My 98 4.6 died on me with 178k my mechanic says he has a 99 mustang engine with 90k on it . Is this good or should i stick with a f150 motor found a 98 with 130k . Is the mustang just a drop in

 

If your mechanic doesn't know if it would work I wouldn't think about getting an engine from him and I would look at getting a new mechanic

 

I just finished a PI swap on my 97 F150, which is a pretty similar project to what youre considering, so here's some info and a few pointers for you.....

Firstly, 99-00 GTs came with the Windsor PI version 4.6L 2V motor. The 98 F-150 is a non-PI 4.6L 2V; but could be a Romeo (VIN W) OR Windsor (VIN 6) version. Easiest way to tell the difference is to count your valve cover bolts; 11 = Romeo, 13/14 = Windsor. You can use the 99 GT Windsor motor in your 98, and you'll gain some power in the deal provided you make a few "tweaks".....

​​​​​​1) Intake manifold from a 01-04 F150 or Expedition 4.6:
Romeo or Windsor shouldnt matter because the intake ports and bolt holes are the same for all PIs. DO NOT use the Mustang intake on a truck. Although the motor components are pretty much the same, the truck intake is for just that.....a truck.
2) Your TB, plenum, and fuel rails that are on your truck now will work fine, but you would be wise to try to get the Alternator bracket that goes with the new intake, just to be safe. There are minor variations.
3) Water pump for 98 F150:
Mustangs have electric radiator fans
4) Coil Pack brackets:
99 Mustangs use COPs. If your current motor is a Windsor, you can just swap timing covers
5) Temp sensor/sender: (see pic below)
The 98s have one sender for the gauge, and a sensor for the PCM. 01+ use only one sensor for both, so there's only one threaded port on the coolant crossover. On mine, I made "TEE" to adapt to the new intake
6) Heater hose:
Use the 01+ hose for the front port on the intake. Rear hose is the same in both years.
7) Valve Covers:
You'll need Windsor Truck VCs, to make sure the oil fill cap and PCV port properly located.

I think that's mostly it. Please feel free to PM me for my contact info if you have any other questions. Ill be haopy to help!!!

P.S. I would definitely recommend the PI upgrade. Its only about a $200-$250 difference in parts, depending on what deals you can swing, but the boost in useable power is noticeable and well worth it IMO....
TEE for temp sensor and sender

 

Good info Boss!

 

Never said the mechanic didnt know if it would work ,WWhat i asked was what one i should go with

 

Thank you, Sir.....
I try to be helpful.