throttle
reuse all your 4.6 sensors and maf tps unless same part numbers or your ecu and dash may not be happy

i went the extra mile 5.4 Lincoln navigator 4v motor...
dash and ECU even the transmission

 

Lot more to it than you think.
I just changed a 99 PI engine and installed a 98 NPI engine 5.4.

(Forgot to add the exhaust manifolds are different as well)

Now I made my NPI a PI by changing the heads/intake from the PI engine to the 98 NPI engine. (That makes it go from 9.1 to 10.5 to 1 compression on a 5.4 engine NPI to PI )
Some 98-2003 expedition motor mounts cannot be used on an F150 truck. (Eddie B 98 will not fit) the f150 as they have a different pitch to them. The engine wiring harness, PCM/ECM is different on the expedition than your truck with the NPI engines, and the transmission in an expedition is either E40D or 4R100w and your truck should be a 4r70w. So you will have to change the flywheel on the engines to take what your transmission is as the E40D and 4R100W flywheel sets about a 1/2 inch more towards the trans than the 4r70w trans flywheel which will lock up your trans torque converter or bust the pump installing it.
The blocks are mostly the same, it is the heads and intake that are different from the block knock sensor, water temp in the head, and a few other things on the intake like the rear intake vacuum tube is longer than a PI one/oil sensor wire in the harness is shorter on the NPI as well.
The intake on an NPI lower intake has a switch that adjusts the air for the intake and the PI intake does not have this.
I was asking that question last year about changing engines and nobody knew the answer. Talked to those hot-rod mustangs people and they told me what to do.
Hope all of this helps. If you have other questions just ask me and I will try and answer.