Well you guys might think im crazy but I have a good Idea for a really good really HIGH hp 5.4 L. You see I dont have a truck, i have a 4.6L SOHC mustang GT and this hole little 281cc is not working for me so i found out that some one had put a 5.4L Triton motor in there mustang and it sounded like a good idea. Well i had a few questions about the motor and i bet you guys are the best people to ask. I know that all 5.4L come with a steal crank and a stoke something like 4.162. Well thats as big as a chevy 427! And I know that Ford Racing put the 5.4L in the Cobra R and that makes 398hp and 398t. But Im thinking that the 5.4L could do lots more then that. What year did F-150 start coming out with the Triton V8? What is the differince in a F-150 and F-250s motor? is it just the cams? I was wonding if 5.4L has 4 bolt or 2 bolt mains? Also can it be bored out any? Does anyone know if the 4.6/5.4 are the same block with a differint stroke and bore or are they compleatly differint? Now i know you can put DOHC on the GT block and you can put SOHC on the Cobra block thats why i ask if the 4.6 and 5.4 are the same. And does anyone know with the DOHC form a Cobra bolt onto the 5.4L. The way I look at it if you could take a 5.4L, put the cobra heads on it along with some big nasty cams and all the other little goodies that races car gets (80mm mass air, 75mm tb, 36lp. injectors) you could get one hell of a motor. And with that big of a stroke and a steal crank if the 5.4L has 4 bolt mains then not only would you have a great motor you could also give it a good 200+hp shot of nos. So if anyone knows the answer plese post it or e-mail me at dangermony(No Email Addresses In Posts!)

thanks

 

4.6's and 5.4's are same design with the 5.4 having a taller deck height. Sort of like comparing a 302 to a 351. The DOHC heads from a Cobra will fit on a 5.4 L. You need the front covers off of a 5.4L DOHC Lincoln Navigator motor, as well as the timing chains. The hardest thing to come by is a good intake for hp on this engine. The only intakes available are the Lincoln intake which is no good for hp or the Cobra R intake which supposedely only fits Cobra R heads. They are beaucoup bucks. The bore of the 5.4 is the same as the 4.6. The 5.4 gets it's extra cubes from stroke only. I did read a story about a guy that did the same thing in a racing Mustang. He built an all out 5.4 DOHC. It had a stock crank, stock rods, and stock heads and this guy was making over 1200 hp. Of course he had a gigantic SC that was pumping like 25 psi, too. Still, a properly tuned DOHC 5.4 with good cams should be able to make 400-450 hp and still be streetable. If you are talking about forced induction or NOS then the hp number is through the roof. One place you might check is Sean Hyland Motorsports. I know they have done this type of thing and used to sell 5.4DOHC crate motors. I heard he's a little cocky, but he is good.

JJ

 

i just got through swapping a 32V 5.4L Navigator Engine into a 97 4.6L 2V. I agree with bigsnag, the intake is certainly not designed for big horsepower and would need to be custom.

 

I've had a simalar idea in the past. So If I got a hold of a 5.4 shortblock, I can use modular heads of my choice and whatever intake manifold works w/ the heads? Also what is the difference between the navigator heads and the cobra heads just cams?

 

just throwing this out there could he not find a ford gt intake and also why Frankenstein everything together when you could just pull a dohc 5.4 out of a Lincoln blackwood I've read that 5.4 is the same one they put in the ford gt so couldn't you grab one of those and use ford gt bolt ons like the intake and headers? Legit asking i dont know the dohc motors very well however 5 mustangs and 7 f150s later i can tell you stay away from an 04 up triton period lol i put an 02 5.4 in my 06 gt just to avoid epic failure of my valve train lol worked nicely too new cams headers and intake and a port and polish and 04 cobras couldnt catch me and i had a motor good for 300k with no issues and no forced induction i was 399 to the wheels after tune

 

Those guys were talking about 5.4 stuff 18 years and 4 months ago. They probably moved on to an LS and never looked back.

 

There's always one or more reasons why a thread just dies off---this one maybe because there's just no interest in such a project or question?