crown vic pi

A whole new engine sounds like a bit of overkill if you just need to replace a headgasket unless you think there's some warping or cracking going on with the block or head.

You need the intake tube, throttle body and elbow from the current motor and put that on top of the Crown Vic motor - the intake manifolds themselves are the same since you already have a PI intake. You may need to swap valve covers if the oil filler neck is on the wrong side and maybe some of the front accessories but it should all bolt right up. You'll need to drill & tap the intake for a second coolant sensor, or swap your current intake which presumably has already been setup for two coolant sensors.

It'll run fine without a tune but a tune would free up some more horsepower.

The water mismatch is the ports between heads and intake for the coolant crossover passage at the front of the intake. It's really not a big deal, a little RTV takes care of it. The PI intake wouldn't have anything to do with the headgaskets on your NPI block & heads.

If your '98 block is still healthy, you might consider taking the heads & intake from the Crown Vic motor and putting them on your the '98 block - that would give you a little more compression and some extra HP across the board. But, if you've got a lot of miles and you're concerned about the condition of it enough to replace the motor anyway, then you probably just want to stuff the CV motor in as-is.

Good luck!

The 2003 CV motor should be a Romeo PI. The lower intake manifold is the same. It's the upper intake that is different. The PI intake manifold from your old engine should bolt right up with NO issues at all (other than new gaskets).

An option is to re-locate the coolant temperature sensor to the block drain plug on the side of the block (near the freeze plug). But as Patman has already mentioned, your old intake should have already been modified as needed.

The CV uses a different EGR system. You will need to swap the exhaust manifold from the 98. Also suggest replacing the vacuum lines to/from the DPFE sensor. It is much easier while on the engine stand.

The fuel injectors are different. You will need to retain the injectors from the Mustang. Consider using an injector flow test/cleaning service such as injectorrx.com.

You will also want to retain the wiring harness from the 98 including the complete ignition system.

The hard heater return line is different. Suggest buying one a new one from Ford from a 1999-2001 MY Mustang.

The oil pan is different. If you want to retain the Mustang's larger oil capacity, consider swapping the oil pans. May have to swap oil dip sticks and pick up tubes.

Will need to swap the flywheel. Remember to get a new pilot bearing. This is a great time to resurface the flywheel (if needed).

Swapping valve covers has already been mentioned.

Consider getting new motor mounts (due to the age of the old ones).

Suggest taking LOTS of pictures of the old motor. Take from several angles before removal and during tear down. This saved me a ton of grief during my swap.

The routing of the front acc may be different. Suggest using the 2001 Mustang as a guide (belt length and acc routing). It may be necessary to add/swap an additional idler pulley (not positive on this one as my swap was a Windsor).

Patman brings up some good points. However, having pulled a Mustang motor myself, I would be hard pressed to say which is easier. Replacing heads on the car vs. the entire engine.

Performing engine work is much easier on the stand vs. in the car.

To me the most compelling reason for swapping the entire engine is the unknown factor regarding why the head gaskets failed in the first place. If the block deck is not absolutely flat, the new head gaskets are likely to fail.

Of course there is always a risk with a salvage motor.

Good luck.

PS: great post Patman!

heres what i did, i stripped my 05 CV motor down to the oil pan, valve covers, and intake. i then dropped in the car, unbolted all the fuel management components from the npi motor then bolted it to the pi engine. found the best way to adapt the passenger side coil to the timing cover, the driverside coil pack/PS resevior bracket bolted up just fine. i used the CV belt routing only because i didnt wana reuse/r&r timing covers, i then bolted my flywheel, clutch/PP and tranny up. all the A/C and PS pump bolted up no problems there. i installed my headers prior to dropping in the motor, sorry i left that part out. i used all my same TB/upper plenum and egr stuff off the npi motor. it works well right now. i had a couple pi intakes laying aound so i used the coolant neck from it. my temp sensor was already in the drivers head (only 05 and up has that luxury). mine had 34k miles and paid 750 for it, but i knew the guy. now its your personal preference on what you wanna do. me i didnt and dont regret it at all. my next thing is to get tuned. and the look on peoples faces when you pop the hood is priceless, ive had several OOOs and AHHs. oh my 2cents is DO IT YOULL LOVE IT. oh and also use the sensor out of the passenger side of the intake, if your not gonna use your pi intake on the new motor. if you are which i would btw itll make life easier.


awesome details mr. burns, and hats off to patman. sorry i had to add my 2 cents, but i did keep the CV valve covers, and i like the added hight to the filler neck, also its easier to pur in oil with the new neck location. my strut tower brace gets in the way of the npi covers. and to reinerate yes ALL the mustangs accessarys will bolt up to the CV motor.

FWIIW, the late model CV/GM's and Mustang's have a redesigned PCV system. It is what Ford calls "high interference" fit. The PCV valve is different different. The size of the vacuum line is larger.

Sooo. the CV/GM valve covers have the old style PCV grommet, they will swap. But, If the CV/GM has the high interference fit, then the differences in PCV pipe size need to be resolved. One way is to switch the TB to a 2001+ MY.

I suspect that for many it is easier to swap valve covers and retain the 98 PCV system.

To the OP, are you confused yet? Don't worry. It is not as hard as we are making it seam. Put both engines side by side. Just work through the items one at a time. They will work itself out.

Good luck.

Oh yea yea yea, I remember now burns. I wound up drilling the pcv hole a little bigger so the neoprine gromet would fit, DAH

To the OP I did mine in 12hrs with the help of my brother for about 7 of those hours

I wouldn't bother with the pi ecm, then your into swapping wire harnesses. Just keep the original ecm and get it tuned

Swapping a PI PCM into a pre 1999 is a much bigger job than you would think. The electrical system was re-designed in 1999 and as result, the number of circuits almost doubled. So MUCH more than the PCM would be needed (unless you are prepared to re-engineer the harness).

Much easier to get a tune.

I run a cobra shortblock in my car with 2v heads and everything bolt right up. you will raise your compression and it will pick up some serious torque.You will only be running premium, and will absolutly need a tune.

That would be a long block then, however its a good bit of work. Like modifying the wire harness, your coolant system, tune, etc

Then that's a long block. Short block id the block and rotating assembly. It is more work to do a 4v swap but is possible. You will have to use a 4v intake, I think the accessories are the same.

Their is no way you have to do anything with the harness. Only thing that's different is the knock sens. In the valley of the motor. But his comp. Won't pick those up anyway. The cooling system, he will just have to buy the 4v hoses and that metal thermestat housing peice that goes in between two hoses. And the IMRC delete plates that goes under the intake you can but from MMR. So I don't think it to hard minus the lighter wallet.

Warning. Scope creep ahead.

If $$ are an issue, I suggest that you get a firm handle on what does/doesn't come with your "deal" Cobra motor. The MY information is important. Remember, some ppl will try to pawn off a Mark VIII motor as a Cobra motor.

Not the say the Mark VIII motor is bad. But you don't want to pay for a Cobra and get a Mark VIII.

Not having an intake manifold is a sizeable OBTW. You are going to find they are not cheap.

What about exhaust manifolds?

IMO, it is vital that you write down your goals and outline your resources. Examples of resources are time, money, and expertise. The goals should be in order. IE, it is not possible to budget build with a 600 HP goal.

Start your project with eyes wide open. Do the homework. In the end, you will be happier with a complete 2v motor swap project than an UNFINISHED 4V swap (not to say you won't finish. But remember, not one single person has ever started a project intending to fail).

My vote is the pi heads on the cobra block, best motor 2v set up out there