Mark 8 swap

I didnt think the Mark engines made any power? Are you wanting to use the shortblock?

The mark VIII block is the best 4.6L block made. Its an all aluminum Teksid made block, the same guys that cast Ferrari's blocks. Also it has 6 bolt main caps just like a cobra. The only problems is it did not come with a forged bottom end, it has the older b-heads on it and the intake manifold is not as good as the cobra's. Its a great all around engine for a cheap swap. You just need a cobra computer, wiring harness, and new plug wires. (IF your swaping into a 96-98 gt) Your 6 bolt flywheel will work. If this is going into 99-04 gt, you would be better off buying a supercharger.

tank_567 said:

You just need a cobra computer, wiring harness, and new plug wires.

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I heard that the GT computer can be flashed and reused by the person dyno-tuning the new motor..........any truth to that?

yes you can do that too, but its cheaper just to buy a used computer.

WAIT....... STOP.........
nobody move

that cobra computer is never gonna make that mark 8 motor run right i am in the process of doing the same thing if your gonna use the cobra ecm you need to change the heads (cams are different) injectors....and all kinds of poop

just keep it simple and use the ecm out of the mark VIII it works alot better and its tuned specifically for that motor
the only difference between what your doing and what i am doin is mine is a 99 V6
good luck and email me i will let you know how mine is goin also i am gonna post pics as it goes

hmmm. buy a sniper tuner and tune it for dyno time yourself. use you 97 GT pcm.

the tuner along with the 97 ecm is a good idea but wouldnt it just be easier
to just use the ecm from lincoln and be done with ....i mean just to get the damn thing on the road save a little more money back and then buy the tuner ....
i mean if ya already got both cars you got every part you need to make the thing run and thats the whole goal here right>???????

thats just my 2 cents but ya know to each his own everyone has a way to do things and everyone thinks that there way is the right way

whe i get mine done i am gonna make sure i write down every single detail
in case this ever comes up again and i might make an adapter kit for this sort of thing

1stanger1 said:

the tuner along with the 97 ecm is a good idea but wouldnt it just be easier
to just use the ecm from lincoln and be done with ....i mean just to get the damn thing on the road save a little more money back and then buy the tuner ....
i mean if ya already got both cars you got every part you need to make the thing run and thats the whole goal here right>???????

thats just my 2 cents but ya know to each his own everyone has a way to do things and everyone thinks that there way is the right way

whe i get mine done i am gonna make sure i write down every single detail
in case this ever comes up again and i might make an adapter kit for this sort of thing

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how do you plan to use a eec IV processor from a 95 mark 8 in a 99 mustang that is obd2.. the modules in your 99 are networked your going to have problems with your pats, cluster and abs...

Are you going to swap to a older cable driven cluster or are you going aftermarket?

You can make it work in your car but I think it might be cheaper to just reflash instead of dealing with getting the cars electronics to work

I think he would be better off reflashing the 97 gt PCM..

well i guess my point is: how is it hard to simply plug the 32v in and take 10 minutes getting a base tune, then driving to the dyno and spending an hour getting it perfect?

besides you can always write new tunes for major changes. like procharger, etc and dyno time is the only expense then.

its one thing to build a huge turbo with stock compression and stock bottom end and tune it yourself, and tuning a stock motor.

You can do it, ive looked into the research on this alot. It will be much harder than just a 4.6 to 4.6 swap. If i could find a wrecked Mark for under 800 bucks i'd buy it right now.

Heres the deal though, dont do it unless your going to build that engine first. Some guys talk about doing it just because their engine blew... thats the wrong idea. The internals are notoriously brittle, and your only going to gain a few HP over just going PI. But if your going to build the engine a bit before hand, or super charge it those heads are supposed to flow even better than the Cobra ones on F/I. And the block is supposedly one of the best ford made. If youve got the money to Port/Polish the intake side, drop some cash on headers and a S/C, and maybe do the internals it would be a great long term project. but just for a one to one swap its going to be a big headache and could potentially be costly.

That being said, heres what you need: to extend or split a few ignition cables, no big there, you will need a new bell housing maybe... since Marks are only automatics. Theres also some valves you have to delete, EGR i think? dont quote me. You will have to buy a cobra intake. Theres also another issue with the ignition that i cant remember, the mechanic i was consulting told me i may want to switch to coil packs and that would be much easier than dealing with the rest of it. Look it up on other forums especially Mark VIII derived ones like Lincoln Vs. Cadillac. Thats where i found alot of the info.

Other than those extremely vague hints that im sure didnt help much. It IS very possible and other than the above already noted problems its pretty much straight forward swap and drop. Ive even seen one in a Fox. ... It should run as you drop it in with your computer... or atleast start. Im sure it would not be optimum but its going to need a tune anyway, but a tune should fix the problem..... you wont need a wiring harness or a computer......

I was looking at putting one in my 04 GT and those were some of the problems, if your dropping it into an SN-95 you will have even less. Do a search for a write up on how to put a cobra engine into a GT to get a baseline. i used to have it but have since lost it. If i find it i will be sure to post it up on here.

Good luck man. And hey if you dont want that Mark let me know if its real cheap!

Whoops thats IMRC plates not EGR valves, and you may need a cobra oil pan aswell... i dont know if the GT master cylinder will have issues or not.

bell housing? i dont think so. the bolt pattern on the back of the motor is identical for autos and manuals.


the stock internals can handle 500rwhp easily.

and n/a they can handle 7k rpms. jim says he made 382rwhp with his with comp cams and pocket ported heads.


what cant take the revs are the stock valvsprings. beehive them, but it requires setem seals replacment and a little spotface for the 96-98 cobra/97-98 mark viii beehives.

use the mark oil pan.

if the mark oil pan is used what about the little reservoir on the side of the pan? its really in the way ......can it be removed?

billfisher said:

use the mark oil pan.

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1stanger1 if the mark oil pan is used what about the little reservoir on the side of the pan? its really in the way ......can it be removed?

i heard because of this you need to change it

i used a mustang pan for my swap.

NO BRAKES said:

i used a mustang pan for my swap.

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from what i understand the one from the gt will bolt right on but im not 100% sure. /////if you can get parts mark viii i would im stuck looking for ecm and air intake atm ! Cant seem to find one and im going to be using the 95 intake manifold(i hope) and because of that there are no K&N cold air intakes.

Shano2001 said:

from what i understand the one from the gt will bolt right on but im not 100% sure. /////if you can get parts mark viii i would im stuck looking for ecm and air intake atm ! Cant seem to find one and im going to be using the 95 intake manifold(i hope) and because of that there are no K&N cold air intakes.

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a regular 4.6 mustang pan will work. are you using a stock k member? i have the MM full k member kit. its a bit over kill, but its stiffer than an old dude on the blue pill

do your best to find a cobra upper and lower manifold. the mark manifold doesnt flow the best, and has firewall issues. i think i paid $350 for a cobra manifold.

NO BRAKES said:

a regular 4.6 mustang pan will work. are you using a stock k member? i have the MM full k member kit. its a bit over kill, but its stiffer than an old dude on the blue pill

do your best to find a cobra upper and lower manifold. the mark manifold doesnt flow the best, and has firewall issues. i think i paid $350 for a cobra manifold.

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Im going to look into that but from what ive seen so far theres not much for under 800 around me .
I really would like to get one. I plan on rebuilding the motor in a year or two and maybe eventually a KB. Me personally ill be using stock k member.