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5.4L dohc in 86 GT. Which headers??

Hello,
Kinda new to this forum. Ive read this entire thread but i dont see where anyone says exactly where the collision areas are on the longtube header question. Is it the shock towers, steering linkage, brake booster or what? Thanks
 

na svt

Member
Hello,
Kinda new to this forum. Ive read this entire thread but i dont see where anyone says exactly where the collision areas are on the longtube header question. Is it the shock towers, steering linkage, brake booster or what? Thanks
This depends on which headers are trying to be installed.
 
This depends on which headers are trying to be installed.
Dude! LOL! u do realize u answered my "?" with a "?" Im assuming the JBA mid length that was spoken of earlier fit in a Foxbody fine on a 5.4l 4v conversion. But how about a longtube set of JBA's or any brand that you know of.
Thanks
 

na svt

Member
I stated a fact, not a question. Also, JBA doesn't make 4v long tubes and there are no longtubes that will fit with some serious modding. I have some Kooks that come apart like the Bassani mids that would be easier to make fit than headers that are one piece.

The JBA mids may fit but the 1 5/8" versions are too small for a 5.4.
 

Bill

Well-Known Member
Staff member
Donator
We have a JBA factory rep on here. Why don't you PM him and get on the phone. JBA also owns Doug's Headers and Patriot Exhaust (all owned by Pertronix), so he might be able to get some better data for you. I can tell you that the JBA shorts work great with a 4.6, but I have no experience with the 5.4. Check with Jason. Tell him Bill from ACM says hey.
 
I stated a fact, not a question. Also, JBA doesn't make 4v long tubes and there are no longtubes that will fit with some serious modding. I have some Kooks that come apart like the Bassani mids that would be easier to make fit than headers that are one piece.

The JBA mids may fit but the 1 5/8" versions are too small for a 5.4.
Thanks for the insight!!!
 
We have a JBA factory rep on here. Why don't you PM him and get on the phone. JBA also owns Doug's Headers and Patriot Exhaust (all owned by Pertronix), so he might be able to get some better data for you. I can tell you that the JBA shorts work great with a 4.6, but I have no experience with the 5.4. Check with Jason. Tell him Bill from ACM says hey.
Thanks!!! I am in the info gathering stage right now as far as engine choice is concerned. I own an 1984 convertible and I have an IRS out of a 2003 cobra that I'm gonna add so far.
 

Quicksilver

Member
View attachment 747
Please forgive me for my blatant act of plagiarism. I stole this from the Sullivan Performance web site (many moons ago) for personal use.
This is why longtube headers are an issue on the 5.4 conversion. By the time you're down to the ports, the difference is about 1.25 inches, but 5/8" on each side is a lot when it comes to longtube clearances. I have seen several make it work with a rosebud and a pry bar. You have to decide how bad you want LTs.
Do you have a ballpark weight in the 2011 5.4 from a gt500. My understanding is this is the first year of the aluminum block in the gt500.
 
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