Mark VIII 4.6 swap

[MarkVIII]

I'm sure this has been covered before - I've tried searching with no luck.
Anyways, I have a 2003 XLT 4x4 V8. I will also have a 32v 4.6 from a '97 Mark VIII LSC sitting in my garage. (was a spare for my '98 LSC - but I have decided to sell my Mark). Was wondering how easy it is to swap the engines? I already have a engine hoist and heated garage to work in. There's nothing wrong with either engine, and both are close to the same milage (75-80k). But increasing to 290HP vs the 240HP I have now is very tempting. I seen something about keeping the stock computer and fuel rails, and swaping the rest. Can it really be that easy?

 

[Limited02]

It's gotten about as far as you have....someone just asking. Since you have the motor, go for it. I don't know everything involved, what fits, doesn't, but you need to just go for it. You might even want to see what it will take to put the topend (heads,intake,etc) of the 4V onto your 2V. That way the motor stays bolted to the tranny and you don't have to worry about the torque converter not matching up or bellhousing being different. If I run across someone converting their 2V to a 4V, I will post a link. Good luck

 

[CDW6212R]

You can make a swap, but you will need many parts from an Aviator. The fuel systems are nothing alike, you have to have the later fuel rails, intake manifold etc. I think the trans would bolt up fine. Spend some time looking at the Aviator DOHC, compare the front dress and intake parts to your 98 DOHC. It probably will be much more expensive than you are thinking.

If it was worth the cost to you, I would rebuild the 98 shortblock and include later model heads also. I have the heads BTW. Good luck,

 

[Limited02]

It will probably be just as involved to do some kind of forced induction. I would go that route and sell the motor(4V) to finance the project. There are used vortech's and prochargers going for decent prices. I think those would be the easiest to adapt. Otherwise a kenne bell or whipple would be nice.

 

[Drewstang]

I'm planning the same type of swap, but you might want to consider a few things. First, the "B" heads on the Mark 8 4.6 do not have as many options as the "C" heads on 99 and 01 Cobras, 03-04 Cobras and Mach 1's, and the Avaitors.

Second, the intake on the Mark 8 is very restrictive when compared to the Cobra intake. At the very least, swap intakes.

Last, the Mark 8 and 96-98 Cobra have intake runner control modules that will not allow the second set of intake valves to be used unless you are over 3000rpm. The Aviator uses simular technology, but it can be turned off in the tune or bypassed by using a Marauder or Mach 1 intake.

 

[stang99x]

I have the a 98 mark 8 as well, just remember that engine is geared towards hp more than a truck, and you'd prob loose some tow capacity. The 98 cobra intake mod is a very popular swap, but its going to require egr tube rerouting. None of those intakes will fit on it afore mentioned though. Changing to the 99 cobra c heads gives you more options, but htere is still a great deal of modification involved. I'd just get an aviator motor. At the very least if you do do it, swap the mark motors crank out for a forged cobra crank.

 

[CDW6212R]

Yes, there are tons of various parts for the DOHC, from so many years and models. I was working towards building one before discovering it wouldn't fit the 98 Mountaineer. I got the 2001 heads before learning that the 04 Cobra had revised heads for cooling with the boost. Live and learn, go for it.