4.6 4V Question

flstang65

10 Year Member
Dec 6, 2007
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SE Georgia
I found a deal on a 4.6 4V out on Lincoln Aviator. Other than the cams, what else should I be aware of, and is it worth the work? I know they come with about 302-305 hp and I am going to freshen it up a bit and throw some parts on it to make it worth my while. That is, if it is even worth the hassle. Thanks :SNSign:.
 
Yeah, love the Navigator motor, great heads and should be a great project.

Hope this writeup on their 4v heads helps.

http://www.modmotortech.com/forums/showthread.php?t=295 said:
Navigator: (98+ Lincoln Navigator)
These 5.4L DOHC heads feature essentially the same intake port design as C heads, however they have a much larger intake port volume than 4.6L castings. Despite the fact these heads feature a relatively small exhaust port, the extra intake port volume could be very beneficial in helping fill a motor of greater displacement—think 5.4L. Expect slightly better midrange torque, and sub 8000rpm horsepower production than even C heads, however the larger intake port size leaves a slim selection of intakes to choose from when utilized on a 4.6L block. Forced induction fans take note, Navigator exhaust ports feature a thicker exhaust divider (while keeping the same overall exhaust port size as B,C, and FR500 heads) that allows coolant to circulate through this vital area. Conversely however, the larger divider can also hurt flow by utilizing additional space in the port.
The real downside to Navigator heads, when used on a 4.6L based motor, is the severe limitation they impose on intake selection. The physically larger 5.4L heads don’t leave a lot of room (when installed on a 4.6L block) between them for an intake plenum to sit—though they do bolt right up. Remember that since Navigator intake ports are essentially clones of those of C heads (just on a larger scale), they too suffer from the same intake port flaws that plague the earlier tumble port design--no short turn or floor in the throat of the intake port.

The Bottom Line: The extra port volume the Navi’s possess could be very beneficial in filling a motor with greater than 281 cubic inches of displacement, or in high rpm N/A street/strip or boosted combinations. Fans of boost should remember the cooled exhaust port divider. Lack of intake availability is the real downfall of this otherwise wonderful casting.

Stock Intake Choices: None (4.6L), 98+ Navigator (5.4L)
Aftermarket/Modified Stock Intake Choices: Al Papitto short runner 99 Cobra (4.6L), sheet metal
Navigator head dimensions: Combustion Chamber: 53cc, Intake Port Vol.: 184cc, Intake Port Entrance: 2.290”x1.400”, Valves: 37mm Int., 30mm Exh.
 
Yeah, love the Navigator motor, great heads and should be a great project.

Hope this writeup on their 4v heads helps.
Its the Aviator not the Nav. :shrug:
Its the 4.6 version and yeah its more like a Mach motor with the 6 bolt crank. Definatly worth it. I assume this is for the 04? If so you can use the computer you have and just reflash it for the engine. For your car it will be a pretty easy drop in. IDK if the block is aluminum though. I doubt it, prolly the iron block :shrug:
 
EDIT: Okay, its the aluminum block and the aluminum "C" heads with a 6 bolt crank and 6 bolt main bearings. It does have the IMRCs which you will want to delete because you dont have the controlls for it (you will only loose 10lbs of torque below 3200rpm) but wont hurt high rpm power at all.
Also the plenum is way to large to fit under the hood so you will eaither need a BIG cowl (4"+) or a 99/01 Cobra plenum or (my personal choice) find an Eaton and lower plenum from an 03/04 Termi. You can get them for under $800 and with that engine you will have 440+ flywheel hp running stock boost levels :nice:

Aviator’s engine delivers peak power of 302 horsepower at 5,750 rpm and peak torque of 300 lbs.-ft. at 3,250 rpm; 90 percent of peak torque is available at only 2,000 rpm. It meets the California Air Resources Board’s Ultra Low Emission Vehicle (ULEV) standard.

The Aviator team began with a new, very rigid aluminum block that weighs 70 pounds less than a comparable iron block. It is fitted it with 10.03:1 high-compression pistons for good power and fuel economy, and upgraded connecting rods for durability. New aluminum four-valve heads and an aluminum intake manifold with variable-length runners optimize airflow at all engine speeds to improve low-speed tractability and high-rpm power with greatly reduced combustion noise.


