5.4? What does it take?

[AaronK]

What modifications would I have to do for a 5.4 shortblock in the 03 Cobra. Would the heads and supercharger fit?

Also, a friend of mine wants to run a n/a 5.4 2v motor. Would the 2v heads/intake work with that block?

 

[Ironhand]

Thats a whole bag of worms bro.

2V 4V it doesnt matter the 5.4 block is the same.

You will have to modify your lower intake to fit(Cut and widened) and you may have to make an adapter plate that will fit in between the blower and lower to make it fit the widened lower. You have to use a 5.4 specific timing cover but you must weld on tabs or make brackets to hold the secondary belt drive for the supercharger. The alt brackets must be changed as well and you have to mod the timing cover for the alt brackets to mount to it. Your exhaust location will end up moving up and outward alittle due to the taller deck height. Wiring harness as to be extended in certain places to make it fit(This is depending on a few other things though) You will have to mix and match various parts in order to make it work but it has been done before a few times.

Ask me how I know all of this....??? :thumbsup:

 

[GodStang]

Adding to what Ironhand said. A 2V 5.4L is an easy swap into a mustang. a 4V is not. CrazyDave or something like that makes everything you need to drop your 5.4L 4V into a mustang. To do a 2V you need intake adapters or new intake and headers and you are good to go.

 

[jcveron]

Godstang..do you know everything about these cars? You post on everything lol i bow to you cobragod

 

[CobraBob]

Aaron, looking at your current mods (in your signature), I take it you're just not satisfied with your present setup? Just curious because what you've got is pretty impressive.

 

[steve5575]

You might look into buying a used Navi engine and then a twin screw kit that was designed for that particular set up. Sounds like a nightmare of a job though. The Lightning guys were always begging for a 4v adapter to throw the Eaton setup on the Navi heads. This sounds like a similar issue that you would be looking at and you'd need a huge cowl hood. Sullivan was looking into making that Eaton adapter for the 5.4 block/4v heads. Not sure whatever happed with that.

 

[Ironhand]

Adding to what Ironhand said. A 2V 5.4L is an easy swap into a mustang. a 4V is not. Cobra Dave or something like that makes everything you need to drop your 5.4L 4V into a mustang. To do a 2V you need intake adapters or new intake and headers and you are good to go.

It's actually CrazyDave and he just recently had twins not to long ago so he is out of the game for a while. Birdman also made a kit but it was for the N/A version. I have talked extensively with Crazy Dave and from all the research I have done and information that we talked about I believe I know exactly what to do. But I will find out in December once Im home and then the build thread will be posted on here with a few changes of my own.

 

[Ironhand]

Godstang..do you know everything about these cars? You post on everything lol i bow to you cobragod

He has been in the game for a while now. But dont let him fool ya with the name. He's not really God. That is Sid297. :beer:

 

[GodStang]

Godstang..do you know everything about these cars? You post on everything lol i bow to you cobragod

I have had the my 03 Cobra for 5 years now. I work designing a Nuclear Waste facility for the government. So I have tons and tons of free time to do research. So reading just about every post on a bunch of different boards for the past 5 years on the same car you tend to learn a thing or two or at least be able to fake it a lot.

It's actually CrazyDave and he just recently had twins not to long ago so he is out of the game for a while. Birdman also made a kit but it was for the N/A version. I have talked extensively with Crazy Dave and from all the research I have done and information that we talked about I believe I know exactly what to do. But I will find out in December once Im home and then the build thread will be posted on here with a few changes of my own.

Oh yes CrazyDave. Keep us updated on your swap. I am about to do a 5.4L 2V swap in a 2001 GT and then a 5.4L 4V TT swap into a body left to be named. So I need to know what I will run into.

He has been in the game for a while now. But dont let him fool ya with the name. He's not really God. That is Sid297. :beer:

Hahaha. Actually my last name is Godbee and I drive a Mustang. So I put the two together. Godbee + Mustang = GodStang. I drove a V6 when I came up with the name back in 99. I just kept the name over the years.

 

[Ironhand]

I have had the my 03 Cobra for 5 years now. I work designing a Nuclear Waste facility for the government. So I have tons and tons of free time to do research. So reading just about every post on a bunch of different boards for the past 5 years on the same car you tend to learn a thing or two or at least be able to fake it a lot.



Oh yes CrazyDave. Keep us updated on your swap. I am about to do a 5.4L 2V swap in a 2001 GT and then a 5.4L 4V TT swap into a body left to be named. So I need to know what I will run into.



Hahaha. Actually my last name is Godbee and I drive a Mustang. So I put the two together. Godbee + Mustang = GodStang. I drove a V6 when I came up with the name back in 99. I just kept the name over the years.

Ahh I see. And I thought my name was weird. lol But!!! Im actually at a point now I dont know what direction to go with. Either 3.4 Whipple or Twins.. I have parts for the PD setup but Im also at a point where if I change the direction I go it wouldnt cost me any money to do it. And regardless the DSG(not the 10th) is getting a full Fore Return Style Fuel system. :rockon:

 

[Sniperdog]

Ask me how I know all of this....??? :thumbsup:

Someone told you :shrug: oke:

 

[97desertCobra]

OP it would be far easier and less expensive to get the Boss 5.0 block and a stroker rotating assmebly. That would give you 5.3L, which is very close. The Boss block is the same deck height as the 4.6 so your timing cover, heads and intake will all bolt up.

