Headers on a 2000 F150 4.6 V8?
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The Gibson stainless ones.
+1 the Gibson Shorty stainless, not need to raise the cab on this one but the manifolds can be a PITA to remove, be prepared for broken studs.
Install them with new Ford stainless studs and nuts or copper aftermarket nuts.
Originally Posted By: Trav
+1 the Gibson Shorty stainless, not need to raise the cab on this one but the manifolds can be a PITA to remove, be prepared for broken studs.
Install them with new Ford stainless studs and nuts or copper aftermarket nuts.
So your saying headers won't help at all in regards to performance,gas mileage ect?
Then what are a list of inexpensive things I can do that will be worth spending the money on?
Originally Posted By: Linctex
NONE.
That engine is "Non-PI" and headers really don't do anything for it.
The PI Intake/heads went on the Romeo 4.6 (NOT Windsor) in 2001
From this post:
https://www.ford-trucks.com/forums/852198-can-you-upgrade-a-4-6-npi-to-pi.html
The heads,etc from a car are interchangeable with a truck/van, but using the car intake will make the truck/van a gutless pig. Dimensionally, all Modulars are the same. There are small quirky differences between Windsor and Romeo versions of the engines that'll drive you nuts trying to finish up a swap like your speaking of. Bolt sizes,timing cover differences,etc,etc.
The 60rwhp number is bogus.
By swapping the heads,cams,etc all out from that of a E150 or F150 with PI heads will get you 20-25rwhp. You've gotta remember,many of the people discussing the PI swap are talking about doing it on Mustangs that have a MUCH better flowing intake manifold,and they're usually swapping on a set of ported heads with aftermarket camshafts.
'98 NPI truck engines were rated 220hp,and the '01-up PI head truck engines are rated 240hp.
The cylinder heads themselves are honestly equals when it comes to capability of airflow-the camshafts, intake manifold, and the PCM tune are where all of the power gains come from.
There a minimal amount of power to be gained in a truck PI intake - it's still got the same restrictive design for low-end torque production as it's NPI counterpart-just ever so slightly less, and it's port shape is for the more squarish PI intake ports so it'll seal to the cylinder head properly.
As for parts sourcing based on years:
'97-'99 are the same
'00-present are all the same
This is based on the cylinder head type and camshaft specs. There are little differences through the years,but as far as power potential-the above is true.
I've driven both PI head and NPI head trucks- the '01 F150 work truck with PI heads (supercab 4.6L/4R70W 2WD) compared to my old '98 F150 with NPI heads and PI cams (supercab 4.6L/4R70W 2WD),and it was almost impossible to tell the difference between the two.
I would'nt touch the heads-I'd swap the cams and be done. There's not enough power gain benefit to offset the absurd amount of work to pull the heads,etc and the costs involved with head gaskets and head bolts,etc.
Originally Posted By: lawnguy
Then what are a list of inexpensive things I can do that will be worth spending the money on?
Which exact cam would you put in,and replace the factory oem cam? What differences will I notice both positive and negative?
Originally Posted By: Linctex
From this post:
https://www.ford-trucks.com/forums/852198-can-you-upgrade-a-4-6-npi-to-pi.html
The heads,etc from a car are interchangeable with a truck/van, but using the car intake will make the truck/van a gutless pig. Dimensionally, all Modulars are the same. There are small quirky differences between Windsor and Romeo versions of the engines that'll drive you nuts trying to finish up a swap like your speaking of. Bolt sizes,timing cover differences,etc,etc.
The 60rwhp number is bogus.
By swapping the heads,cams,etc all out from that of a E150 or F150 with PI heads will get you 20-25rwhp. You've gotta remember,many of the people discussing the PI swap are talking about doing it on Mustangs that have a MUCH better flowing intake manifold,and they're usually swapping on a set of ported heads with aftermarket camshafts.
'98 NPI truck engines were rated 220hp,and the '01-up PI head truck engines are rated 240hp.
The cylinder heads themselves are honestly equals when it comes to capability of airflow-the camshafts, intake manifold, and the PCM tune are where all of the power gains come from.
There a minimal amount of power to be gained in a truck PI intake - it's still got the same restrictive design for low-end torque production as it's NPI counterpart-just ever so slightly less, and it's port shape is for the more squarish PI intake ports so it'll seal to the cylinder head properly.
As for parts sourcing based on years:
'97-'99 are the same
'00-present are all the same
This is based on the cylinder head type and camshaft specs. There are little differences through the years,but as far as power potential-the above is true.
I've driven both PI head and NPI head trucks- the '01 F150 work truck with PI heads (supercab 4.6L/4R70W 2WD) compared to my old '98 F150 with NPI heads and PI cams (supercab 4.6L/4R70W 2WD),and it was almost impossible to tell the difference between the two.
I would'nt touch the heads-I'd swap the cams and be done. There's not enough power gain benefit to offset the absurd amount of work to pull the heads,etc and the costs involved with head gaskets and head bolts,etc.
If the studs are broken and the manifolds are leaking you can buy replacement Dorman manifolds for like $50 each. Spend $150 on two manifolds and stainless studs. If you have no leaks id leave it alone.
Modern computer-controlled emissions equipped engines *with a catalytic converter* don't benefit from legal CARB-complliant headers.
"Shorty" headers are just manifolds anyway. A header manufacturer can't get a CARB number for a true header for an ODBII engine. AT the same time, the OEMs these days build manifolds that flow quite well, probably capable of handling 10 or more % more flow than the stock motor needs. And they're quiet.
The shorty's look cool, but be sure you understand that's why they're in the market. They may rob torque from your truck motor which is not ideal.
Remember the no 1 rule of exhaust enhancements: they must be made in coordination with compatible intake flow improvements. If you're not touching the rest of the motor, they are almost guaranteed to do nothing (if you're lucky) or cost some power (if you're not).
No benefit except looks. Potential for more leaks and loose hardware in the future. Harley / Lightning used the same exhaust manifolds as non boosted so that says something. I have had an 01 f-150 5.4l for a long time and toyed with the idea of shorty headers. The Cat. Converters make some odd noises already so I just left it alone. Don't want to make a new problem. Ford of course says it's normal to sound like [censored] and offer some exhaust shield wrap kit for $600.
I did the stainless headers on my 98 4.6L F150 (which now has something like 380,000 miles on it) I also added a Gibson single sweptside exhaust a superchips "chip" , K+N and larger airbox intake tube.
It made very little difference. A couple of things, the headers themselves sound "tinny" as a little noise escapes through the walls of the thin header tubing (not a leak) . I ended up putting tons of insulation on the footwells to quiet down the additional crummy noise. The cast iron manifolds do a good job keeping the engine quiet.
I will tell you that the PI Police interceptor 4.6L is a far more powerful engine, mostly due to it's high revving nature, than my truck engine is.
Also, when the Gibson exhaust finally rusted, I put back on the stock exhaust. It lost some high RPM "umph" for sure.
If I were to guess, I'd say all the mods added 10HP.
OK, power 101 - it all comes from fuel. To make more power, you have to burn more fuel. When someone says these heads flow better, that is what they do - flow more air. But if you keep the stoichiometric ratio where it needs to be, you will have to increase fuel flow. That is why OEM sell bigger engines when customers want more power. Physically bigger engine, or better flowing system on existing engine and wind it tighter - only two ways t get more power.
And none of this means much below 3,500 RPM where the OEMs have really done their homework. If they could get 5 hp w/o hitting the fuel consumption numbers, they'd be all over it. They'd spend millions to get it fleet wide. HP sells cars. Headers may actually hurt below 3,500 unless temp tape wrapped. Iron manifolds retain the heat to help keep exhaust flow high at low engine speeds ...
So if you are living above 3,500 much - it might help a little ... If you drive mostly below that - not going to help.
An increase in dynamic compression ratio will give you more torque and means more felt power. But if you are already living on the anti-knock sensor pulling timing, you can't do much about adding CR either ...
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Shorty headers are factory equipment on my 6.1. They are elaborately enclosed in a shell for sound absorption and underhood heat control.
Fitting headers on any modern engine is almost a waste without specific tuning to take advantage of them. Many folks simply move the torque further up the rev range thus actually making the car a bit slower in a sprint which may not be what you want...
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Originally Posted By: lawnguy
Another gentleman on here recommended a different cam. Can ya'll talk about that in regards to the negatives and the positives to a different cam.
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