LOW RPM
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HIGH RPM
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Often, engine designers use aggressive intake port tuning for a high degree of tumble in the intake charge to achieve quick and powerful combustion for good torque at low engine speeds. Two disadvantages of this approach are increased noise at high engine speeds and reduced peak power. But Aviator uses an internal valve to switch from a long intake path at low engine speeds to a short intake path at high speeds. The long path produces a column of air that helps promote better cylinder filling for more torque and better low-end response than a traditional intake. When the manifold switches to the short-path configuration, the engine breathes more freely to maximize peak power.

Aviator engineers took other actions to reduce the engines sound levels during development. For example, the rigid deep-skirt block has six-bolt main bearing caps and a lower architecture that limits bolt forces to the vertical direction, which improves overall stiffness and reduces noise. New computer-engineered engine mounts not only lessen the transmission of noise and vibration to the chassis but also are tuned to use the engine as a mass damper for better ride comfort.

Other noise-fighting features include very stiff accessory mounts, roller-finger cam followers, dual fuel rail dampers and a thicker front engine cover. A molded engine shroud further reduces sound levels, but Aviator engine design engineer Rob McWilliams notes, “We found that by carefully studying noise sources and making subtle changes, we could deliver impressive refinement throughout the power band without having to resort to aggressive sound-blanketing techniques.”
 

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Its the Aviator not the Nav. :shrug:
Its the 4.6 version and yeah its more like a Mach motor with the 6 bolt crank. Definatly worth it. I assume this is for the 04? If so you can use the computer you have and just reflash it for the engine. For your car it will be a pretty easy drop in. IDK if the block is aluminum though. I doubt it, prolly the iron block :shrug:

Looks like somebody here needs glasses. :(
 
thanks guys!. looks like i am going to do it. it may have to sit a little but its a good deal and ill have time to save up to get the parts i need. and yes its for the 04. ill just stick the original motor on a stand and save it. I should be able to use my sniper to re flash the computer? and the exhaust ports should be the same as on a cobra, so i can get me some long turbes to go in it since ill have the engine out. Lastly, My 3650 tranny should bolt up?
 
I'm trying to work a deal with the guy. If I can get it, I am going to do a budget build. Not a whole lot of cash laying around since my girl and I are having to pay for most of our wedding. So, engine included, I am going to try and do this all on the cheap. Engine, stock cobra cams, longtubes, and a good used 03-04 Termi blower set up with a pulley and throttle body.

How difficult would it be to port the termi blower?
 
IDK what site it was. I was searching for "Aviator engine" pics and it came up :shrug:

As far as the porting you may wana hit up hotmustang331 as he ported his himself :nice:
 
IDK what site it was. I was searching for "Aviator engine" pics and it came up :shrug:

As far as the porting you may wana hit up hotmustang331 as he ported his himself :nice:

and i followed him in process, he has done some more on his b/c he got a wide oval tb. Whenever i get a few more buck to have the pulley installed and buy another serpentine i'll have a "spare" m112 here. will be a good time too, right at 50k miles...:nice:
 
hold on one second.


1st, the aviator intake is considered to be the BEST PART TO MOD FOR POWER. PERIOD. keep the imrc's and activate them with an MSD rpmswitch. that simple. low end ANd 6500 when prepped.

if it's an 04-05 aviator it has the best heads ever put on a regular production ford. they rival the fr500 part. look into it.


you will find the aviator modded will make as much torque as most 5.4's modded. i am talking 345rwtq range.

it will handle N/A revv's as well as 8 bolt steel. the limit being the rods not the crank.


you simply cannot boost it much with the high compression ratio. without forgings.
 
well IMO its like boosting a 10.4:1 2v. how much do you want on a stock block. sometimes they do well, but from my reading it's meth injected guys with good blowers. the m112 cannot be classified as a good blower. a lot of heat generated, and if you coolant temps rise enough where intercooling suffers....

you are dealing with pistons 30% stronger than cast but will shatter. and rods that are pressed metal.


i would think 8psi should be safe if cool. but dude....


all motor that engine can deliver cammed power in excess of 350rwhp. easily. and bolt-on power in the 325rwhp range. WITH torque.
 
Well, after talking to you guys and doing a ton of research on my own, I have finally come to a conclusion. I think I am going to pass on the engine. For a couple reasons. The potential problems with adding boost on this engine, aluminum block, the rods, and a few others. I am just going to wait around for a wrecked Mach 1 or Cobra to show up and snag the motor out of it. In the mean time, I am going to stick to my original plan and build the suspension. No sense in having the power if you can't put it down. Thanks for all your help guys.