So after seeing posts every week about this swap I figured I'd take the time to write up a sticky on how to swap one of these motors into any 99-04 GT.
1st thing to do is locate a motor. these motors were available in Lincoln mark viii's from 93-98. the ideal motor to find is either a 97 or 98 to swap into our new edge cars. the reasons are simple, they already have the COP ignition system, the intake manifold inlet is on the passenger side (if you opt to use the Lincoln intake) and supposedly the heads on the 97-98's are the best of the mark heads (earlier years are said to have the valves shrouded a bit, the newer ones don't but I can't confirm this either way) all you will need is the complete motor. no wiring, no PCM/ECU.
^This is the motor I used for my swap. it is a 43,000mi motor from a 1998 Lincoln Mark VIII LSC. picked it up for $400.
The next thing to do is strip all the Lincoln stuff off the motor that you can't use. so toss the motor mounts if they are still on there, toss the exhaust manifolds and the flexplate/torque converter (unless you plan to use an auto in your mustang) also, you will have to trim off the pipes on the back of the motor for the heater core. they are too tall and will in no way work with the mustang stuff. I cut them kinda low and used hose/hose clamps to hook up the lines to the heater core. these are the 3 optional things that can either be tossed or used. the 1st and biggest is the Mark intake. you can use that in your Mustang but a better-flowing and much better-looking option is a 96-98 cobra intake manifold. this is the route in which I decided to go. these are pricey (Look to spend $400 or so) so for a budget build most will skip this step. next is the IMRCs. you can wire them up with a nitrous window switch. Some people have done this with great results. I opted to delete them because it was easier (the 98 motor has plastic IMRC plates. just pull the rods/butterflies and JB weld the holes shut and you're done. Essentially a 'free mod') later on I plan to do a short runner mod to my Cobra manifold and give it some more timing and I will have almost zero low-end power loss.
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^A B head cobra intake.
The last thing is the fuel rail. the Lincoln is set up using a return line. our cars are returnless. you can either mod the return rail to work (block off the return line, add a piece of hose, a lot of butchery IMO) or what I did was picked up a Mach 1 rail and modded it to work. I don't know what would be involved with the mark intake but for the Cobra, you will have to cut the mounts off the rail and move the port on the rail for the fuel pressure sensor. you will need a TIG welder for this and some skills.
^port cut off, new hole drilled. next is to weld it up and pressure test it.
The next step is to yank out your old 2v. when you do, don't be so quick to get rid of it because you will need a few things from it before you do. keep your starter (the Lincoln one will work too, they are the same) keep your oil filter adapter block depending on the year of your mark motor (the earlier ones) your oil pick-up tube, and your 2v oil pan.
For the later motors (like mine) I needed an oil pick-up tube from a cobra because the tube diameter is bigger and the GT one won't work. All these will be swapped over to the 4v. I also found that I needed to swap over my 2v crank position sensor and cam position sensor. the plugs were slightly different from the ones on the Mark motor but no biggie, it's a direct swap.
^ Motor is out. I pulled the motor and trans together out the top. It's easy getting the motor out but wasn't so much to get the 4v in. I did the entire swap single-handedly so if you can get some extra hands and eyes, don't hesitate to take the offer!
now that the motor is out, get the 4v ready to go in. you will need to swap over your flywheel and clutch to the Mark motor. these are 6-bolt cranks so most GT stuff works. I used my stock flywheel (resurfaced at my Dad's work) and a SPEC stage 2 clutch.
^Picked this up with about 4800 miles on it for $135 shipped!
Next is to decide what you want to do for exhaust. You will need either a 4v mustang specific header or some stock manifolds from a cobra. any year cobra will work (96-04) I ended up going with a set of Ford Racing ceramic-coated stainless steel shorty headers for my swap. also, you need to make up your mind on the EGR. I kept mine and an EGR tube from a 96-98 Cobra is a direct fit. Otherwise, if you keep the mark intake, I would assume you could write something up with the stock Lincoln piece or you could just delete it and be done. either way, the choice is yours!
^ Got these new for $200. The best part is my h pipe bolts right up with no mods needed!
After swapping your 2v oil pan and oil filter adapter block onto the 4v, now you can put your transmission onto the new motor. any mustang transmission will bolt directly to this block. I used my stock flywheel and clutch (11" set-up from my 02 GT) and my Tremec TR3650 5-speed. once the transmission, starter, oil pan, and filter block all are swapped you can put your mustang motor mounts on and start to put the motor into the car. I used solid motor mounts from blue oval industries eBay store and I also put some of the wiring on before I put the motor in (the thick stuff that runs from the battery to the starter)
^4v is all ready to be dropped in.
Once the motor is back in, it's all downhill from there. hook everything back up that you can ( i only had 3 things that I had to make a change to in order for it to work) you will need to extend all of the COP wires and reverse the polarity on them. some people will say you can use the 4v boots and springs inside the COPS on your 2v stuff but I tried this, wasted a lot of money on it and it never worked right anyway.
Just do yourself a favor and wire them up the right way the 1st time using the 4v COPs and pulling the wires out of the end of the plugs and flipping them that way. the only other thing is the IAC wiring. that just needs to be extended like 12" and that's it. Real simple.
Lastly is the alternator. For this, you will have to go to your Ford dealer and get a repair harness for the Lincoln alternator. Once you have that, splice that into your stock harness. I screwed mine up the 1st time and had a battery light on in the dash and had to flip the wires around. That's it for the wiring, those were the only 3 things I came across so that isn't that bad at all. The worst part is the COPs - 16 wires of fun there.
I just got done dropping the 4v in. as I said, get all the extra eyes and hands you can! getting it to sit down on the motor mounts is a PITA. you WILL have to remove the trans cross member or you won't ever get the motor in.
Now go ahead and hook up all your coolant/radiator lines. I found I could re-use the upper radiator hose I just had to cut a bit off of it. awesome free mod there haha. Don't forget the heater core lines in the back either. now when you get to the lower radiator hose I ran into some problems. 1st is the 4v elbow was too short and the second is the sizes on the t-stat housing and lower radiator outlet are different. you will need a piece of your lower radiator hose that was used on the 2v and you will need a 96-98 cobra lower radiator hose.
I used a piece of electrical conduit and some high temp RTV to splice the two together and make one hose. that has been working for me since day 1 and I have no worries about it. your cooling system is only under 17psi and look at that coolant cross-over tube ford uses. no reason to worry IMO. hook up your clutch cable and your throttle cable. and as a side note, if you go with the 96-98 cobra intake, you will need a 96-98 cobra throttle cable too. these however are obsolete from Ford so you will have to get a used one if you are lucky enough to come across one. I got mine for $55/shipped but have seen them go for as much as $100 so be prepared to spend a lot on something seemingly stupid.
If you use the Lincoln intake, I'm not sure what cable to use. My 1st guess would be the stock Lincoln one but I can't say for sure. Either way, the stock GT cable won't really work. I would like to maybe see if a newer style cobra throttle cable would work but haven't had the time/money to do so lately. To have this thing run properly you will need a tune if you used the 24lb injectors. I have heard of guys using their stock 19lb injectors/MAF with zero issues at all so if a tune is out of budget then this may be your best option. I ended up going with the 24lb injectors, an 03 Cobra MAF, and a good E-Mail tune from Rick Erdman at Amazon Tuning Solutions.
So there it is. Hopefully, a Mod will Sticky this thing so we don't get this question coming up every week lol. anything further doesn't hesitate to PM me as I'm sure I probably forgot about some little things here and there.
