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5.4L dohc in 86 GT. Which headers??

ModFoxMustangs

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Staff member
I'm looking forward to seeing it come together. I have started acquiring the parts to do the MSD set up as well, but so far all I've picked up is the four ignition adapter modules. I will get the rest as funding permits.
Do you all have pics of the MSD setup or info?
 

Bill

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Staff member
Donator
The part numbers for the 99 Cobra are MSD 62152 (2 required), MSD 82448 (set of 8 coil on plug), MSD 88813 (wiring harnes, 2 required), MSD 89121 (4 required). MSD has installation instructions available for each of these. I will try to get them posted.
 

na svt

Member
The difference in power between the stock manifolds and any of the shorty offereings is minimal. If you're able to pick up shortys cheaply they may be worth it, but paying full price for a set of undersized (expecially for a 5.4) JBAs is not a good bang for the buck purchase.

As far as long tubes go, a 5.4 needs at least 1.75" primarys. Even 4.6s make more power with them when compared to the 1.625" headers.

MSD MOD6 http://www.msdignition.com/uploadedFiles/MSDIgnitioncom/Products/RPM_Timing_Controls/6011_instructions.pdf
MSD 62152 http://www.msdignition.com/instructions/Products/Ignitions/62152.pdf?terms=62152
COPs (not recommended) http://www.msdignition.com/instructions/Products/82448.pdf?terms=82448
88813 harness http://www.msdignition.com/uploadedFiles/MSDIgnitioncom/Products/Accessories/88813_instructions.pdf
COP adapter http://www.msdignition.com/uploadedFiles/MSDIgnitioncom/Products/Accessories/89121_instructions.pdf

I recommend these over the MSD COPs as these are far more reliable: http://www.cjponyparts.com/ford-racing-ignition-coil-set-stock-5-4l-gt500-2007-2012/p/M120294V/
 

Bill

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Staff member
Donator
I would have to disagree. There are a number of reason to use the better quality headers. For the novice builder it makes the build easier. In terms of performance, the headers are simply part of the system and will make increasingly more power as the system becomes more than the sum of its parts. The JBA Firecone headers work as a scavenge system, directing the flow of the exhaust instead of simply providing a vent outlet. The coating focuses the heat into the mid-pipe section and away from the bay. This provides a number of additional benifits, including making high flow cats work better and protecting sensitive compontents from unwanted heat exposure. I don't recommend the big long-tubes for a street driven car. They do make more HP on a dyno, but you rarely have the conditions to take advantage of them under street driving conditions. There are a number of other draw backs in terms of installation and maintenance issues as well. Sometimes it boils down to budget. In that case, I guess all this really doesn't matter.
 

na svt

Member
Longtubes increase tq and midrange hp by a great amount. Therefore you don't have to spin the engine high to take advantage of the gains offered by them.

The Jba "firecone" is a joke, those shortys add about 3rwhp over stock manifolds.
 

Svt Fox

Well-Known Member
Staff member
Longtubes increase tq and midrange hp by a great amount. Therefore you don't have to spin the engine high to take advantage if the gains offered by them.

The Jba "firecone" is a joke, those shortys add about 3rwhp over stock manifolds.
Correct me if I'm wrong but 5.4's (stock) don't like to live over 7k do they? IIRC, don't they have an oil starvation issue in the oil pan, in the higher rpm range?
 

Bill

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Staff member
Donator
How often do you really take a 5.4 above 7k for a sustained pull? The typical Triton doesn't have cams to take advantage of the higher RPMs. If you're in a drag only configuration, you generally only hit that level for 0.3 to 0.7 seconds unless you have a 2-speed tranny. If your doing autocross or open track, the 5.4 conversion is probably not the best choice due to weight imbalace. Street driving is going to put the power band somewhere between 2000 and 5800 depending on all the parts chosen and the tune. The 5.4 in my 150 likes 2400 to 4200 best, but it has an automatic tranny. As for short vs. long, brands and scavenging, that's a really long discussion. We've had great luck with the firecone shorts and mids. We sold and installed a lot of headers over the years (short, mids and longs) from multiple manufacturers. Our dyno tech was always able to get more than 3rwhp out of the JBAs. Of course it is just one link in a long airflow system. Its all good. There is a niche in the market for just about everything.
 

Svt Fox

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Staff member
If your doing autocross or open track, the 5.4 conversion is probably not the best choice due to weight imbalace.
If that's true, why did Ford put it in the 00R or any of the cars (take your pick) that came with an N/A 5.4 in Australia?
 

na svt

Member
Whos talking about 7000. Longtubes add a lot of ta and midrange hp, 3k-5k. I've added headers to many mod motors everyone had good midrange gains; right where you need it most.

I've never seen a impressive amount of power come out of a cimbo that had shortys of any type.
 

Bill

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Staff member
Donator
If that's true, why did Ford put it in the 00R or any of the cars (take your pick) that came with an N/A 5.4 in Australia?
We're talking Fox conversion, not factory a engineered chassis. It will work, and could be countered to balance out pretty well. Just takes money
 

Svt Fox

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Staff member
We're talking Fox conversion, not factory a engineered chassis. It will work, and could be countered to balance out pretty well. Just takes money
It's a Fox-4 platform lol!

Yeah Ford counterbalanced it alright....with a huge ass fuel cell hahaha
 

Bill

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Staff member
Donator
True, but the suspension geometry is a bit different as well. The only 00R I've been in was pretty radical, so it isn't really a fair comparison.
 

Bill

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Staff member
Donator
I've never seen a impressive amount of power come out of a cimbo that had shortys of any type.
Agreed, but impressive power (800+) is not likely going to come from a stock longblock Triton. There are exceptions to everything, but impressive power tends to come with impressive investment.
 

na svt

Member
Agreed, but impressive power (800+) is not likely going to come from a stock longblock Triton. There are exceptions to everything, but impressive power tends to come with impressive investment.
To me an impressive amount of power is dictated by the combo, not a given number like 800+. A stock navi engine can make over 400rw, that's impressive while an 11:1 engine with ported heads making just over 400rw is not.

An n/a engine is seriously restricted stock manifolds and shortys. FI combos have it worse and longtubes reduce the cylinder temps greatly which, besides making much more power, also lengthens the life of the engine.

A stock longblock 5.4 4v can add a lotta modrange hp/tq. With the right cams and longtubes one can make over 400rwhp and 400ft lbs, with exh manifolds or shorties it won't happen.
 

Bill

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Staff member
Donator
I mean that you've had some...experiences that most of the other members of this forum probably haven't. And, which one am I in the picture. I look more like the guy on the left, but feel more like the guy on the right. I'm headed to the liquor store in about an hour and will probably be blurry like the ones in the background in about 3 1/2 more hours :D .
 

Svt Fox

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Staff member
I mean that you've had some...experiences that most of the other members of this forum probably haven't. And, which one am I in the picture. I look more like the guy on the left, but feel more like the guy on the right. I'm headed to the liquor store in about an hour and will probably be blurry like the ones in the background in about 3 1/2 more hours :D .
Lol that's fine. For a second I was thinking...

 

Bill

Well-Known Member
Staff member
Donator
Nope. Of all the cars we built over the years, it seems to bet that guy that put $3500 into his fox body that steals the show at the track.
 
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