I have an 02 5.4l that im going to be rebuilding in the next year. So i figured i start putting together the parts im going to want.

Id like to build the engine to make power gains every where. I use the truck to play in on the highway/offroad, and i tow 7500lb race trailer on the weekend.


Currently im running my sig rig and it does good.

02 5.4l Triton
CAI
OBX long tube header, no cats, flow master 50 series duals
Gryphon custom programs.

My goal is to swap navigator 4v heads and intake over to my engine when i rebuild it. Also to bore the motor our as far as it will go and raise the compression to around 10:1. I think the intech 5.4l made 340hp when the 2v make 260. Not sure what the torque was for the 4v.

So questions.

What years of intech heads will work/be most benificial.

Are the manifolds on the 4v heads the same as the stock PI heads?

What pistons should i look at?

How far can the mod block be bored? .060?

Any other suggestions?

Dont say S/C . I have always wanted to do one, but doing that will still require me to build the engine as im sure it wont take boost for ever with the miles that are on it already. Although im sure it would run much longer.

Thanks

 

4V Navigator 5.4L's made 300hp/355ft-lbs
All of the 4V 5.4L heads used on Navigators/Blackwoods are the same as far as power output.
No, the Exhaust manifolds are different.They are in the same location dimensionally as the 2V, so your current exhaust will only need slight mods to work.
IMO-you need a set of aftermarket flat-top pistons that put the piston's crown up at the top of the bore for more compression. The OE pistons are recessed in the bore around .120".
.040" over is about the max you can go for boresize unless you sleeve the block and do a "big bore" kit"
Get some good I-beam rods so you can rev the engine a bit higher. One of the problems with the 5.4L 4V is that it's still making good power when it hit the RPM that the rods start to get "iffy". Those Navi heads DO NOT need any enlargement of the ports, they're already HUGE in comparison to the other 4V's. Portwork is beneficial, but it MUST be done by someone that understands the heads, and how to increase flow by radius and throat work, and not just making the ports larger. Get good bearings, Clevite or FM tri-metals. The OE aluminum bearings are good, but they are not forgiving to any debris that gets into the system and past the filters.
JL

 

As always Johnny, awsome reply.

Thank you.

I dont think i would want to sleeve the motor. .040 should be enough. Displacement will be around 337 ci.

Im estimating my current setup around 300 hp.

Im hoping with this new build to make 380hp at the crank. and maybe north of 400 ft lb. Truck will still be a toy/hauler.

Id love to spin the motor farther as well. but the OEM Tq converter is only good for 5200 rpm before it starts to ballon.


Any suggestions on a good converter that will work for towing.

 

380 at the crank..Not with a stock Truck/Navi intake.Sorry, just ain't gonna happen. You might get close, but I doubt you'll get to 380 with it.
As for a converter-Call Chris at Circle D Specialties in Houston. he'll get you what you need for a fair price. There is cheaper out there, but that's exactly what it is..CHEAPer.
JL

 

Is there a better Intake?

 

For Navi heads, none that I know of that'll still work for what your intended use of the truck. Well, there is the Cobra "R" intake, but that thing is made of "unobtanium", and they're nearly impossible to acquire.
In all honesty-350rwhp is ALOT. Even in a truck, that's ALOT of power. I'd be really surprised if your current 5.4L 2V (even with the mods you have done) is making more than 280-285 fwhp. The CAI is really worth nothing, the headers and exhaust are worth a bit at certain points of the powerband, but peak will not gain more than 10-15 hp at the most with stock heads, and the tunes are only as good as the guy configuring the software. The difference in driving the identical same vehicles (Expy vs Navi) with a 5.4L 2V and a 5.4L 4V is night and day, and there's only a 40 fwhp difference between to two.
JL

 

Any suggestions?

 

Don't have unrealistic expectation based on mythical numbers.
IMO- a 5.4L 4V is an excellent powerplant, and if built with 10.5-11:1CR pistons and a good set of rods, it'll make very good power/torque with a slightly extended RPM range over stock. Using stock intake or exhaust cams from other 4V engines can help tailor the powerband to be more inline with what one would use the truck for in a DD/towing application, yet still make good power and be reliable.
JL

 

If i ran the 10.5-11.1 i would assume id need to run on premium 91 octane at least right.

I have no problem with that now at all, i usually run it anyways, but when fuel goes back to $4 a gallon, which it might. I dont want to be stuck at that, it would be nice to be able to drop back to 89 e10 for cheapness.

 

The Navigator Intech was designed for a minimum of 91 octane anyway. People get FAR too hung up on premium fuel being more expensive.Think about it. It's about .25/gal more than regular unleaded. If your truck has the 25 gallon tank, if it was BONE DRY that's only $6.25 more per fill up. If you can't afford $6.25 more per fill up, then you can't afford an engine swap/build-Seriously.
You could tune the engine for regular unleaded by altering the spark tables, but the costs for building a proper spark table on the dyno for regular unleaded is gonna be around $350. It would take around 1400 gallons of fuel (or 21K miles of driving at 15 mpg) to recover that investment.
JL

 

Excellent info!

burnstoughford....just curious...with willingness to to go through all that trouble to do this to your unit/engine...why not get a engine from a salvage yard (out of a navigator), and build it /overhaul it to what you want and then have it ready to go...rather than adding it to your current block/engine seems that would save a-lot of down time of your truck? Maybe that is the direction you're headed.

Would swapping out the 5.4 2v for the 5.4 4v and all the "upgrades" (cam, bore job, heads, etc) as described ,basically a tweeked Navigator engine, require the ECM of the Navigator??

I was thinking that on the Speed channel, sometime ago,....Power block, or Trucks...er' one of those shows they highlighted a show on a rebuild of a 5.4 N/A and got all kinds of power,
doing probably much of what was suggested, IF memory serves... somewhere in the neighborhood of 480hp?? what the end application was IDK...mustang, racer, truck??

anything is possible I suppose with enough $$$

 

Because i want to have an entire new bottom end basically. And i want to go through my engine myself. And i want to bump compression. Who knows i might end up buying a navigator motor in the process of trying to get heads. Time will tell. Im just trying to get the facts on what components to line up right now.

Thanks for the input though.

 

No. The 2V PCM can be custom programmed to work perfectly.
Not with a Navigator intake manifold.
JL

 

What one did they use? I know the Cobra one is non exhistant. I think there was only 300 of those cars made. Thats why i was wondering if there was an alternative. Obvious thing is that i wouldnt want peak hp as much as broad hp/tq bands. Hard to tell what there intake setup would a produced for usable power.

 

Sounds like a fun project. But I wouldn't go .040 over!
Most guys only go 0.20 and 0.30 is pushing the limit.