New 5.4L DOHC Intake for Navi heads - Pics Inside!

sounds really interesting....I will ditch the AC :)...
I guess I will need to get some forged internals for the 5.4L too...I
was gonna go with a 5.3L stroker/bored kit /KB blower for my 4.6 but I think I will go with that 5.4L dohc. Will I need a full cobra exhaust system or only headers ?...also in the mean time when waiting for the KB blower + intake from modular perf..is there a way to fit a 4.6 intake o ntop of the block ?..thanks
 
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I'm confused...i thought the 03 cobra DOHC heads are generally identical to that of the dohc heads on the 5.4L. I guess they are not? What is the benefit of using the navigator heads over 03 cobra heads? I guess price would be the main thing. Where is the best place to get a block w/ heads (01 navigator?) I also would liek to hear what they sound like with flowmasters...if they sound as good as the 4.6L then that'll work...but if they sound like the 4.6L/5.4L truck engines does ughhh.

kirkyg
 
lmao...
for some reason there top picture doesn't show up i guess the link is wrong. Not bad $3700...i just need to start figuring up how much all the little extras will cost. How much hp does these motors usually put out in their stock trim? And then how much to expect with the new intake with long runners (setup for a KB blower)?

If i go 5.4L route i'll build the engine to be ready to push massive boost and then get the blower after the engine is completely done (p&p, cams etc.)

What about wiring harness? Can all this be adapted or what?

kirkyg
 
kirkyg said:
I'm confused...i thought the 03 cobra DOHC heads are generally identical to that of the dohc heads on the 5.4L. I guess they are not? What is the benefit of using the navigator heads over 03 cobra heads? I guess price would be the main thing. Where is the best place to get a block w/ heads (01 navigator?) I also would liek to hear what they sound like with flowmasters...if they sound as good as the 4.6L then that'll work...but if they sound like the 4.6L/5.4L truck engines does ughhh.

kirkyg

The 5.4L Navigator heads are just like the 99-up 4.6L DOHC tumble port heads, EXCEPT they have larger intake ports. The extra port volume is needed to feed the extra 50cid.

Al Papitto / Boss 330 runs navi heads on his 5.4L DOHC n/a to 500rwhp and 10.40's.
 
DOHC330Mustang said:
The 5.4L Navigator heads are just like the 99-up 4.6L DOHC tumble port heads, EXCEPT they have larger intake ports. The extra port volume is needed to feed the extra 50cid.

Al Papitto / Boss 330 runs navi heads on his 5.4L DOHC n/a to 500rwhp and 10.40's.

wow now thats impressive. I can't imagine the power of that + a twin screw supercharger : :eek: :jaw:

kirkyg
 
kirkyg said:
Yea sometime in 2001 they switched over...how would you be able to tell if you got a forged crank or not?

kirkyg

One way is casting / PN#'s, do a search on the corral, the info is there.

Al Papitto's wife had this info on the Corral...

Part numbers aren't usually on the cranks, a forging # for a steel 5.4 crank is F75E or F75AE and at a glance the steel cranks have a dark blue/purple color due to induction hardening.
Cast cranks have a dull gray color.
 
My other concern now is not about internals its about the computer. I'm quite sure how the 5.4L with navigator heads will work with the GT wiring harness and computer? Will i need a cobras wiring harness or just a dyno tune on the GT setup to get this to work?

kirkyg
 
kirkyg said:
My other concern now is not about internals its about the PSM. I'm quite sure how the 5.4L with navigator heads will work with the GT wiring harness and PSM? Will i need a cobras wiring harness or just a dyno tune on the GT psm to get this to work?

kirkyg

You can modify your GT harness and chip tune the GT ECU, or you can swap in a Cobra wiring harness and chip tune the ECU.
 
Is the cobra wiring harness possible too? Or is it too much trouble to mess with. The reason i ask is because i've always wanted a gauge cluster with a higher mph on it. And if i could get the cluster with for a cobra then i could go that route. It may just be not worth the trouble though.

kirkyg
 
kirkyg said:
Is the cobra wiring harness possible too? Or is it too much trouble to mess with. The reason i ask is because i've always wanted a gauge cluster with a higher mph on it. And if i could get the cluster with for a cobra then i could go that route. It may just be not worth the trouble though.

kirkyg

Cobra harness for the DOHC swap wouldn't be too much, but to change the Speedo, you'd need to get into the harness that runs into the dash. Not sure how difficult that is because I've never done it. Do a search on the corral on wiring harness SOHC to DOHC and see what comes up.