 

[Sniperdog]

OP it would be far easier and less expensive to get the Boss 5.0 block and a stroker rotating assmebly. That would give you 5.3L, which is very close. The Boss block is the same deck height as the 4.6 so your timing cover, heads and intake will all bolt up.

Now that's what I'm talkin bout :rockon:

 

[Ironhand]

OP it would be far easier and less expensive to get the Boss 5.0 block and a stroker rotating assmebly. That would give you 5.3L, which is very close. The Boss block is the same deck height as the 4.6 so your timing cover, heads and intake will all bolt up.

Not exactly true. A boss block un-machined is 1K. Plus rods and pistons alone is right at another 1200-1400, plus the cost of a crank, rod and main bearing etc... Considering I have less money tied up in my complete Shelby shortblock then the cost of your block, rods and pistons. You would be incorrect in your assumption.

Your idea is the easiest of the two, kinda, but I guess it depends on who you are really. To me this is easy only because I like to figure stuff out. There are pros and cons to every build. But if I wanted to I could do the same thing and bore and stroke the 5.4 and come out with 388 cubic inches and your long rod, big bore 324 wouldnt be as tough as the stroked 5.4. Also look at the valley on the 5.4 block, it is pretty beefy and perfer it over the 4.6 blocks due to rigidity.

 

[99 GT vert]

if you want to do the swap with out having to get your stock lower modified this might help you out a little. you could just get the lower looks a little pricey and shipping will probably be a bit since it is from australia

 

[Ironhand]

if you want to do the swap with out having to get your stock lower modified this might help you out a little. you could just get the lower looks a little pricey and shipping will probably be a bit since it is from australia

If you look at the pictures that is an 03-04 Cobra lower that HAS been widened except they did it and it will cost you 1400 dollars plus shipping. So why not pay for a 200-300 dollar lower, then pay a good welder to have it widened for you? And save 900 dollars???

 

[AaronK]

Thats a whole bag of worms bro.

2V 4V it doesnt matter the 5.4 block is the same.

You will have to modify your lower intake to fit(Cut and widened) and you may have to make an adapter plate that will fit in between the blower and lower to make it fit the widened lower. You have to use a 5.4 specific timing cover but you must weld on tabs or make brackets to hold the secondary belt drive for the supercharger. The alt brackets must be changed as well and you have to mod the timing cover for the alt brackets to mount to it. Your exhaust location will end up moving up and outward alittle due to the taller deck height. Wiring harness as to be extended in certain places to make it fit(This is depending on a few other things though) You will have to mix and match various parts in order to make it work but it has been done before a few times.

Ask me how I know all of this....??? :thumbsup:

I think you've just talked me out of this consideration lol. Thanks for the info though.

Adding to what Ironhand said. A 2V 5.4L is an easy swap into a mustang. a 4V is not. CrazyDave or something like that makes everything you need to drop your 5.4L 4V into a mustang. To do a 2V you need intake adapters or new intake and headers and you are good to go.

This is great information. My buddy with the 2v is going to like this. I'm assuming the 2v would need a 5.4 timing cover also? I'm trying to find more info on a 2v swap to see if my friend and I want to tackle this project with his car.

I don't think it would be worth it to do it with my 4v s/c setup.

Godstang..do you know everything about these cars? You post on everything lol i bow to you cobragod

He's one of the most knowledgable people I know of when it comes to the 03/04 Cobras

Aaron, looking at your current mods (in your signature), I take it you're just not satisfied with your present setup? Just curious because what you've got is pretty impressive.

Well, my motor is down (spun bearing) and my friends 2v is down also. He was thinking about swapping to a 5.4 and just use everything he has now. Then I started thinking about the possibility of a 5.4 in mine. I don't think I'll be doing a 5.4 in mine now that I have some good info on it. However, the 2v 5.4 sounds like it might be worth it.

 

[97desertCobra]

Not exactly true. A boss block un-machined is 1K. Plus rods and pistons alone is right at another 1200-1400, plus the cost of a crank, rod and main bearing etc... Considering I have less money tied up in my complete Shelby shortblock then the cost of your block, rods and pistons. You would be incorrect in your assumption.

Your idea is the easiest of the two, kinda, but I guess it depends on who you are really. To me this is easy only because I like to figure stuff out. There are pros and cons to every build. But if I wanted to I could do the same thing and bore and stroke the 5.4 and come out with 388 cubic inches and your long rod, big bore 324 wouldnt be as tough as the stroked 5.4. Also look at the valley on the 5.4 block, it is pretty beefy and perfer it over the 4.6 blocks due to rigidity.

Did you buy this Shelby short block new or used? I'm sure that has a big effect on the price. New vs new the cost will be closer, and with the Boss block you don't have to even anywhere near the amount of modification and fabrication to get the timing cover, heads and intake to bolt up. Also with the ability to run the 03-04 Cobra intake you are open to all different kinds of blower set ups. From the larger PD's to even the centris and turbos. Just source a 01 Cobra intake or a sullivan and you can run a nice centri or trubo set up. You can also get a sullivan intake for 5.4's, MMR makes one also, but they are much more pricey than the 4.6 versions. There is just more out there option wise for the 4.6. FR500, 01 Cobra, 03 Mach 1, FR500C, Sullivan etc. As for the rigitidy of the 4.6, I'm talking about the Boss big bore iron block, not sleaving a 4.6! The Boss block is stout!

As for the 388 ci modular, I don't see that being very strong either, especially if we are talking about forced induction. But if we are talking n/a then :bowdown: