Swapping From 98 4.6l To 99-02 4.6l

Discussion in '1996 - 2004 SN95 Mustang -General/Talk-' started by SadbutTrue, Dec 3, 2013.

  1. Brothers 98 GT 4.6L broke a timing chain, and he was told that's likely to have resulted in piston damage. My dad wants to swap in a new 4.6L. I have a few questions.

    Few questions:
    1) Is it true that a messed up timing chain will have likely resulted in internal component failure? I'm not sure on the exact driving 'symptoms', I'll have to add those once my dad responds. He has a service manual that says "broken timing chain = likely damaged internals" which is what he's basing this on.

    2) Are there any components that support a PI 4.6L that are different from a non-PI one? Here I"m thinking of things that normally wouldn't come with a new engine... the transmission bolthousing, exhaust manifolds, mounts, whatever.

    3) Are there any components on a PI 4.6L that my dad/brother should be sure come with the motor because the existing NPI equipment won't work? Google suggested the Mass Air Flow unit would be different. ANything else?

    4) What should he expect to pay for a 4.6L? I would think for either PI or NPI it' dbe in the $500 range for a used but running unit, and I wouldn't imagine much of a price difference these days between the two.

    5) Are there any advantages to the PI motor besides the extra 50 horses? My dad is mostly concerned with just getting the thing running, whereas I would never let an opportunity like this to swap in some power go by. It'd be easier to convince him to make the swap to the PI if it would be likely to prove more reliable (any internal components stronger) or maybe even help him pass California smog a little easier.

    THanks for the help!
  2. A pi engine is literally a drop in replacement, everything is the same. Exhaust bolts up the same, trans, everything. It will run totally fine on the stock tune. Its actually about 60hp.

    The only way to really know how bad the damage is, is to pull the heads off.
    Winters98GT likes this.
  3. Yeah there is a possibility off damage to the internals since it is an interference engine. Means if broken the valves and pistons can make contact. I agree with pull the heads and take a look.
  4. Yep, if you get a PI motor from a Mustang it's a direct bolt in minus changing your 98 front cover over to the new engine to accomodate the coil pack the 96-98 Mustangs used so get a romeo PI engine. You can use certain year crown vic PI engines also but will need to change the front cover and the oil pan off the 98. I have actually done this very swap. Very easy and very straightforward.

    However, Had it be to do over I'd go 4.6 3v