Tesla_HV

Hi all, I'm new here so please forgive me if this question has been asked many times. I did do a search first. Now to my question; if I want to replace the blown engine in my '96 GT with a 4V Lincoln Mark VIII 4V engine, I see that there was a mid '97 change. Which would be better, the early or late '97 engine for this swap. Also, is there a good internet article on this swap?
Thanks,
Monty

JC316

Check the guide in my signature, will tell you everything that you need. Any 97-98 Mark VIII engine will do fine.

1998Slow 'Stang

Ideally to do a mark VIII swap without buying the expensive cobra intake parts is to use the 97 or 98 engine, intake, and intake tube. They work despite the size difference in the intake tubes on the MAF end. (The mark viii intake tube has a much larger hole on the MAF end) This is cured by a 3" rubber pipe coupler from home depot for 4 bucks, and an atftermarket air filter and MAF flange.

If you stick to that formula, the hardest part will be the labor to it all. JC316's guide is awesome, and quite detailed. Both BlackMage and myself have swap threads in the General Discussuion section of this board, mine being the least detailed, covering for the most part what they didnt.

That being said, I found dealing with radiator hoses to be the trickiest. I got a 95 mark engine and swapped some parts from a 97/98 to it, so my thermostat housing is at a different angle than the cobra's, but the mustang radiators are slightly different than Mark VIII ones so mine is a bastard child of radiator hoses.

In fact, I used the stock GT hose, and some generic heater hose for the overflow tank, with, believe it or not, a water bottle top in the GT's overflow tank hose....so far so good? LOL.

Sorry if that got long winded. Let us know if there is anything else we can shed some light on.

JC316

Agreed on the radiator hoses being tricky. I also had a frankenstien hose setup. Think I used a combination of GT and Mark VIII hose, with a coupler in the middle.

piledriver

Hey guys, you all seem to know what you are talking about, so don't take this the wrong way, because I am ignorant in the matter. Isn't a Lincoln Mark VIII cammed different, and de-tuned, compared to a Mustang motor? You know, less power? Or do you guys do something to remedy that? Like I said, I am a mental midget about this sort of thing, so please enlighten me, and be nice,lol!

Tesla_HV

Thanks for the replies. I found a '98 VIII engine not too far from here. It has less than 70k miles so I might go and pick it up tomorrow. A couple of more questions if I could. I do not have a shop to working on it will be restricted to nice days in the driveway. That said, which way would you recommend swapping the engine; out of the top or drop the k-member and out of the bottom? Also, when I go to pick the engine up, what additional Mark VIII parts are critical?

As for the IMRC, the way that I understand it is that the IMRC keeps the runner to one of the two intake valves closed during low-RPM operation. Above a certain RPM a butterfly valve opens letting intake air into the second valve. Is this correct? If so, does disabling the system permanently open the intake air to both valves? How does a blocking plate accomplish this? What are the alternatives? The way that I understand it, the '96 GT computer has no control for this valve so if I use the IMRC, then I will have to come up with a tach threshold circuit which would control a relay. Is there a published circuit for this. (I am an electrical engineer).

One last question; I see that afterward a 'tune' is recommended. Where does on go to get a tune?

Sorry for so many questions I'm sure that I will have more.

Hey it's the weekend (almost).

Monty

jeh4269

Best way is to drop the engine out the bottom.You will have to do an IMRC delete.There's a rod that runs lengthways through the imrc's and has butterflies fastened to it.Take the butterflies off and pull the rod out.Then you either can weld the holes or epoxy them shut.You will lose some low end torque but will gain hp at higher rpm's.You will need a handheld tuner like an sct or diablo.Find a high performance shop around you to see if they can dyno tune it for you.I think the mark viii motors made 285 hp and the cobra engines made 305 hp.The major difference is the cams and the cobra has a forged crank.

jeh4269

Be sure to check out JC316's guide to installing a mark viii motor.Lots of good info there,I checked it my when I did my swap.You can also talk to uberstang(Keith),Blackmage(Will)and 1998 slow stang as they have also swapped 4v's into their GT's.The 4v revs quicker and will def be faster.

uberstang1

The swap itself is cake , u might have to fabricate some hoses and stuff with the mark 8 but a 4.6 is a 4.6 so old motor comes out new motor drops in, plug in wires and hoses and lines, tune, done. I can pull a 4.6 motor out of a mustang faster than a bum in a liquor store. Once u get past some emission and vacum lines, pulling a 4.6 is almost as easy as an old pushrod.

Tesla_HV

Well I ordered the '98 Mark VIII engine with 64k miles today. If they get the pull done today, I might be picking it up tomorrow. If so, I will post pics.
Thanks for all of the comments. It seems from the threads going so far, most have pulled the engine from the top. Having pulled many engines through the years, I can appreciate the simplicity of this approach. Does one have to pull the intake to get it to clear?
Thanks,
Monty