Hey guys need some help on my 4v stuff

voidfinger · Sep 4, 2007

Hey yall, i have a 95 or so mark 8 motor coming in and i want to swap it into my gt. I need some advice on what i should do with it. I would like to know a couple things. I am interested in a 97-98 mark 8 intake, it looks like the 99 up cobra and since i'm not going over 6k will that work? Whats the difference between the mark 8 cams and the 96-98 and 99-01 cams??? i would like some specs on it and since i'm not going over 6k with the motor and 4r70w trans what would be the best combo. One more question, what would i have to modify to get it to work with my 98 gt wiring/computer? I would apriciate any help and any advice or stuff from anyone that has some ideas here and any one that has done the swap chime in please. thanks

Knuckles@Empire · Sep 5, 2007

well some of the differences in the two engines is the crank mark8 is cast iron, cobra is forged. mark8 in take manifold is made for performance up to 55oo rpm. you can swap that out for a 96-98 cobra manifold. as far as the cams dont have any info on thse ill keep looking for you. im sure your going to need a new harness or atleast to modify it and an probably replace the ecu as well, but im not sure like i said ill keep looking if you find anything let me know m interested in this swap for a future project possibly. goodluck.

uncltrvlnmatt · Sep 5, 2007

The major difference is the crank and intake like said above. The Lincoln Crank has an 6 bolt flywheel pattern and the Cobra has an 8 bolt flywheel pattern.I believe everything else is the same. I have a link to it somewhere I will try to find it for you.

19mustang95 · Sep 5, 2007

you can use the GT computer and harness, you have to get the GT computer tuned though and make some alterations to the harness.

voidfinger · Sep 6, 2007

DFG_Pimpin said:
you can use the GT computer and harness, you have to get the GT computer tuned though and make some alterations to the harness.

Yea i've heard about altering the harness, i just don't know what needs altering... I got a complete cobra wiring harness and computer but it won't support an auto and i'm trying to decide whether to keep the auto or go on and finish out the 5 speed swap and put it in with the cobra :-\ , but i got a set of "i think" 98 Cobra cams... anyone have part #'s for the cams? So i'm on my way

I've heard that the mark crank is better for N/A applications since it is lighter and spins up faster than the cobra since the cobra one has more weights??? is that right? thanks

Jrgunn5150 · Sep 6, 2007

There's one sensor that will be out of reach with the Mark VIII motor, just lengthen the wires.

The 6 bolt crank is probably a bonus, since you have a 6 bolt flexplate now. I don't know about it being "better", but it is plenty good for over 400 hp and 6500 rpm.

Can't help you on the cams, but I know the Mark VIII are lower lift, less duration.

You'll have to deal with the IMRC, I personally would just take it out and fill the holes myself. You can also buy plates, or try to wire it up to work with a MSD box.

voidfinger · Sep 6, 2007

yea i was thinking of just using a msn rpm switch, if i go with a manual tranny i have the cobra wring harness and computer so i might just use those and go with a 5 speed :dunno: